Advanced Pwr Elect Interfaces for Distrib Energy
A national laboratory of the U.S. Department of Energy
Office of Energy Efficiency & Renewable Energy
National Renewable Energy Laboratory
Innovation for Our Energy Future
Advanced Power Electronics
Interfaces for Distributed Energy
Workshop Summary
August 24, 2006
Sacramento, California
B. Treanton and J. Palomo
California Energy Commission
B. Kroposki and H. Thomas
National Renewable Energy Laboratory
NREL is operated by Midwest Research Institute ● Battelle
Contract No. DE-AC36-99-GO10337
Workshop Summary
NREL/BK-581-40480
October 2006
Advanced Power Electronics
Interfaces for Distributed Energy
Workshop Summary
August 24, 2006
Sacramento, California
B. Treanton and J. Palomo
California Energy Commission
B. Kroposki and H. Thomas
National Renewable Energy Laboratory
Prepared under Task No. WW88.2005
National Renewable Energy Laboratory
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Operated for the U.S. Department of Energy
Office of Energy Efficiency and Renewable Energy
by Midwest Research Institute • Battelle
Contract No. DE-AC36-99-GO10337
Workshop Summary
NREL/BK-581-40480
October 2006
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Executive Summary
The Advanced Power Electronics Interfaces for Distributed Energy Workshop, sponsored by
the California Energy Commission Public Interest Energy Research (PIER) program and
organized by the National Renewable Energy Laboratory, was held Aug. 24, 2006, in
Sacramento, Calif.
The workshop provided a forum for industry stakeholders to share their knowledge and
experience about technologies, manufacturing approaches, markets, and issues in power
electronics for a range of distributed energy resources. It focused on the development of
advanced power electronic interfaces for distributed energy applications and included
discussions of modular power electronics, component manufacturing, and power
electronic applications.
The workshop was organized into four sessions:
•
•
•
•
Experience With Modular Power Electronics
Advanced Concepts and Components
Modular Power Electronics
Power Electronics for Distributed Energy Applications.
Each session included multiple presentations, and subsequent discussion periods allowed
attendees to ask questions and share thoughts on power electronics issues.
The presentation and discussion sessions revealed several themes:
• The need for a standardized interface for power electronics
• The importance of scalability in power electronics
• The importance of modularity in power electronics
• The need for power electronics to perform with high reliability and mean time
between failure
• The need to reduce the cost of power electronics components and address the
increasing cost of current designs
• The reluctance of industry to forfeit proprietary designs for a standardized interface
and the threat/opportunity of commoditization
• The need for longer warranties for power electronics products
• The need for improved certification scenarios and lower-cost certification methods
• The need to plan for power electronics early in system designs to reduce cost and
increase effectiveness.
• The recognition that power electronics interface manufacturing will compete in a
global market.
iv
The information collected from this workshop is a resource for organizations that plan to
submit proposals in response to an upcoming California Energy Commission PIER request
for proposals for an advanced power electronic interface.
Information about the workshop was posted on the California Energy Commission PIER
Web site (see http://www.energy.ca.gov/pier/notices/2006-0824_workshop_power_elect.html). Forty-one people—representing industry, state and federal
government, and national laboratories—attended.
v
Acronyms
APEI
CBEMA
CPES
DER
EPS
ETO
IEEE
NREL
ONR
PEBB
PIER
PV
R&D
UL
UPS
Advanced Power Electronics Interface
Computer Business Equipment Manufacturers Association
Center for Power Electronics Systems
distributed energy resources
electric power system
emitter turn-off
Institute of Electrical and Electronics Engineers
National Renewable Energy Laboratory
Office of Naval Research
Power Electronics Building Block
Public Interest Energy Research
photovoltaics
research and development
Underwriters Laboratories
uninterruptible power system
vi
Definitions
Distributed energy resources (DER): DER are electric power sources located at or near the
point of use or load center. DER include distributed generation, distributed energy storage,
and demand response efforts. The energy generation resources include a range of
technologies, such as photovoltaics, wind turbines, fuel cells, microturbines, combustion
turbines, reciprocating engines, gas- and steam-powered turbines, Stirling engines, biomass
systems, and solar thermal systems. Related systems and supporting technologies include
integrated storage systems, power electronics, and control technologies.
Plug and play: An approach in which hardware and software work together to automatically
configure devices and assign resources. This allows hardware changes and additions without
large-scale adjustments or modifications. The goal is to be able to plug in a new device and
immediately use it, without complicated or significant setup modifications or adjustments.
STATCOM: An abbreviation for “static compensator.” This device is a shunt-connected
voltage controller typically used to limit reactive power fluctuations or harmonic content. It
does not contain energy storage but can actively inject or draw reactive power.
vii
viii
Table of Contents
1
Introduction .................................................................................................................................. 1
1.1
1.2
2
Workshop Introduction ............................................................................................................... 3
2.1
2.2
2.3
3
3.2
3.3
3.4
4.2
4.3
4.4
“Advanced Topologies for Distributed Energy Interface,” Ned Mohan,
University of Minnesota .................................................................................... 12
“Integrated Modules Simplify Systems Design,” John Mookken,
SEMIKRON Inc................................................................................................. 12
“Distributed Energy Advanced Power Electronic Interfaces,” Ben Kroposki,
National Renewable Energy Laboratory............................................................ 13
Session 2 Discussion.......................................................................................... 15
Session 3: Modular Power Electronics Distributed Energy Applications ........................... 17
5.1
5.2
5.3
5.4
6
“Power Electronic Building Blocks: Office of Naval Research Experience
and Observations,” Terry Ericsen, Office of Naval Research ............................. 6
“Integrated Power Electronics Building Block Modules, Converters,
and Systems,” Fred Wang, Virginia Tech ........................................................... 7
“Bricks and Buses,” Giri Venkataramanan, University of Wisconsin................. 8
Session 1 Discussion............................................................................................ 9
Session 2: Advanced Concepts and Components................................................................. 12
4.1
5
“Power Electronics for Utility Applications at the Department of Energy,”
Imre Gyuk, Department of Energy ...................................................................... 3
“Power Electronics Research Assessment,” Forrest Small, Navigant................. 4
Workshop Introduction Discussion...................................................................... 5
Session 1: Experience With Modular Power Electronics ........................................................ 6
3.1
4
Workshop Sponsor............................................................................................... 1
Workshop Structure ............................................................................................. 2
“Modular and Scalable Power Converters in the Uninterruptible Power
Supply Industry,” Ian Wallace, Eaton................................................................ 17
“Distributed Energy Applications Leverage High-Volume, Modular
Power Converters,” Perry Schugart, American Semiconductor ........................ 18
“Modular Inverters for Distributed Generation,” Matt Zolot, UQM ................. 19
Session 3 Discussion.......................................................................................... 20
Session 4: Power Electronics for Distributed Energy Applications..................................... 21
6.1
6.2
6.3
6.4
6.5
“Power Electronics Conversion for Distributed Energy Applications,”
Alex Levran, Magnetek Inc. .............................................................................. 21
“Xantrex Power Electronics for Renewable Energy System Applications,”
Ray Hudson, Xantrex......................................................................................... 21
“Power Electronics for DER and Renewable Applications,” Jonathan
Lynch, Northern Power Systems ....................................................................... 22
“SMA America: Advanced Power Electronic Interfaces Workshop,” Kent
Sheldon, SMA.................................................................................................... 23
Session 4 Discussion.......................................................................................... 24
ix
7
Conclusions ............................................................................................................................... 26
Appendix A: Agenda .......................................................................................................................... 27
Appendix B. List of Attendees .......................................................................................................... 29
Appendix C. Speaker Biographies.................................................................................................... 33
Appendix D. Workshop Presentations ............................................................................................. 36
Appendix E. Additional Resources................................................................................................. 221
x
1
Introduction
The Advanced Power Electronics Interfaces for Distributed Energy Workshop, sponsored by
the California Energy Commission Public Interest Energy Research (PIER) program and
organized by the National Renewable Energy Laboratory (NREL), was held Aug. 24, 2006,
in Sacramento, California.
The purpose of the workshop was to create a forum for a diverse range of distributed
energy resource (DER) industry stakeholders to learn about experiences and related
technologies and explore the issues and options for DER power electronics. It focused on
the development of advanced power electronic interfaces for distributed energy
applications and included discussions of modular power electronics, component
manufacturing, and power electronic applications.
1.1 Workshop Sponsor
The California Energy Commission, California's energy policy and planning agency,
forecasts energy needs, keeps historical energy data, licenses thermal power plants, promotes
energy efficiency, develops energy technologies and renewable energy, and plans for and
responds to energy emergencies. In 1996, the Electric Utility Industry Restructuring Act of
1996 expanded the commission’s responsibilities by establishing the PIER Program. The act
required that at least $62.5 million be collected each year from investor-owned utility
ratepayers to fund public interest energy research.
The PIER Program partners with individuals, businesses, utilities, and public and private
research institutions to conduct research on promising technologies, products, and services. It
focuses on:
•
•
•
•
•
•
•
Buildings end-use energy efficiency
Energy innovations small grant program
Energy-related environmental research
Energy systems integration
Environmentally preferred advanced generation
Industrial/agricultural/water end-use energy efficiency
Renewable energy technologies.
Power electronics fall within the purview of the PIER Energy Systems Integration group.
This group takes a systems engineering approach to the electricity delivery system and
focuses on transmission research, distribution research, and the integration of DER into the
power system. A significant part of this group’s $42 million research portfolio is committed
to demonstrating the benefits of DER integration for utilities, regulators, and ratepayers.
Power electronics, a key technology in this area, can reduce the costs of interconnection and
improve the integration of DER technologies.
1
Toward this end, PIER has partnered with the NREL to address power electronics issues.
Called the Advanced Power Electronics Interface (APEI) Initiative, this six-year, $20million-plus effort is a coordinated plan to develop a modular architecture for standardized,
highly integrated power electronics interconnection technologies that will come as close as
possible to “plug-and-play” for DER platforms.
The goal of the APEI Initiative is to develop power electronics technology that improves
and accelerates the use of DER systems. The objective is to reduce costs for DER and
interconnections by developing standardized, high-production-volume power
electronic modules.
NREL is the U.S. Department of Energy’s premier research facility for renewable energy and
energy efficiency research. As part of its mission, NREL has established a Distributed
Energy Systems Integration group to facilitate the interconnection of DER with the electric
power system (EPS). The Distributed Energy Systems Integration group focuses on testing
and certification, standards and codes, technology development, DER applications, and
regulatory issues.
1.2 Workshop Structure
The workshop provided a status update on DER power electronics designs, manufacturing
approaches, and issues. PIER will use the information gathered to determine issues its
research could address and strategies for the APEI Initiative. The information will also be
used to develop a future California Energy Commission PIER request for proposals for an
advanced power electronic interface.
The workshop was organized into four sessions:
•
•
•
•
Experience With Modular Power Electronics
Advanced Concepts and Components
Modular Power Electronics
Power Electronics for Distributed Energy Applications.
Sections 3 through 6 provide summaries of the workshop presentations. The full
presentations are included in Appendix D. As an additional resource, a presentation by Dr.
Alfred Engler, Institut für Solare Energieversorgungstechnik, is included in Appendix E.
2
2
Workshop Introduction
Mark Rawson, program lead of the PIER Energy Systems Integration team, opened the
workshop by welcoming participants and providing background information about the
APEI Initiative.
The PIER Energy Systems Integration team uses a systems engineering approach in its work
to integrate energy efficiency, demand response, DER, renewable energy, and energy storage
into the EPS. It focuses on science and technology advancements in sensors and monitoring,
power electronics, communications and controls, intelligent automated systems, and realtime operations.
Two of PIER’s seven strategic objectives are addressed by the advancement of power
electronics:
• Enable optimal integration of renewables, distributed generation, demand response,
and storage to the power system.
• Improve cost and functionality of components to integrate demand response,
distributed generation, and electricity storage into the system.
The APEI Initiative, under the direction of PIER Energy Systems Integration and NREL, will
facilitate the advancement of the power electronics industry by enabling the production of
more cost-effective products.
2.1
“Power Electronics for Utility Applications at the Department of Energy,”
Imre Gyuk, Department of Energy
Power quality is critically important to today’s digital economy. In fact, common nominal
power quality events cost the nation about $52 billion each year. To address power quality
issues, the Energy Storage program within the Department of Energy’s Office of Electricity
Delivery and Energy Reliability has researched a number of advancements in energy storage
technologies and power electronics, including a large-scale uninterrupted power system
(UPS) that could be factory-integrated, tested, and used in plug-and-play installations.
Based on CBEMA curves (which were developed by the Computer and Business Equipment
Manufacturers Association to simplify the modeling of system response and evaluate all
factors in voltage deviations from the norm) from the Electric Power Research Institute,
researchers determined that a system that could provide power for 15–30 seconds would
cover 95% of all outages. A mobile, 2-MW, 15-second battery system was designed to meet
these requirements. This system won an R&D 100 award and is now used throughout the
country. A later generation, which provides 10 MW for 30 seconds, is now in service in a
microchip plant in Arizona. Another, which uses a sodium sulfur battery rather than a lead
acid array, provides peak shaving at a substation.
Other areas of research have included optically isolated inverters; advanced heat exchangers;
low-cost, modular, highly-reliable inverters; emitter turnoff switches; and transmission
stabilization devices.
3
The emitter turn-off (ETO) switch, developed by Virginia Tech and North Carolina State,
was conceived from the need for a faster, more powerful, and cheaper switch. The resulting
product is 15–20 times faster than a gate turnoff thyristor and has three times the power of
the more-expensive insulated gate bipolar transistor. This technology also was awarded an
R&D 100.
The transformerless STATCOM with energy storage was created through a collaboration of
organizations with the goal of providing four quarter control with both real and reactive
power. Although two-thirds of an example trailer-mounted installation employed
supercapacitors, one-third made use of the ETO.
Finally, a more recent project has addressed the power quality issues associated with a 48MW Bonneville Power Administration wind farm. Customer complaints and variable voltage
led the administration to seek solutions. A trailer-mounted ETO STATCOM couple with grid
power was one suggestion. The group is currently pursuing this option.
Projects such as these are showing the potential of power electronics. In fact, a recent
meeting that brought together representatives of the national laboratories, renewable and
electricity research groups, and the Office of Science determined that power electronics and
energy storage should be priority areas for investment.
Future research plans include work with advanced materials, ETO deployment, thermal
management systems, novel materials, silicon carbide switches, high-temperature materials,
ionic fluids for electrolytes, advanced wideband gap system deployment, nano-structured
materials, and diamond switches.
2.2 “Power Electronics Research Assessment,” Forrest Small, Navigant
In 2004, Navigant Consulting Inc. worked with PIER’s Energy Systems Integration team on
research assessment and planning for power electronics. The goal was to identify research
activities the commission could support to increase the penetration of DER in California.
To do so, Navigant first surveyed stakeholders to identify their key business needs. It found
that the expense of power electronics—as much as 40% of DER system cost—has inhibited
the use of DER. It also found that the current performance of power electronics was lacking
and hindering long-term commercial application.
Navigant then analyzed the technology challenges related to these needs. It found:
•
A lack of standardization and inter- and intra-operability of power electronic systems,
components, and the grid
•
A need for power electronic devices that are modular and scalable
•
A need for improvements in power electronic system packages.
4
Navigant next identified 10 potential research initiatives to address the technology
challenges. It ranked the initiatives based on their relative impact to DER systems, their
relevance to the public interest, and the existing gap between current and necessary research.
Based on the rankings, it identified three key initiatives:
• Standardize the interface between power electronics systems and the grid.
• Standardize and improve the interoperability of power electronics components and
systems.
• Improve the scalability/modularity of power electronic systems and components.
Navigant believes these initiatives offer the greatest potential to affect future development
and recommended that the PIER team pursue them with a systems approach. These findings
were the basis for the California Energy Commission to proceed with the APEI Initiative.
2.3
Workshop Introduction Discussion
•
Who manufactures the ETOs in Dr. Gyuk’s projects?
The ETO is not being commercially manufactured. At this time, it is made only at the
university. However, there is some interest, and manufacturers are being pursued.
•
It was mentioned that power electronics correspond to up to 40% of the cost of DER
systems. Does that include motors and generators as part of power electronics?
Navigant performed a round buildup of the cost of a representative DER system to
determine what percentage of the cost would belong to power electronics
components. Forrest Small, of Navigant, believes this counted only inverter and
control systems.
5
3
Session 1: Experience With Modular Power Electronics
3.1
“Power Electronic Building Blocks: Office of Naval Research Experience
and Observations,” Terry Ericsen, Office of Naval Research
In 1994, the Office of Naval Research (ONR) instituted the Power Electronics Building
Blocks (PEBB) program, an effort to develop a universal power processor capable of
changing any electrical power input into any voltage, current, and frequency output. The goal
was to create a product that would enable high-volume production of small power electronics
to reduce their cost and development time. The resulting PEBB is envisioned to be softwarereconfigurable, multi-purpose, “smart,” and universal (i.e., it replaces specialized devices
such as power conditioners, inverters, and circuit breakers). However, numerous advances
are still necessary.
The ONR has identified several challenges to its overall ship design process. These include
rule-based design, standard parts, increasing complexity, specifications and documents, and
small sample statistics.
However, there are other, more general, challenges as well. One example is the role of
simulation. Today, as in the past, simulations are developed as an analysis tool. They are
based on models of a real product to study variations in design. However, simulations can
play a synthesis role in the process. In the future, simulations should be based on
specifications and performed in the early stages of design to determine the final real product.
Another example is the effect of the design cycle—or the lack of one. Because power
electronics do not function in a vacuum, they should be developed in an iterative design cycle
in which requirements influence products and vice versa. It was noted that the use of general
models in the design process is more productive than the use of specific ones because they
help developers avoid overly constrained problems.
Then there is complexity. Complexity is a result of emergence. That is, complex systems
display a behavior that cannot be predicted based on the behaviors of their individual parts.
Complexity is not a product of the number of parts. Complex systems can be simplified
through physics-based partitioning, the addition of intelligent active devices, and the creation
of controlled and predictable system states at physics-based partitions. However, reducing
complexity increases the detail, size, weight, and cost of the power electronics. Therefore,
these traits must be reduced to enable practical application and overall simplification of
complex systems.
Three recent innovations will influence the future development of power electronics: (1)
increased computing power; (2) the development of high-speed, low-cost controllers; and (3)
system-simplifying concepts. These are important innovations that will touch on multiple
aspects of development and enable new advances.
6
An additional problem relates to investor influence. Up to a point, if money is invested into a
development process, the final cost of the product will decrease and performance will
improve. Obviously, at some point, more money must be invested to extract diminishing
performance returns. Between these is an optimal point, at which the balance between
investment and performance is ideal. For investors, their influence is very high early in the
development process, when their investments garner big returns on performance. But as
progress is made, changes become more difficult, and investor influence weakens. Therefore,
for effective development and maximum influence, investors must become involved early in
the process, and developers must employ modeling and simulation to guide the process.
All of these issues have influenced the vision and development of PEBBs. Other important
influences include the concepts of partitioning, concurrent engineering, early validation, and
universal, or “plug and play” components.
Today, a working group headed by Narain Hingorani is developing an IEEE standard using
the PEBB concept for electrical power systems. There are also some examples of PEBBs
already in use. Three to five megawatts have been installed for a variety of applications.
Finally, future needs also include modeling standards, benchmark models, a library of
models, and a body of international volunteer experts for these efforts.
3.2
“Integrated Power Electronics Building Block Modules, Converters, and
Systems,” Fred Wang, Virginia Tech
The Center for Power Electronics Systems (CPES), a National Science Foundation
engineering research center, is focused on the development of integrated power electronics
modules. Its vision is to follow the example of micro-electronics by achieving integrated
functionality, a standardized interface, and a versatile product suitable for mass production.
Power electronics interfaces are a key enabling technology for DER. They offer the potential
of lower costs, higher reliability, and improved performance. To achieve this, other
organizations are pursuing the conventional approach of improving the components, devices,
and circuits of power electronics. CPES, however, has adopted an alternative approach of
modularization, standardization, and integration to achieve economies of scale. It also
emphasizes a system perspective in its work.
CPES’ specific approaches include integrated load converters (including motor-converter
integration and microprocessor-converter integration), power distribution converters, and
integrated source converters. For each, CPES begins with basic research on the devices,
materials, and technology and then moves to developing enabling technologies and, finally,
engineered systems. Already, through research funded by ONR’s PEBB program and other
sponsors, CPES has developed numerous integrated power electronics modules ranging from
10 W to 10 MW. CPES researchers are now addressing the issues of a building block
approach, architecture and partitioning, and interface characterization.
CPES starts at the bottom with a topology and builds from that foundation up to application
layer control in a hierarchical structure. This requires the correct control architecture and
communication protocols.
7
Finally, CPES has realized additional benefits to integrated power converter functionality.
These include power flow control; power management; power quality control; monitoring,
diagnosis, and online mitigation; and protection.
3.3 “Bricks and Buses,” Giri Venkataramanan, University of Wisconsin
The largest markets for power electronics today are in relatively large-volume areas such as
motor drives, power supplies, UPSs, and compact fluorescents. However, these are
segmented markets, and it is unclear if DER can establish itself as a new market segment.
To create a new market segment, DER power electronics must overcome challenges. For
example, a typical inverter is a complicated piece of equipment. The power electronic, filter,
transformer, and controller components form a jungle of wires and electronics. Because of
this, power electronics applications are assembled by hand—even in mass production
scenarios. This production process is expensive and inhibits cost reductions. If significant
cost reductions are to be realized, automated assembly, fabrication, and compilation are
necessary. Other constraints include low reliability, custom designs, and long design cycles.
Therefore, the future of power electronics must include standardized input, output, and
functionality; “compilable” cabinets; and fail-safe and plug-and-play capabilities as well as
units compatible with multiple geometries.
Modular systems are in production. Eaton has developed a molded case circuit breaker board
into which input and output breakers, transient voltage surge suppressor modules, and card
and voltage sensors can be plugged. Therefore, minimum assembly is involved. Rockwell
has introduced a product line of several drives that are pre-engineered to work together.
These incorporate control and communication cables interfaced through a bus and a line
interface module that is pre-engineered for ease of integration. These are models for DER
market development.
8
Several years ago, with support from the California Energy Commission and other sources,
the University of Wisconsin – Madison began to develop a “bricks and buses” converter.
This work involved demonstrating a concept prototype with electrical performance
comparable to that of classically designed products, increased power density, modular
packaging, and improved manufacturability.
One result of this work was a 3.2-kW, single-phase inverter. The inverter integrates the
switch gear, rectifier module, capacitor, inductor, and output. On the bottom, mechanical,
power, and control buses are positioned for “brick” interconnection. Each of its modules is
independently thermally managed. However, other models are also possible.
The “bricks and buses” example offers standard depth and height dimensions but
varied widths. In addition, it has variable volume, proportional scaling of the
surface area, a decoupled power bus and signal bus, and a contained interconnect
electromagnetic interference.
However, there are still challenges. The cost, size, and lack of modularity of the many
components are major barriers. For example, the prices of copper and steel, which are used
for the magnetic elements, have increased substantially over the past 5 years. Many of these
components can be produced with less expensive materials and in more modular structures.
Such advances could make possible alternatives. An example is a system that could include a
switch, throw capacitance, pole magnetics, and thermal management. These cells can be
combined to increase power rating and number of phases. Other advanced concepts include
air- and liquid-cooled designs and bus-centered assemblies.
3.4
Session 1 Discussion
•
The initial PEBB program focused on Navy ship power systems. For that program,
how many eventual manufacturers are there? And are their products compatible with
one another’s, or are they just compatible within each company?
The Navy is not a mass buyer, and it does not buy these types of systems frequently. So
it is not an industry. To create an industry and bring down costs for the Navy, utilities
and others must be involved. ONR has employed a spin-on/spin-off strategy to spin off
its investments to companies such as ABB and Rockwell. So far, several PEBBs—
including one aboard a GLIB, or Great Lakes Icebreaker—have been put into use
through this arrangement.
Manufacturers have an incentive to adopt the PEBB process because of economies of
up to five- to ten-time reductions in engineering costs. ONR’s next development will be
plug-and-play units. At that point, it is expected that costs will start to be driven from
the customer side. The question remains of how to provide incentives for this step.
9
•
How realistic is it that PEBBs can accommodate distributed generation and storage
in increasingly large power classes? More specifically, is the PEBB approach one
that focuses within classes, or can it be used to cross classes of power
electronics packages?
The idea is to do both. In fact, as the various markets and industries progress, they are
becoming more similar. For example, they are losing fuses and breakers as solid state
becomes more common. The ABB SCS 5000, a medium-voltage system for ship
drives, is a 20-MW system with no fuses or breakers.
However, this may be a challenge for utilities that want to visually check switch gear
and relays. In the ship system, this is not an issue because there are no uncontrolled
generation sources and so no reason to employ fuses and breakers to protect the
system from such threats.
•
The business paradigm also must change, and it is. In the past, the manufacturers
have associated themselves with a particular application segment (e.g., drives or
wind generation). But with converter modules or PEBBs, they must associate with a
line based on power level rather than application.
Eventually, this will mean original equipment manufacturers will be able to offer
application solutions within short time frames, much like the computer industry. This
is a difficult move for industry, but it is beginning to happen.
•
If there is a failure in a module, is there some type of diagnostic to identify which
module needs attention? Can that module be replaced, or must the entire block
be discarded?
At this point, this is not possible. However, it is the intent for the future. Upon failure,
the module would shut itself off and electrically isolate itself from the other units. The
long-term goal is modules that are “hot swappable,” meaning that they can be replaced
without shutting the system down.
This type of functionality will require a definition of an architecture, and the
IEEE working group is working on one now. Another idea for such functionality
uses “agents” located inside each PEBB. When the system is activated, the agents
would communicate with one another to determine the incorporated functions and
operate appropriately. This could lead to the development of dynamically
reconfigurable systems.
10
•
What are the biggest barriers to industry adoption of a bricks and buses approach?
In approximately 2003, Dr. Venkataramanan held a workshop of power electronics
industry representatives in Madison, Wisconsin. The feedback he received revealed
hesitations to dismantle practices and systems designed for established industries
(e.g., power supplies or motor drives).
However, there has been change since that time, and some of the new thinking is
being incorporated into new designs. Further, this workshop is focused on power
electronics for DER, which is a new industry. It will likely be easier to work with all
the players early on, before they are entrenched in practices and systems.
11
4
Session 2: Advanced Concepts and Components
4.1
“Advanced Topologies for Distributed Energy Interface,” Ned Mohan,
University of Minnesota
The University of Minnesota has performed power electronics research at the detailed level
of topologies. This work has included an ultra-compact, high-efficiency, hybrid converter for
photovoltaics (PV) and fuel cells and a multi-port DC-DC converter. The multi-port DC-DC
converter is a compact unit that works as an interface between two or more energy sources
and a load. It allows power flow from different energy sources to a load and bidirectional
flow for all sources (e.g., for a battery). The converter is intended for use in hybrid vehicles
and residential homes/buildings.
More recently, the university has been working to simplify the control of matrix converters to
control motors and generators. It has found that silicon carbide-based converters, which can
operate at very high temperatures, are particularly promising.
The voltage-link power electronic system is common, but there are problems with its storage
capacitor—and particularly with weight, cost, and reliability. In addition, the capacitor has
problems with in-rush current, and it is difficult to integrate with motors.
Matrix converters, however, have no energy storage element. They operate AC-AC and offer
bidirectional power flow. The university used ideal transformers to simplify how switching
signals are generated and therefore simplify matrix converter control.
The university’s study then pushed the technology by incorporating an AC machine to
improve its performance. It found it could almost double it. By taking an AC machine’s
Wye-connection and opening it up and feeding it from matrix converters from both sides, it
found it could eliminate bearing currents, deal with isolated voltages, reduce slab insulation,
control input power factor, and increase power capability. In addition, because the converters
take advantage of the new silicon carbide materials, they have the potential for reduced costs
because they do not require expensive copper and steel. And finally, functionally, they are
PEBBs. They eliminate the need for bulky storage capacitors.
Future research on matrix converters will analyze the efficiency of the system, explore how
to make the current ripple smaller, and determine ways to operate at lower frequencies.
4.2
“Integrated Modules Simplify Systems Design,” John Mookken,
SEMIKRON Inc.
Power modules have evolved significantly since their introduction in the 1960s. Each
generation has introduced improved power densities and new components, and each
generation has evolved to integrate more components into the modules. Today, power
modules integrate diodes, switching devices, gate drives, current sensors, voltage sensors,
and temperature sensors.
12
The trend toward integration has several drivers, including a shorter time to market, easier
system design and assembly, improved economics, and a reduced number of components. In
addition, integration offers benefits such as customized solutions for regular prices, standard
interfaces, and standard platforms.
At SEMIKRON, the latest design is the SKAI, which also includes the digital signal
processor controller, a move toward intelligence in the module. (However, the module is
not yet fully “intelligent” because the software is not included.) This programmable module
was developed with U.S. Department of Energy funding over a 3-year period that began in
1999. It is an advanced design that begins to blur the boundary between power modules
and motor drives.
The SKAI consists of a core platform (which consists of the semiconductors and capacitor) and
customizable components (i.e., the insulated gate bipolar transistors, digital signal processor,
controller, power supply, gate driver, protection, and heat sink). SEMIKRON designed the
module to work with various applications but incorporated flexibility into the design based on
its customer experience. It found that its customers liked the product, but, because of its
general design, it was not optimized for their needs. The customizable components offer them
the flexibility to build an optimized solution while taking advantage of the benefits of
standardization. Today, only about 5% of SKAI sales are for unmodified units.
The SKAI can be configured using 600 V or 1,200 V insulated gate bipolar transistors with
continuous AC output currents of 400 A rms or 300 A rms, respectfully. The module
includes either a liquid-cooled or air-cooled heat sink. It is about the size of shoebox and can
be manufactured in large quantities. All customizations are additions to the manufactured
unit, so they do not affect manufacturing costs. The SKAI can be used for a variety of
applications, depending on the customer’s need and software.
SEMIKRON has experienced varying reactions to the standardized platform. It has generally
found that its customers like the standardization concept—for their own product ranges. But
most do not want outside products to be able to plug into their architecture. However, this is
the general growth pattern in the industry and is likely to be overcome. For example, earlier
power module designs from one company were eventually adopted by others so they could
serve the replacement market. Customers especially like this situation because it results in
competition. However, it makes the product a commodity, and power module manufacturers
have incentives to resist this situation.
4.3
“Distributed Energy Advanced Power Electronic Interfaces,” Ben
Kroposki, National Renewable Energy Laboratory
Distributed energy applications include wind turbines, PV arrays, fuel cells, microturbines,
and reciprocating engines. Although they are not new technologies, they are receiving
increased attention today because of their ability to provide combined heat power, peak
power and demand reduction, backup power, improved power quality, and ancillary services
to the power grid.
13
One concern with distributed energy applications is their interconnection with the grid.
Interconnection technologies have the potential to simplify this issue by performing the
integration for all DC generation technologies as well as for generators. However, in addition
to the basic integration, they can provide broader functions. Many small distributed energy
systems already incorporate these functionalities in their inverter technology. Larger systems,
however, generally incorporate these functions through separate pieces of equipment.
Power electronics have the potential to improve the interconnection of distributed energy
applications and the power grid. In one scenario, they are used as an interface between the
DER unit and the grid. In another, they are used to facilitate the creation of “islands” or
“microgrids” by replacing circuit breakers.
Such applications can have many benefits. For example, the use of power electronics to
interconnect DER can improve operating efficiencies, improve power quality, provide Var
support and voltage regulation, reduce distributed energy fault currents, allow
interoperability of multiple sources, and provide for standardization and modularity.
Key to the interconnection of distributed energy applications are the ongoing efforts of the
IEEE 1547 working groups. These groups are developing a series of standards to address the
technical requirements interconnection. IEEE 1547 Standard for Interconnecting Distributed
Resources With Electric Power Systems, the first of the series, was approved in 2003, and
1547.1 Standard for Conformance Test Procedures for Equipment Interconnecting
Distributed Resources With Electric Power Systems was approved in 2005. These standards
provide a foundation for efforts to develop power electronics-based interconnection
equipment. Five more standards in the series are under development and will provide more
guidance. In the future, a possible standard may address power electronics interface
specifications. NREL, through support from the Department of Energy Office of Energy
Research, is leading these efforts.
Further, the tests outlined in IEEE 1547.1 to ensure proper interconnection have been
incorporated into Underwriters Laboratories (UL) 1741 Inverters, Converters, Controllers, and
Interconnection System Equipment for Use With Distributed Energy Resources. This provides
manufacturers of power electronics or other interconnection equipment with a consistent set of
testing requirements for their products. UL 1741 was updated to include these requirements
last November, and manufacturers have 18 months from that date to comply.
NREL also performs testing and evaluation of DER systems and components at it Distributed
Energy Resources Test Facility in Golden, Colo. This facility will be used for testing and
evaluation of equipment developed as a result of the upcoming PIER Advanced Power
Electronics Initiative solicitation.
14
4.4
Session 2 Discussion
•
Presentations in the first session focused on the different functional modules in the
PEBB concept and their standardization, but John Mookken focused on standardizing
only the power module. What cost savings can be realized from standardizing only
that piece?
The standard power module includes the driver and controller, but both can be
replaced, if the customer desires. The biggest cost contributors are the capacitor, the
current sensor, and the silicon.
•
Five percent of SEMIKRON’s orders for the SKAI were for off-the-shelf units. What is
the cost increase for changes to those units?
Because no manufacturing modifications are necessary to accommodate the changes,
the cost on a per-unit basis is virtually insignificant. The only changes that
significantly affect cost are adding more capacitance into the module or scaling up the
power level.
•
Does the SKAI come with a warranty, and if so, do customizations affect the warranty?
SEMIKRON offers a 2-year warranty for the SKAI. Customized models are
also covered.
•
First, manufacturers have until May 2007 to comply with the requirements of 1547.1
and UL 1741, and UL is not yet prepared to certify to 1547. However, utilities are
beginning to require 1547.1 certification. This is, in effect, locking the manufacturers
out of some utility districts. Second, 1547.1 introduced new requirements that resulted
in manufacturers having to redesign and recertify their equipment. This is a very
expensive process. Will the other standards in the 1547 series have similar effects?
IEEE 1547 and IEEE 1547.1 are actual standards, but the rest of the series consists of
guides and recommended practices. Therefore, few or no requirements should be
developed as part of their introduction (with the possible exception P1547.6 and
operation on distribution secondary networks). Unfortunately, for the 1547 and
1547.1 requirements, meeting them is a cost of doing business in the DER market.
UL1741 provides a way to certify products to those standards.
•
There has been a lot of discussion of standards. Are the future PEBB standards for
consumers or application suppliers?
The consumer likely has the most to gain from a standard. As mentioned earlier, this
would eventually result in a commodity product and lower prices. This is why some
manufacturers resist the concept of standards.
15
•
There is resistance to standardization, but there are benefits also. The market
increases with commoditization because of lower costs and standardization.
However, it can also work the other way. Consumers want the lowest possible price.
In some instances, they may want a custom solution (e.g., they do not need a standard
part) to further lower costs.
•
Have the matrix converters discussed by Dr. Mohan been tested to confirm the
doubling of power?
Not yet. The idea is only in the conceptual and analytical stages at this point.
•
Is the NREL test facility able to implement and test microgrid configurations?
The facility is flexible and includes a variety of distributed generation sources. It can
be used for low-voltage configurations of less than 600 V. Additional equipment
would be necessary for medium-voltage configurations.
•
Are their problems with the 60-Hz harmonics in the matrix converter because there
aren’t any passives?
No. Matrix converters can synthesize any frequency desired at the output. In the past, a
drawback was that the output voltage was only 86% of the input voltage. The new
configuration achieves 186%. It also allows control of the input power factor. However,
this is all analytical at this time. It has only been simulated through software.
•
One problem with matrix converters is their lack of fault tolerance. How will this be
addressed for interconnection applications?
There must be protection against spikes, but matrix converters are in some ways more
benign than others.
•
What is the IEEE standard for microgrids and intentional islanding?
IEEE P1547.4 Guide for Design, Operation, and Integration of Distributed
Resource Island Systems With EPS is currently under development. It is not a full
standard but rather a guide of how to intentionally island parts of the power system
correctly and safely.
16
5
Session 3: Modular Power Electronics Distributed Energy
Applications
5.1
“Modular and Scalable Power Converters in the Uninterruptible Power
Supply Industry,” Ian Wallace, Eaton
Sensitive (e.g., data centers, servers, and clinical laboratory equipment) and critical (e.g.,
broadcast transmitters, industrial process, and government facilities) power applications
require high quality. Even brief interruptions in power supply or quality can severely affect
function and profits.
The EPS typically provides 99.9%, or three “nines,” reliability to its users, which is
equivalent to roughly 9 hours of outage per year. However, for mission-critical applications,
this is often not sufficient. These applications require “high nines” reliability, or reliability on
the order of 99.9999% or more.
To achieve “high nine” reliability, most of these systems rely on two elements. The first is
multi-source power, or the use of some combination of utility power, generators, batteries,
flywheels, ultracapacitors, etc. The second is a UPS, located between the power sources and
the load. In the event of a power quality or availability problem, the UPS switches the load’s
source to avoid a power outage or equipment damage.
To be effective, UPSs must employ parallel redundancy to ensure availability and avoid
single-point failures. They must be easily expanded to accommodate increased capacity and
growth, and they must have a low mean time for repairs.
Today, the UPS market is growing. It is projected the industry will achieve 10% growth in
revenue per year and a 4% reduction in UPS price. In the market, the drivers for UPS
technology and market growth include:
•
•
•
•
•
•
•
•
Low installation cost
Low operating cost
High power quality utility interface
High power density
Serviceability
Multi-source compatibility
Monitoring, diagnostics, and prognostics
Maintenance services.
Past UPSs were positioned to meet these needs, but they faced two technical hurdles: the
control of two or more paralleled AC power sources and the elimination of all systems-level
single points of failure. These systems were limited to six “nines” or less.
17
Today, Eaton uses Hot Sync technology, a communicationless parallel system, to achieve
seven “nines.” The elimination of communications enables the use of multiple units
connected together and eliminates single points of failure. The identical modules operate
together as peers to share and balance the power. This modular system provides flexibility
and scalability to Eaton’s UPS systems.
Based on this technology, Eaton has developed product lines that can be expanded
incrementally for capacity, redundancy, and volume. In one approach, the control contains
overhead to accommodate the incorporation of future modules, and the modules are
standardized “bricks.” In another, full modular products are hot-swapped on a standard rack.
5.2
“Distributed Energy Applications Leverage High-Volume, Modular Power
Converters,” Perry Schugart, American Semiconductor
Regardless of the size of the system, power electronics are often the last component to be
designed. Frequently, the power electronics designers are forced to accommodate the rest of
the system by squeezing their product into whatever space is left. Often, however, there are
significant benefits to planning for the power electronics early in the design process.
American Superconductor has developed a PEBB with support from the ONR. The PM1000
is a programmable building block power converter designed for high-volume production and
rapid development. Each module is fully contained with controls and power supplies. The
PM1000 uses a power pole architecture and can be air- or liquid-cooled. It is designed to
accommodate customer special needs without converter board modifications. The PM1000
offers two digital signal processors and four operating programs as well as a configurable
graphical user interface.
The modularity of the PM1000 allows rapid development of power converters and power
conversion systems. In addition, its standard power pole enables high-volume production,
low cost, and increased reliability. The use of the PM1000 allows developers to avoid the
time and cost of design, development, iteration, integration, and production. American
Superconductor estimates this saves developers 1 year of development time and
approximately $2 million.
Another product offered by American Superconductor is a developer kit, which includes a
PM1000, a converter interface, a graphical user interface, a software package, and fiber optic
cable with a connector. The software can be changed out to change functionality. For
example, a unit may first be used as an active rectifier but later switched to a DC-DC
converter. No hardware changes are required.
These developer kits cut time to operation even more. For example, a fuel cell manufacturer
bought two of these kits to demonstrate a new concept for providing power to the grid. The
demonstration was operational in less than a week.
18
A related development kit is designed for multiple-converter systems and can use any
converter type (e.g., three-pole or six-pole). This system also allows the use of proprietary
control algorithms. This kit is particularly applicable to DER applications. American
Superconductor also offers the PM2000, a higher-power version of the PM1000.
5.3 “Modular Inverters for Distributed Generation,” Matt Zolot, UQM
UQM’s focus is on high-performance, power-dense, energy-efficient motors and power
electronics for vehicle electrification. Over the past few years, interest has increased in the
potential to connect hybrid vehicles to the power grid. These vehicles could conceivably
provide peak-shaving power or other grid support and charge themselves from grid power to
achieve true electric hybrid status.
However, the automotive industry has different requirements for DG converters if they are to
be packaged within vehicles. To be successful, the converters would need to be high-voltage,
high-density, lightweight, rugged, and low-cost.
UQM’s general specifications for a grid-connect inverter include an input voltage of 150–
360 V, a power output of up to 5 kW, 90% or more efficiency, galvanic isolation, and a
grid and standalone operation of 50/60 Hz. In addition, the unit must meet appropriate UL
and IEEE standards.
UQM uses a Mathworks autocoding setup that takes advantage of existing in-house
capabilities to simplify the control design process. This approach also allows researchers to
perform simulations to test the code before it is downloaded to hardware. This setup will be
used for the DER work to allow for advanced signal processing, true sine wave generation,
and various phase operations.
After analyzing the trade-offs between the performance, cost, and packaging of higherintegration modules and discrete component and the benefits of component-, board-, and
package-level modularity, UQM chose to pursue smaller modular products.
The UQM modular inverter allows incremental additions of 1.7 kW to a 1.7-kW base, up to 5
kW. There is also a package design in which the modularity comes from components added
to a board. A DC front end provides 5 kW and interfaces with the inverters. The whole
system can then be duplicated and multiple systems coupled together. The output voltage can
be configured in various ways.
The goal of a modular system is to prevent redesign to enable high-volume production and
reduce costs. However, to reach this goal, some challenges must be overcome. One challenge
is the actual interconnection. To be truly useful, it must be simple enough for non-specialists
to accomplish. Another involves communication between modules and packages. IEEE
standards do not currently address this, so there is no standard for communication between
different products. Another challenge is anti-islanding. Although it is not a challenge for the
DER industry, it is a new concept for the automotive industry and must be considered.
Finally, there must be a market. At this point, it is unclear if or how the market for such
applications may develop.
19
5.4
Session 3 Discussion
•
Why are the automotive units only 5 kW?
For light-duty vehicles, this is about right. Traction and heavier-duty uses would
require more.
•
Approximately what volumes of the PM1000 are being produced?
American Superconductor is producing hundreds of the converter per year.
•
What sort of list price, in dollars per watt, does the PM1000 have? And what is
smallest power increment?
Currently, there is essentially one power size. The three-phase unit is 175 kilowatts.
The six-pole is about twice that.
The developer kit, which is for three-pole configuration, is just less than $20,000.
However, a volume purchase of the three-pole converter would garner a lower price
per unit. The developer kit is intended for small volumes. Overall, however, the
biggest cost savings come from the avoidance of development costs.
•
Do these products have warranties, and if so, what is the length?
The Eaton UPS products carry warranties of 1–2 years. The American
Superconductor products come with base warranties of 1 year and offer the option of
an extended warranty. The UQM product is still under development.
•
It seems 1–5 years seem to be the lifespan of warranties. What components are
failing?
Electrolytic capacitors and fans often have the shortest lifetimes, but warranties are
not necessarily indicative of lifespan. In addition, service contracts are an important
offering to extend performance.
Another consideration is the trade-off between lifespan and cost. Longer life spans
will require increased costs. There is a balance that must be determined.
20
6
Session 4: Power Electronics for Distributed Energy
Applications
6.1
“Power Electronics Conversion for Distributed Energy Applications,”
Alex Levran, Magnetek Inc.
Magnetek is a power electronics company that develops products for various applications,
including DER. Its DER products serve wind turbines, PV arrays, energy storage, fuel cells,
variable speed generation, and microturbines. Magnetek serves both residential and
commercial markets.
DER applications have specific requirements that must be considered in the design of power
electronics. For example, they must meet grid connection and anti-islanding standards and
technical requirements. They must achieve high efficiencies in both power conversion and
energy harvesting, and they must have compact designs. In addition, power electronics for
DER must be reliable and cost-competitive, and they must be capable of communications and
remote monitoring.
Magnetek’s strategy is to lead the power electronic interface market for alternative
energy systems. Its approach employs a common platform and building blocks into a
scalable, modular, compact design that can be used for multiple DER sources. It uses
high-efficiency, reliable converters; primary energy source control; high power densities;
and system-level control.
Magnetek anticipates several trends in the future of DER technologies. For inverters, new
topologies and improved control algorithms will improve performance. Improvements will
also be realized in thermal management devices, driver and sensing circuits, and capacitors
and magnetic devices. In addition, silicon will be used for more components, and medium
voltage will become more common. Magnetek also predicts the expansion of modular
designs and more flexibility, scalability, and cross-technology platforms.
6.2
“Xantrex Power Electronics for Renewable Energy System Applications,”
Ray Hudson, Xantrex
Xantrex is a power electronics company that is focused on the renewable power, portable and
mobile power, and programmable power markets. It offers products for the solar, wind, and
backup power areas of DER.
For solar, the function of the power electronics is to convert the DC source power to AC
power for use by loads or the electricity grid. The solar grid-tied inverters do not include
backup power capability; they only allow the provision of PV power to the electricity grid.
Off-grid inverters, in contrast, can provide backup power or primary power in locations
without access to the grid. Xantrex offers battery-based, single-phase grid-tied, and threephase grid tied inverter lines. It also offers a charge controller product.
21
These inverters are crucial elements of solar array systems. They provide the user interface
and key safety features. However, they are also very complicated and are often perceived as a
weak link in the overall system because of past reliability issues. For example, solar array
panels come with 20–30 year warranties; inverters come with 5–10 years.
Xantrex’s key requirements for solar application inverters include high efficiency,
advanced communication capabilities, low weight and part count, a sealed design, and
standards compliancy.
For wind applications, the role of power electronics is to convert the variable frequency and
voltage AC power from the turbine(s) into grid-compatible AC power. Unlike PV systems,
wind-based generation must meet Federal Energy Regulatory Commission ride-through
requirements. Xantrex offers products for both the commercial and residential scales.
In addition, Xantrex has developed power electronics for other DER technologies, including
fuel cells, microturbines, advanced energy storage systems, and hybrid systems. However,
this work has been relatively small-volume.
In the future, Xantrex forecasts that power electronics manufacturers will move toward
optimal system design that includes the balance-of-system components. The market will also
see improved performance, with higher reliability, higher efficiency, longer life spans, lower
costs, and simplified installation. For DER, Xantrex anticipates higher penetration levels on
the EPS and a merger between the conflicting requirements for grid-tied wind turbine and PV
applications. It also projects a “feed in” tariff incentive to reward the delivery of electricity
and encourage the optimization of all DER system components.
6.3
“Power Electronics for DER and Renewable Applications,” Jonathan
Lynch, Northern Power Systems
Northern Power Systems works on systems integration and engineering procurement, but it is
steadily expanding its products and services, including those for renewable DER applications.
Through market observation and experience gained from its own installations, Northern
recognized a need for power electronics. It also recognized that power electronics were often
the last part of the system to be considered and that this hindered performance. It saw
opportunities for advanced power electronics to enable simpler interconnections, advanced
power system architectures, utility distribution system support, increased DER ancillary
support, and increased DER penetration.
Based on these observations, Northern determined its power electronics focus. The company
works primarily on applications of 500 kW or more and uses its PowerRouter control system
to enable advanced power system architectures. It is also developing a line of products to
support these systems.
22
Northern’s FlexPhase power converter platform is a modular converter system that
accommodates applications from 500 kW to multiple megawatts. It is available in 480 V and
690 V and contains configurable, rack-in power modules. The modules can be quickly
replaced, and they contain intelligence. A system controller provides overall coordination.
The benefits of the FlexPhase platform include its modularity, performance, size, and cost.
The modular design of the system enables a low mean time to repair, which is particularly
important in remote applications. It also allows serial production, which decreases
manufacturing costs, and standard sizing.
Northern is now using power electronics with conventional DER to standardize the grid
interface, eliminate fault current contributions, add variable speed capability, and enable
advanced architectures. Other recent efforts include the Power Distributor, which uses a
power converter to provide distributed generation to multiple services; a DER utility
interface switch, and the SmartView DER management system.
6.4
“SMA America: Advanced Power Electronic Interfaces Workshop,” Kent
Sheldon, SMA
SMA America focuses on solar technology but also has product areas in communications
and control, railway technology, and advanced energy systems. Within the solar division,
about 80%–85% percent of SMA’s business is for grid-tied units. SMA’s product line
includes residential PV, small wind, and hydro; commercial PV; and backup power and
off-grid inverters.
SMA believes that inverters are becoming a commodity, much like solar panels have.
Maximum achievable efficiencies of 97%–98% are being reached, so cost is the only area for
development and improvement. However, products can be differentiated based on strengths.
At SMA, the strength is communications and control.
SMA offers a Web box communication hub and system logger. This product logs every
inverter on a system and stores the information in data files for customer use. This
technology will be especially useful as renewable energy credit trading becomes more
common, and it enables services such as performance analysis and system alarms.
Another SMA differentiation is its use of AC coupling. In the United States, most off-grid
and backup power systems are connected through battery storage. In AC coupling, SMA
connects the system through an inverter that controls power quality to the load. This design
provides an adaptable system and achieves 96% efficiency to loads.
Recent innovations in SMA power electronics include optic-cooled forced air cooling, an
integrated aluminum enclosure and heat sink, Ethernet communication, and a load-break
rated DC fused disconnect. SMA has also introduced a transformerless, 8-kW grid-tied PV
inverter in Europe that has achieved 98% peak efficiency. Future products include a power
balancer to correct imbalance of multiple inverters on three-phase systems.
23
SMA identified several challenges in today’s power electronics market. These include
pressure to further reduce prices, high competition, high certification costs, and increasing
material costs. However, it also sees promising developments for the future. For future
success, SMA believes there must be a shift to performance-based incentives, an
acceptance of transformerless inverter technologies, and easing of regulatory and
certification requirements.
6.5
Session 4 Discussion
•
Are the megawatt-scale inverters for the large wind projects UL-listed? Do they
conform to UL 1741, or are there other requirements that they must meet?
They do not go through UL, and there is not a specific standard for them other than
safety requirements. Generally, at these sizes, the turbines are “behind the fence” of
the utility and are not subject to UL authority.
•
What is the longest warranty offered on the DER-type inverters?
The standard warranty is 5 years, although some companies also offer extended
warranties for a fee. The 5-year standard was influenced by California Energy
Commission requirements.
•
There was a reference to ride-through in wind installations versus anti-islanding in
PV installations. Is the PV is on the distribution system and the wind on the
transmission system?
Yes, that is a difference. Because these systems interconnect at different levels of the
EPS, they may have different interconnection rules.
•
Is there any standard to qualify digital signal processor software?
Yes, UL 1998.
For a utility application, is there any standard requirement for validation of
the code?
No attendees were aware of any such requirements.
Are there standards for electromagnetic compatibility of internal components of
digital signal processor chips or power electronics?
There are no standards, but there are techniques that can be used to check for this.
24
•
Where do you think price points can be on megawatts-size power electronics if you
produce 100 MW per year?
Price points are variable and depend on the product and its specifications.
•
Have the inverter companies considered their future business plans? Perhaps the
commoditization of inverters will not be a bad thing if it is approached correctly.
Not everyone agrees that inverters will become a commodity. However, much of the
future will depend on the degree that the industry moves to vertical integration, the
level of competition and the number of competitors, and the variations allowed in the
products while meeting standards requirements.
It is difficult for companies in this industry to create long-range plans because the
market environment is very fluid. The regulatory climate and incentives change
frequently, and so do material prices. One option to avoid all of these challenges may
be pre-competitive cooperation, but this is not the way the industry is currently headed.
•
What could increase the reliability of your product lines?
Several things could and do help, including improvements in installation and installer
knowledge, inverter technology maturation, the use of proven reliability techniques,
improved simulation, and service contracts.
•
Other than cost, is there anything about the semiconductors that limit inverter
performance?
Yes, the actual losses in the power electronics. They can be about 3%–4%.
•
Can inverters be designed in such a way that testing costs can be reduced?
The UL requirements are not yet known, and how the tests will be performed is not
know. Easier test points can be added, but the standards must be known first.
In addition, IEEE 1547.1 addresses testing of the black box, the whole package. Even
if individual components of the unit have passed testing individually, it requires that
they be tested again as part of the full system.
25
7
Conclusions
The Advanced Power Electronics Interfaces for Distributed Energy Workshop was organized
to gather information about the status of power electronics technologies. Through workshop
presentations and discussion, several important themes emerged. These included:
• The need for a standardized interface for power electronics
• The importance of scalability in power electronics
• The importance of modularity in power electronics
• The need for power electronics to perform with high reliability and mean time
between failure
• The need to reduce the cost of power electronics components and address the
increasing cost of current materials
• The reluctance of industry to forfeit proprietary designs for a standardized interface
and the threat/opportunity of commoditization
• The need for longer warranties for power electronics products
• The need for improved certification scenarios and lower-cost certification methods
• The need to plan for power electronics early in the system design processes to reduce
cost and increase effectiveness
• The recognition that power electronics interface manufacturing will compete in a
global market.
PIER will use the information gathered to determine issues its research could address and
strategies for the APEI Initiative. The information will also be used to develop a future
California Energy Commission PIER request for proposals for an advanced power
electronic interface.
26
Appendix A: Agenda
27
Agenda
Advanced Power Electronics Interfaces for DE Workshop
Thursday, August 24, 2006
Sponsor: California Energy Commission
Location: 1516 9th Street Sacramento, CA
A WORKSHOP TO FOCUS ON THE STATUS OF DEVELOPMENT OF ADVANCED POWER ELECTRONIC INTERFACES FOR
DISTRIBUTED ENERGY APPLICATIONS AND A DISCUSSION OF MODULAR POWER ELECTRONICS, COMPONENT
MANUFACTURING, AND POWER ELECTRONIC APPLICATIONS
Welcome and Introductory Remarks, Mark Rawson, California Energy Commission
8:00 - 8:10
Power Electronics for Utility Applications at the Department of Energy, Imre Gyuk, DOE
8:10 - 8:25
Power Electronics Research Assessment, Forrest Small, Navigant
8:25 - 8:40
Session 1: Experience with Modular Power Electronics - Chair: Bernard Trenton, CEC
EXPERIENCE WITH MODULAR POWER ELECTRONICS FROM THE POWER ELECTRONICS BUILDING BLOCK
PROGRAM, INTEGRATED POWER ELECTRONICS MODULES AND BRICKS AND BUSES APPROACH
8:40 - 9:00
9:00 - 9:20
9:20 - 9:40
9:40 - 10:00
10:00 - 10:30
PEBB Program Experience, Terry Ericsen, Office of Naval Research
Integrated PEBB Modules, Converters, and Systems, Fred Wang, Virginia Tech
Bricks and Buses, Giri Venkataramanan, University of Wisconsin
General Discussion
BREAK
Session 2: Advanced Concepts and Components - Chair: Dick DeBlasio, NREL
ADVANCED CONCEPTS FOR POWER ELECTRONICS CONVERTER DESIGNS INCLUDING MATRIX AND MULTI-PORT
CONVERTER, MANUFACTURING POWER ELECTRONIC COMPONENTS AND ADVANCED FUNCTIONALITY FOR
DISTRIBUTED ENERGY APPLICATIONS.
10:30 - 10:50
10:50 - 11:10
11:10 - 11:30
11:30 - 12:00
Advanced Topologies, Ned Mohan, University of Minnesota
Integrated Modules Simplify Systems Design, John Mookken, SEMIKRON Inc.
Power Electronic Interfaces, Ben Kroposki, NREL
General Discussion
12:00 – 1:00 Lunch (on your own)
Session 3: Modular Power Electronics Distributed Energy Applications - Chair: Jose Palomo, CEC
HIGH VOLUME POWER ELECTRONICS DESIGN AND MANUFACTURING CHALLENGES AS WELL AS CURRENT
DISTRIBUTED ENERGY APPLICATIONS THAT USE THE MODULAR APPROACH
1:00 – 1:20
1:20 – 1:40
1:40 – 2:00
2:00 – 2:30
2:30 – 3:00
Modular and Scalable Power Converters in the UPS Industry, Ian Wallace, Eaton
Distributed Energy Applications Leverage High Volume, Modular Power Converters- Perry Schugart American Superconductor
Modular Inverters for Distributed Generation, Matt Zolot, UQM
General Discussion
BREAK
Session 4: Chair: Power Electronics for Distributed Energy Applications - Chair: Holly Thomas, NREL
CURRENT POWER ELECTRONICS IN THE RENEWABLE AND DISTRIBUTED ENERGY MARKETS
3:00 – 3:20
3:20 – 3:40
3:40 – 4:00
4:00 – 4:20
4:20 – 5:00
Magnetek Power Electronics - Alex Levran, Magnetek, Inc.
Xantrex Power Electronics for Renewable Energy System Applications – Ray Hudson, Xantrex
Power Electronics for DER & Renewable Applications, Jonathan Lynch, Northern Power Systems
SMA Power Electronics – Kent Sheldon, SMA
Wrap-up for the day and general discussion
28
Appendix B. List of Attendees
Allen, Jennifer
California Energy Commission
1516 9th St., MS 43
Sacramento, CA 95814-5512
(916) 653-0291
[email protected]
Erickson, Robert
University of Colorado – Boulder
Engineering Center, OT 356 425 UCB
Boulder, CO 80309-0425
(303) 492-7003
[email protected]
Alvarez, Manuel
Southern California Edison
(916) 441-2369
[email protected]
Ericson, Terry
ONR
875 North Randolph St., Suite 1425
Arlington, VA 22203-1995
Balog, Robert
Smart Spark Energy Systems
60 Hazelwood Drive
Champaign, IL 61820
(217) 344-6044
[email protected]
Gyuk, Imre
Department of Energy – Office of
Electricity Delivery & Energy Reliability
1000 Independence, OE-10
Washington, DC 20586
(202) 586-1492
[email protected]
Basso, Thomas
NREL
1617 Cole Blvd.
Golden, CO 80401-3393
(303) 275-3753
[email protected]
Hingorani, Narain
26480 Weston Drive
Los Altos Hills, CA 94022,
(650) 941-5240
[email protected]
Briere, Michael
International Rectifier
1521 E. Grand Ave.
El Segundo, CA 90245
(310) 252-7124
[email protected]
Hudson, Raymond
Xantrex Technology Inc.
161-G South Vasco Road
Livermore, CA 94551
(925) 245-5421
[email protected]
DeBlasio, Richard
NREL
1617 Cole Blvd.
Golden, CO 80401-3393
(303) 275-4333
[email protected]
Johnson, Robert
Cal Poly, San Luis Obispo
1228 Bordeaux St.
Livermore, CA 94550
(805) 550-7535
[email protected]
29
Kramer, Bill
NREL
1617 Cole Blvd.
Golden, CO 80401
(303) 275-3844
[email protected]
Mohan, Ned
University of Minnesota Twin Cities
Campus - Department of Electrical and
Computer Engineering
200 Union St. S.E.
Minneapolis, MN 55455
(612) 625-3362
[email protected]
Kroposki, Benjamin
NREL
1617 Cole Blvd.
Golden, CO 80401-3393
(303) 275-2979
[email protected]
Mookken, John
SEMIKRON Inc.
11 Executive Drive
Hudson, NH 03051
(603) 883-8102 Ext. 145
[email protected]
Kulkarni, Pramod
California Energy Commission
1516 9th St., MS 43
Sacramento, CA 95814-5512
(916) 654-4637
[email protected]
Nichols, David
Rolls-Royce Fuel Cell Systems
13030 Heatherstone Circle
Pickerington, OH 43147
(614) 755-2768
[email protected]
Levran, Alexander
Magnetek
8966 Mason Ave.
Chatsworth, CA 91311
(818) 727-2216
[email protected]
Palomo, Jose
California Energy Commission
1516 9th St., MS 43
Sacramento, CA 95814-5504
(916) 654-4388
[email protected]
Lutz, Jon
UQM Technologies Inc.
7501 Miller Drive, P.O. Box 439
Frederick, CO 80530
(303) 278-2002
[email protected]
Pink, Christopher
NREL
1617 Cole Blvd.
Golden, CO 80401-3393
(303) 275-3758
[email protected]
Lynch, Jonathan
Northern Power
182 Mad River Park
Waitsfield, VT 05673
(802) 583-7224
[email protected]
Rawson, Mark
California Energy Commission
1516 9th St., MS 43
Sacramento, CA 95814-5504
(916) 654-4671
[email protected]
30
Schugart, Perry
American Superconductor
15775 W. Schaefer Court
New Berlin, WI 53151
(262) 901-6036
[email protected]
Thomas, Holly
NREL
1617 Cole Blvd.
Golden, CO 80401-3393
(303) 275-3755
[email protected]
Sheldon, Kent
SMA America
P.O. Box 5049
Livermore CA 94551-5049
(530) 273-4895
[email protected]
Thompson, Chris
Xantrex Technology Inc.
8999 Nelson Way
Burnaby, BC Canada V5A 4B5
(604) 422-2500
[email protected]
Small, Forrest
Navigant Consulting
77 South Bedford St., Suite 400
I Burlington, MA 01803
(781) 270-8455
[email protected]
Treanton, Bernard
California Energy Commission
1516 9th St., MS 43
Sacramento, CA 95814-5504
(916) 654-4512
[email protected]
Smedley, Gregory
One-Cycle Control Inc.
13844 Alton Parkway, Suite 137
Irvine, CA 92618
(949) 275-0581
[email protected]
Vartanian, Charlie
Southern California Edison
1000 Portero Grande
Monterey Park, CA 91755
(323) 889-5516
[email protected]
Soinski, Art
California Energy Commission
1516 9th St., MS 43
Sacramento, CA 95814-5504
(916) 654-4674
[email protected]
Vaughn, Amy
NREL
1617 Cole Blvd.
Golden, CO 80401
(303) 275-3863
[email protected]
Steeley, William
EPRI Research Institute
3420 Hillview Ave.
Palo Alto, CA 94304-1395
(650) 855-2203
[email protected]
Venkataramanan, Giri
University of Wisconsin
1415 Engineering Drive
Madison, WI 53706
(608) 262-4479
[email protected]
31
Wallace, Ian
Eaton Corp., Innovation Center
4201 North 27th St.
Milwaukee, WI 53216-1897
(414) 449-6238
[email protected]
Wang, Fred
Virginia Tech
645 Whittemore Hall (Mail Code 0179)
Blacksburg, VA 240612
(540) 231-8915
[email protected]
Wang, Warren
Navigant Consulting
One California Plaza, 300 S. Grand Ave.
29th Floor
Los Angeles, CA 90071
(213) 670-3248
[email protected]
Zolot, Matthew
UQM Technologies Inc.
7501 Miller Drive
Frederick, CO 80530
(303) 278-2002 x1153
[email protected]
32
Appendix C. Speaker Biographies
Imre Gyuk, U.S. Department of Energy
Dr. Imre Gyuk is program manager of the U.S. Department of Energy’s Energy Storage and
Power Electronics Research Program in the Office of Electricity Distribution and Energy
Reliability. The program funds work on a variety of technologies, such as advanced batteries,
flywheels, supercapacitors, and power electronics. The program works with California
Energy Commission on a joint $9.6 million energy storage initiative.
Forrest Small, Navigant
Forrest Small is an associate director in the Energy Practice of Navigant Consulting. His
professional focus is on the development and implementation of technology-based solutions
for electric power delivery through work with utilities, equipment suppliers, and public sector
agencies. Mr. Small has more than 15 years of experience in the electric power industry and
has worked in consulting, open access transmission operations, transmission and distribution
planning, and advanced power system engineering.
Terry Ericsen, Office of Naval Research
Terry Ericsen is the program manager for the ONR. He has led the development of the Power
Electronic Building Block Program for the office.
Fred Wang, Virginia Tech
Dr. Fred Wang is an associate professor and the technical director at CPES, Virginia Tech.
Prior to joining CPES five years ago, he worked for GE for 10 years as a power systems
application engineer, a motor drive design engineer, and a power electronics R&D manager.
His interests are power converters, power systems, and motor drives.
Giri Venkataramanan, University of Wisconsin
Giri Venkataramanan studied electrical engineering at Government College of Technology,
Coimbatore, India; Caltech; and the University of Wisconsin, Madison. After teaching
electrical engineering at Montana State University, Bozeman, he returned to the University of
Wisconsin, Madison, as a faculty member in 1999, where he continues to direct research in
various areas of electronic power conversion as an associate director of the Wisconsin
Electric Machines and Power Electronics Consortium. He holds five U.S. patents and has coauthored more than a hundred technical publications. His interests are in the areas of
microgrids, wind energy, power converter topologies, dynamics and control, and community
engineering projects.
33
Ned Mohan, University of Minnesota
Ned Mohan is Oscar A. Schott Professor of Power Electronics at the University of Minnesota
in Minneapolis, Minnesota, where he has been teaching for the past 31 years. He has
numerous patents and publications in the fields of power electronics, electric machines and
drives, and power systems, in which he has written five books.
John Mookken, SEMIKRON Inc.
John Mookken’s career in power electronics began in 1999 as an applications and test
engineer working on a U.S. Department of Energy-funded automotive power electronics
program. In 2004, he joined SEMIKRON USA as a product manager for advanced integrated
power modules. He is also the project director of the U.S. Department of Energy-funded
AIPM program at SEMIKRON. He completed his MS in electrical engineering at the
University of South Carolina.
Ben Kroposki, NREL
Ben Kroposki is the Distributed Energy Systems Integration supervisor at NREL. His
expertise is in the design and testing of renewable and distributed power systems, and he has
produced more than 40 publications in this area. Kroposki received his BS and MS in
electrical engineering from Virginia Tech and is pursuing his Ph.D. in electrical engineering
at Colorado School of Mines. He is a senior member of the IEEE and a registered
professional engineer in Colorado.
Ian Wallace, Eaton
Ian Wallace is a senior specialist at Eaton Corp.’s Innovation Center, a research and
development center in Milwaukee, Wisconsin. He has 16 years experience in electric power
conversion designing and developing power electronics and control systems for industrial,
aerospace, and power quality markets.
Perry Schugart, American Superconductor
Perry Schugart joined American Superconductor in December 2000 as director of Sales and
Marketing of the company’s Power Electronics Business Unit. In this position, Schugart is
responsible for the development, marketing, sales, and distribution of the company’s power
electronic converter products. Prior to joining American Superconductor, Schugart held
increasingly senior positions with International Rectifier, most recently as director of Sales
Development. An Illinois native, Schugart holds a bachelor's of science degree in physics
from the University of California, Santa Barbara.
Matt Zolot, UQM
Matt Zolot is a power electronics engineer at UQM, where he works on the development of
modular inverter designs. Prior to working at UQM, Matt was with NREL, where he worked
on power electronics for the transportation sector. Matt graduated from Georgia Tech with a
BS in electrical engineering and is currently pursuing a master’s degree in electrical
engineering at the Colorado School of Mines.
34
Alex Levran, Magnetek Inc.
Alex Levran is the executive vice president and chief technology officer for Magnetek. He
manages engineering activities in the design of power supplies, generators and motors,
military and commercial power conversion, and alternative energy products. He also
coordinates engineering activities in Europe and the United States, creates technology
roadmaps, and engages in acquisitions. Prior to his work at Magnetek, he worked for Marlin
Gernin and Teledyne. Levran has also been a visiting professor at the University of
California, Los Angeles, and is currently on the board of directors for the Power Sources
Manufacturers Association.
Ray Hudson, Xantrex
Ray Hudson is the vice president of Advanced Technology for Xantrex.
Jonathan Lynch, Northern Power Systems
In his role as chief technology officer of Northern Power, Mr. Lynch manages R&D and new
product development efforts. Lynch is responsible for the identification and development of
new technology and products to aid Northern’s growth across its business areas, which
include products and services for remote industrial, onsite generation, and renewable-based
power systems. Prior to joining Northern, Lynch was employed as a design engineer at
Carrier Corp., where he modeled and designed high-performance refrigeration systems and
controls for transportation applications. Lynch graduated from Stevens Institute of
Technology with a BSME degree with honor.
Kent Sheldon, SMA America
Kent Sheldon has been involved in the renewable energy industry for 10 years with Kenetech
Windpower, Trace Technologies, Xantrex Technologies, and SMA America. During this
time, he has worked as a project engineer for a variety of three-phase, grid-tied photovoltaic
and large hybrid power centers; an engineering manager for the PV Series inverter family;
and, currently, as a sales support manager.
35
Appendix D. Workshop Presentations
36
Advanced Power Electronics Interfaces
for
Distributed Energy Workshop
August 24, 2006
Energy Systems Integration Research Program
California Energy Commission
and
National Renewable Energy Laboratory
Mark Rawson
Energy Systems Integration Research Program
California Energy Commission
California’s PIER Program
• Public Interest Energy Research (PIER)
– Established in 1996 as part of deregulation of electric utilities
– At least $62.5M collected annually from investor-owned utility ratepayers for
"public interest" energy R&D
– Focuses on R&D not adequately provided by competitive and regulated
markets
• Comprised of 7 research areas
– Environmentally Preferred Advanced Generation
– Renewable Generation
– Building End Use Efficiency
– Industrial, Agricultural and Water End Use Efficiency
– Environmental
– Transportation
– Energy Systems Integration
• New, complementary natural gas public interest program established in
2005 that is expected to grow to $24M by 2009
2
37
ESI Approach
ESI uses systems engineering approach that requires looking at the big
picture in a holistic fashion.
•
Central Station
Power Plant
Robust generation
& transmission
Transmission
Distribution
Substation
Distribution
Distribution
Transformer
Customers
Microgrid
Source: CERTS Microgrid
Advanced
distribution is
used to provide
local reliability
and flexibility,
robustness of
T&D and
promote the use
of demand
response, CHP
and renewable
intermittent
resources.
•
Demand Response
Addressing T&D and load growth issues
necessitates a coordinated effort
– Integrate EE, DR, DG-CHP, renewables
(large and DG), and storage into local
energy system designs
– Demonstrate the benefit to utilities,
regulators and ratepayers
– Optimize integration strategies to target
peak load and grid utilization
Advances in the T&D system and on the load
side can get us to this new vision for the
future
– Sensors and monitoring
– Power electronics
– Communication and controls
– Intelligent automated systems
– Real time operations of the T&D system
Science and technology can transform the 19th century electricity system
into the 21st century information age if we dare to make it happen.
3
ESI Strategic Objectives Aligned with Policy Drivers
IEPR, EAP, California Solar Initiative, RPS all identify needs that ESI is
focused on finding solutions for.
Integrated Electricity System that is Reliable and Secure
PIER
Strategic
Objectives
1. Enable optimal integration of renewables, distributed generation,
demand response, and storage to the power system.
2. Improve capacity, utilization, and performance of transmission and
distribution system.
3. Improve cost and functionality of components to integrate demand
response, distributed generation, and electricity storage into the
system.
4. Improve security and reliability of electricity system.
5. Support improvement of tariffs and regulations for demand response,
distributed generation, storage, and renewables.
6. Facilitate transmission siting process.
7. Develop knowledge base for future decision-making and informed delivery,
integration, and infrastructure policy relative to electricity.
Source: PIER 2007-2011 Electricity
Research Investment Plan
Our comprehensive portfolio of T, D, DR, DER Integration, Storage and
Security research projects is supporting these strategic objectives.
4
38
Cost of Power Electronics
DER total capital costs
Power electronics are part of
key DER technologies, and
represent a significant portion
of the capital costs.
100%
80%
DER Capital Cost
$/kW
Power Electronics
% of DER cost
Microturbine
$900 - $1,800
35% - 45%
Wind Turbine
$1,000 - $4000
25% - 40%
Fuel Cell
$3,000 - $6,000
10% - 30%
Photovoltaics
$6,000 - $10,000
10% - 25%
DER Type
60%
40%
20%
0
Microturbine
Cost reductions in power
electronics will reduce the overall
cost of DER.
Wind
Turbine
Power Electronics
Fuel Cell
PV
Other Capital Costs
Source: NREL
5
APEI Initiative Timeline
APEI Initiative is anticipated to be a collaborative ~$20M, 6 years effort.
Project
Year 1
Generation 1
Advanced
Power
Electronics
Interface
Build Prototype
Version
Solicitation #1
Year 2
Year 3
Build
Commercial
Version
Small Demo
Year 4
Year 5
Evaluate
Performance
Large Demo
Inputs from
Topical
Workshops
Generation 2
Advanced
Power
Electronics
Interface
Topical
Workshop on
advanced
components
Year 6
Design of
Generation 2
Solicitation #2
Build Prototype
Version
Build
Commercial
Version
Evaluate
Performance
Demo
6
39
Purpose and Focus of Workshop
Purpose
• To provide industry stakeholders with an update of the status of
technologies and issues in power electronics
Focus
• Development of advanced power electronic interfaces for Distributed
Energy Applications
Results from this workshop will help PIER and NREL structure our
strategies for the upcoming APEI Initiative.
7
40
Power Electronics
for Utility Applications
at the Department of Energy
________________________________
IMRE GYUK, PROGRAM MANAGER
ENERGY STORAGE AND POWER ELECTRONICS
RESEARCH, DOE
CEC-PE 8-24-06
Office of Electricity Distribution
and Energy Reliability
DOE
Utility Power Electronics funded
through the Energy Storage Program
but relevant for all Distributed Generation.
41
THE PQ PROBLEM:
• The Digital Economy is vulnerable to Power
Quality (PQ) events such as micro-outages of a
few milli-seconds and voltage sags of a few
percent
• PQ events are common and cost the U.S. economy
an estimated $52 billion
• System should be factory integrated and tested and
allow plug and play installation
Domain of Storage
175
Voltage Magnitude (%)
150
125
100
75
50
25
0
10
-1
10
0
10
1
10
2
10
3
10
4
Duration (60 Hz Cycles)
1.6 ms.
16 ms.
160 ms.
1.66 sec.
16.6 sec.
2.7 min.
CBEMA Magnitude - Duration Scatter Plot (EPRI Data)
42
• Full power must be available in 4 milliseconds =
1/4 cycle for seamless power supply
• Energy should last for 15 -30 sec to cover 95% of
outages and allow backup generation to ramp up
• Required development of a compact 250kW
inverter (Omnion, S&C)
• Testing at PG&E facility. R&D 100
2 MW – 15 sec Mobile Battery System
43
10 MW - 30 sec System at AZ Microchip Plant
S&C Power Conditioning System for a
1.2 MW – 6 hour NaS System for Peak Shaving
44
SBIR Projects :
• Optically Isolated Inverter, (ONR co-funding)
R&D 100 Award
•
High Current Inverter with Advanced Heat
Exchanger
•
Low Cost Modular Highly Reliable Inverter
Development of Emitter
Turn-off (ETO) Switch
Need for a Switch that is
Faster, More Powerful,
and Cheaper than
Conventional Switches
45
CURRENT HIGH-POWER SWITCH TECHNOLOGY
1500
Power MW
45
SCR
Target Region
ETO
15
5
GTO
IGBT
50
500
Switching frequency (Hz)
5000
16 MW ETO Switch
• Developed at Virginia Tech – NC State
• 15-20 times faster than GTO
• 3 times the power and less expensive
than IGBT
• Development of Transmission
Stabilization Device Planned with TVA
46
Emitter Turn Off Thyristor
R&D 100 Award Winner
Transformerless STATCOM
with Energy Storage
DOE, TVA, NC State University,
EPRI, EPRI-Solutions, Sandia
To provide 4-quarter control with Real and
Reactive Power
47
69 kV
PCC
13.8 kV
Infinite Bus
Load
3-phase coupling
transformer
ƒ Trailer housed close to
customer
ƒ Nominal 30 / 60 MVA
2 second surge.
ƒ Energy storage: 15 MW,
2 second active power
Supercaps
ETO-Based Converter
The BPA Wind Project:
ƒ A 48 MW Wind Farm on the BPA Grid
ƒ Extensive Complaints by other
Customers about poor PQ
ƒ Proposed Solution by ETO Statcom
48
Condon Wind Voltage, July 14-Aug.14
5 minute samples
Wind Integration
34.5 kV
69 kV
PCC
Grid
48MW Wind Farm
ƒ
ƒ
ƒ
ƒ
ƒ
3-phase coupling
transformer
Condon, OR Wind Farm
Weak grid
Pronounced PQ issues
10 MVA Statcom
BPA, DOE, TVA, EPRI
Supercaps
49
ETO-Based Converter
FY 2008 Science, Technology,
and Environment Briefing
Specific Areas for Investment and
Management Attention – Plus ups
• Electricity
storage
• Carbon capture & storage
• Unconventional fossil
• Bioenergy
• Adaptive grid controls
• Power electronics
• Superconductivity
• Solar energy utilization
• Buildings systems
• Complex systems
assessment
Power Electronics and Advanced
Materials
Near Term Options
< 2010
• ETO deployment
• Improved thermal
management
systems with novel
materials
Through 2015
• Silicon carbide
switch
• High temperature
materials
• Ionic fluids for
electrolytes
Through 2025 & beyond
• Advanced wide
band gap systems
deployment
• Nano-structured
materials and
devices
• Diamond switch
50
SBIR Projects :
• High Power Densit y (100 kW) Silicon
Carbide (SiC) Three Phase Inverters,
Arkansas Power Electronics (FY06)
•
Advanced Power Converter System
Using High Temperature, High Power Density
SiC Devices, Aegis Technology (FY06)
•
Wide Band Gap, High Voltage, High
Frequency Switches (FY07)
Energy Storage and Power Electronics
Program Peer Review
Nov. 2 – 3, 2006, Washington, DC
http://www. sandia.gov/ess/
51
DER Integration Research Program
Power Electronics Research Assessment
Executive Summary
Advanced Power Electronics Interfaces for DE Workshop
August 24, 2006
Public Interest Energy Research Program
California Energy Commission
1
Research Assessment Scope
In 2004, the CEC asked NCI to provide input into the Distributed Energy
Resources Integration research agenda for power electronics.
•
Objective
– To identify gaps in the research programs being conducted by government
organizations and private industry in order to provide guidance to the PIER DER
Integration Research Program as it develops its research agenda in the area of
Power Electronics technologies used in DER applications.
•
Scope
– Included the identification and assessment of research gaps in Power Electronics
technologies used in DER applications. The analysis focused on Power
Electronics technologies used in distributed generation systems (e.g., fuel cells,
PV and microturbines) and distributed energy applications (e.g., inverters,
uninterruptible power supplies and energy storage).
– Included recommendations for specific research initiatives and approaches.
2
Power Electronics Research Assessment Executive Summary, 08/24/2006
52
Summary of Recommendations
NCI recommended that the CEC support three research initiatives and act as
a catalyst for a systems approach to power electronics.
High Priority Research Initiatives
•
•
•
Standardize the interface between power electronics systems and the grid
Standardize and improve the interoperability of power electronics components and
systems
Improve the scalability and modularity of power electronic systems and
components
Catalyst for Systems Approach
CEC should drive for a systems approach:
• Large projects should include all stakeholders that develop the various components
and systems rather than just the final integrator/packager of the technologies.
• Smaller projects should be encouraged to exchange research needs ideas and
results. These projects should be coordinated to effect the larger PE systems.
• CEC should begin by supporting the development of a forum to encourage a
dialogue between different stakeholders. The initial topic could discuss how to move
toward common standards and modularity.
3
Power Electronics Research Assessment Executive Summary, 08/24/2006
Key Business Needs and Technology Challenges
The key business needs for DER power electronics are reducing costs
and improving reliability. To support these an effective R&D program
must address three technology challenges.
Key
Business
Needs
Technology
Challenges
•
•
•
•
•
Reduce costs – power electronics can account for up to 40% of
the costs of a DER system
Improve reliability – current level of performance may prevent the
long term commercial penetration of DER using power electronics
Lack of standardization and the inter- and intra-operability of
power electronic systems, components and the grid
Need power electronic devices that are modular and scalable
Need for improvements (R&D) in power electronic system
packages
4
Power Electronics Research Assessment Executive Summary, 08/24/2006
53
Key Research Initiatives
The technology challenges can be overcome by supporting ten key
research initiatives.
1.
2.
3.
4.
5.
6.
7.
8.
Increase the efficiency of power electronic systems
Standardize the interface between power electronics systems and the grid
Improve the thermal management characteristics of power electronic systems
Minimize the harmonic distortions of power electronic systems
Improve the durability of power electronic systems and components
Reduce the complexity of power electronic systems
Improve the manufacturability of power electronic systems and components
Standardize and and improve the interoperability of power electronics components
and systems
9. Improve the scalability / modularity of power electronic systems and components
10. Minimize the system package size of power electronics
5
Power Electronics Research Assessment Executive Summary, 08/24/2006
Initiative Mapping
Initiatives that the CEC should consider are those that have a large
technology gap, high public benefit and high DER applicability.
High
Research Initiatives
4
1.
2
2.
3.
Public
Interest
8
4.
9
5.
10
6.
1
5
7.
3
8.
6
7
Low
9.
Low
Technology Gap
Relative
Distributed Energy Resources Impact
and Applicability
High
10.
Increase the efficiency of power electronic
systems
Standardize the interface between power
electronics systems and the grid
Improve the thermal management
characteristics of power electronic systems
Minimize the harmonic distortions of power
electronic systems
Improve the durability of power electronic
systems and components
Reduce the complexity of power electronic
systems
Improve the manufacturability of power
electronic systems and components
Standardize and improve the interoperability
of power electronics components and
systems
Improve the scalability / modularity of power
electronic systems and components
Minimize the system package size of power
electronics
Significant gap
Moderate gap
Little or no gap
6
Power Electronics Research Assessment Executive Summary, 08/24/2006
54
Top Three Initiatives for the CEC
Of the ten research initiatives identified, three are the most attractive for
the CEC:
2
Standardize the interface between power electronics systems and the grid
• A significant research and funding gap exists
• This initiative is very important for both DER and Public Benefit
• PIER could play an instrumental role in bringing together the key stakeholders to develop necessary and
acceptable interface standards for DER power electronics
8
Standardize and improve the interoperability of power electronics components and systems
• A moderate research and funding gap exists, and this was raised as a critical issue for power electronics
• Private industry would likely have great difficulty organizing itself to address this challenge
• PIER could facilitate the bringing together of key stakeholders to develop interoperable components and
systems
Improve the scalability / modularity of power electronic systems and components
9
• A significant research and funding gap exists
• This is initiative is very important for DER and moderately so for increasing public benefit
• The impact of this research initiative is cross-cutting as increased scalability and modularity should lead to
improvements in the reliability and cost of DER power electronics
7
Power Electronics Research Assessment Executive Summary, 08/24/2006
End of Executive Summary
8
55
DER Power Electronics Context
A DER power electronics unit is a system that incorporates packaged
devices and controls. The level of complexity depends on the application.
DER Power Electronics Unit
System / Packaging
Generation
Source
Control
Control
Device
1
Device
2
Device
3
Load
Control
Grid
9
Activity Areas
The power electronics activity can be classified into three fundamental
areas: Devices, System / Packaging, and Controls.
Devices
System / Packaging
Controls
Description
• The discrete switching
devices themselves
• Current technology is
silicon-based, with siliconcarbide technology the
most likely successor in
the coming years.
• The arrangement of
devices
• Devices can be can be
used individually or in
combinations depending
on the application
• Hardware and software to
manage the power
electronics system as well
as monitor and respond to
changing conditions
Examples
• Metal Oxide
Semiconductor Field Effect
Transistor (MOSFET)
• Insulated Gate Bipolar
Transistor (IGBT)
• Gate Turn-Off Thyristor
(GTO)
• Rectifier
• Inverter
• Converter
•
•
•
•
Devices:
• IGCT switch
• Super GTO switch
• ETO switch
Materials
• Silicon Carbide
• Diamond
• ETO
• Advanced topologies
utilizing higher
voltage/capacity devices
• Thermal management
• Packaging
• Plug and play
interconnection of DER
• Autonomous control
• Peer to peer
communications
Current R&D
Sensors
Processors
Communications
Software
10
56
Research Gap Analysis
Gap Terminology
The degree to which individual research initiatives are currently being
pursued was categorized based on comments and feedback.
• Significant gap: Few companies or entities are adequately pursuing this strategy
at a level that will likely ensure the strategy has a reasonable chance of success to
help resolve the issue it is addressing. This could indicate an area that has been
overlooked or just emerging as a viable strategy.
• Moderate gap: There are several companies and/or entities pursuing this strategy.
Continued and additional activity is likely required to ensure the strategy has a
reasonable chance of success to help resolve the issues it is addressing.
Strategies were also given a moderate gap rating if it is deemed a strategy that is
not appropriate or feasible to pursue at this time.
• Little or no gap: There are many companies and/or entities pursuing this strategy.
The current level of activity is likely appropriate to ensure the strategy has a
reasonable chance of success to help resolve the issue it is addressing. Little
additional work beyond what is currently funded is needed.
11
Research Gap Analysis
Research Initiative 1
Research Initiative 1
1
Increase the efficiency of power electronic systems
Increasing the efficiency of power electronic systems is a key concern given its impact on the effectiveness of power
electronics solutions, and there are multiple projects currently underway that are addressing this issue. Nevertheless,
given the fundamental importance of this top, additional support may be warranted.
Public benefit: This initiative could provide a competitive advantage, but benefits are primarily to the manufacturer.
Relative DER Applicability: This initiative is a crosscutting issue, but there is little room left for economic or reliability improvements to
occur as a result of increased efficiency.
Estimated Total Funding Needed
$20 M
Estimated Current Public Support
2
2.5
$1.9 M
Research Projects That Address Initiative
A
Optically Isolated 5MW Inverter. Improve reliability by
developing a new, highly efficient (99%+) inverter design
that utilizes optical sensing and control, DSP control
algorithms and HVIGBT devices.
J
High Reliability Inverter Development. Reduce the cost and improve
reliability by developing an inverter that operates like a convention
hard-switched inverter with no limitations on switching timings or
additional control complexity.
C
Compact Diode-Clamped Multilevel Converter. Improve
reliability and efficiency by developing a diode-clamped
multilevel inverter that share a common DC bus
L
H
Silicon Carbide Power Electronics for Utility Application.
Improve the reliability of power electronics by researching
the benefits and applications of SiC.
Digital Control of PWM Converters. Improve reliability by minimizing the
power dissipation of the converter by dynamically adjusting parameters such
as the synchronous rectification dead time and the current sharing in multiphase converters.
O
Diamond Tip Emitters. Improve the reliability and efficiency of power
electronics through the use of diamond tipped emitters
Significant gap
Moderate gap
Little or no gap
12
57
Research Gap Analysis
Research Initiative 2
Research Initiative 2
2
Standardize the interface between power electronics systems and the grid
Standardization of a power electronic grid interface for DER is critical to increasing the penetration of DER. Several
projects are developing technology that will support this initiative, but only one project directly addresses the issue of
standardization. Moreover, the current public support is a small fraction of the estimated total funding required.
Public benefit: Very limited incentives, and all classes of stakeholder (including ratepayers) will benefit.
4.5
Relative DER Applicability: This initiative is unique to DER and there could be a significant impact to DER through reduced installation
4.5
costs and improved reliability.
Estimated Total Funding Needed
$15 M
Estimated Current Public Support
$1.5 M
Research Projects That Address Initiative
C
Compact Diode-Clamped Multilevel Converter. Improve reliability by developing a diode-clamped multilevel inverter that share a common
DC bus Their unique structure allows them to span high voltage without the use of transformers and with no voltage sharing problems.
G
Distributed Energy Interface. Improve the reliability of power electronics by improving the power flow between energy resources and the
grid through the use of power electronic interfaces.
J
High Reliability Inverter Development. Reduce the cost and improve reliability by developing an inverter that operates like a conventional
hard-switched inverter with no limitations on switching timings or additional control complexity.
N
ETO Thyristor Development. Reduce cost and improve reliability by utilizing integrated power electronic modules composed of
standardized components (instead of custom designed systems) in the development of ETO Thyristors.
V
Static Inverter Type Testing. Improve reliability by developing a procedure type and verification testing of static inverter.
Significant gap
Moderate gap
Research Gap Analysis
Little or no gap
13
Research Initiative 3
Research Initiative 3
3
Improve the thermal management characteristics of power electronic systems
There are only a few projects addressing the thermal management issue, yet this is a major issue surrounding power
electronics. Several of the people interviewed raised this topic as an area requiring further research. Thermal
management can be controlled or improved through both material and mechanical advances and should increase both
performance and reliability.
Public benefit: This initiative is more of a product attribute, and the benefits are not widespread.
1.5
Relative DER Applicability: This initiative could reduce package size and manufacturing costs. Reliability is increased through the
reduction in failures associated with poor thermal management.
Estimated Total Funding Needed
$10 M
Estimated Current Public Support
2.5
$2 M
Research Projects That Address Initiative
H
Silicon Carbide Power Electronics for Utility Application. Improve the reliability of power electronics by researching the benefits and
applications of SiC.
R
Thermal Management for Power Electronics. Increase the reliability of power electronics by improving the thermal characteristics with a
combination of high--temperature materials and advanced cooling strategies
O
Diamond Tip Emitters. Improve the reliability and efficiency of power electronics through the use of diamond tipped emitters
Significant gap
Moderate gap
Little or no gap
14
58
Research Gap Analysis
Research Initiative 4
Research Initiative 4
4
Minimize the harmonic distortions of power electronic systems
There was only one project identified that is focusing on reducing the harmonic distortions of power electronics, yet a
significant amount of research has been done in this area in the past. Industry standards already exist to address this
issue.
Public benefit: There is significant public interest and multiple stakeholder classes will benefit.
5
Relative DER Applicability: There is minimal impact on DER applications.
2
Estimated Total Funding Needed
$2 M
Estimated Current Public Support
$0.5 M
Research Projects That Address Initiative
D
Multilevel Universal Power Conditioner. Improve the reliability of power electronics through the development of a multilevel universal
power conditioner.
I
Harmonic Elimination Technique and Multilevel Converters: Control a multilevel inverter in such a way that it is an efficient, low total
harmonic distortion (THD) inverter that can be used to interface distributed dc energy sources to a main ac grid.
Significant gap
Moderate gap
Research Gap Analysis
Little or no gap
15
Research Initiative 5
Research Initiative 5
5
Improve the durability of power electronic systems and components
A significant research gap exists as relatively few projects are actively concentrating on increasing the durability of power
electronic components and systems. While power electronics system manufacturers are likely to be actively conducting
internal research to improve the reliability of their products, a more systemic approach with public funding support may
yield benefits that can be shared industry-wide.
Public benefit: This initiative benefits primarily manufacturer and customer.
2
Relative DER Applicability: This initiative has high applicability to DER, and improves reliability.
4
Estimated Total Funding Needed
$20 M
Estimated Current Public Support
<$0.5 M
Research Projects That Address Initiative
None
Significant gap
Moderate gap
Little or no gap
16
59
Research Gap Analysis
Research Initiative 6
Research Initiative 6
6
Reduce the complexity of power electronic systems
The DOE is funding several research projects to reduce the complexity of power electronics, but many comments were
raised about the significance of this issue. This is a cross-cutting issue that will help reduce costs, ease manufacturing,
and facilitate standardization.
Public benefit: Commercial incentives already exist, and this initiative primarily benefits the manufacturer.
Relative DER Applicability: This initiative is very applicable to DER and significant cost reductions could occur.
Estimated Total Funding Needed
$10 M
Estimated Current Public Support
1
4.5
$2.0 M
Research Projects That Address Initiative
F
Soft Switching Snubber Inverter. Reduce the cost and
improve reliability through the development of advanced
inverter designs that utilize fewer components and
modular electronics.
J
High Reliability Inverter Development. Reduce the cost
and improve reliability by developing an inverter that
operates like a convention hard-switched inverter with no
limitations on switching timings or additional control
complexity.
M
N
ETO Thyristor Development. Reduce cost and improve reliability
by utilizing integrated power electronic modules composed of
standardized components (instead of custom designed systems)
in the development of ETO Thyristors.
O
Diamond Tip Emitters. Improve the reliability and efficiency of power
electronics through the use of diamond tipped emitters
P
Standard Power Electronic Interfaces. Reduce the cost and
improve the reliability of power electronics by developing
standardized approaches for integrating power converter
components.
PV Inverter Products Manufacturing and Design
Improvement. Design a large number of products based
on small number of functional modules to achieve high
manufacturing efficiencies and enhanced product
reliability
Significant gap
Moderate gap
Research Gap Analysis
Little or no gap
17
Research Initiative 7
Research Initiative 7
7
Improve the manufacturability of power electronic systems and components
There is a need for additional research to improve ease of manufacturing. Although the DOE is supporting projects
focused on reducing manufacturing costs, there is still a great deal of research needed. Manufacturing costs are a major
part of total power electronic system costs, and so improving the ease of which a component is manufactured could have
a substantial impact on the attractiveness of power electronics based DER.
Public benefit: Commercial incentives exist, and this initiative primarily benefits the manufacturer.
1
Relative DER Applicability: This initiative is very applicable to DER and significant manufacturing cost reductions could occur.
Estimated Total Funding Needed
$15 M
Estimated Current Public Support
4.5
$1.2 M
Research Projects That Address Initiative
B
Cascade Multilevel Inverter for Utility Applications. Reduce the manufacturing cost and improve reliability and efficiency of multilevel
inverter through the utilization of modular and compact circuit topology
J
High Reliability Inverter Development. Reduce the cost and improve reliability by developing an inverter that operates like a convention
hard-switched inverter with no limitations on switching timings or additional control complexity.
M
PV Inverter Products Manufacturing and Design Improvement. Design a large number of products based on small number of functional
modules to achieve high manufacturing efficiencies and enhanced product reliability
N
ETO Thyristor Development. Reduce cost and improve reliability by utilizing integrated power electronic modules composed of
standardized components (instead of custom designed systems) in the development of ETO Thyristors.
P
Standard Power Electronic Interfaces. Reduce the cost and improve the reliability of power electronics by developing standardized
approaches for integrating power converter components.
Significant gap
Moderate gap
Little or no gap
18
60
Research Gap Analysis
Research Initiative 8
Research Initiative 8
8
Standardize and and improve the interoperability of power electronics components and systems
Standardization of interfaces was identified as a significant barrier surrounding power electronics. There are public and
privately funded projects addressing the standardization / interoperability issue, but research is still needed.
Public benefit: Limited incentives exist, and this initiative could benefit multiple stakeholders.
3
Relative DER Applicability: This is a crosscutting initiative that could yield significant cost and reliability benefits.
4
Estimated Total Funding Needed
$5 M
Estimated Current Public Support
$1.0 M
Research Projects That Address Initiative
C
Compact Diode-Clamped Multilevel Converter. Improve reliability by developing a diode-clamped multilevel inverter that share a common
DC bus Their unique structure allows them to span high voltage without the use of transformers and with no voltage sharing problems.
J
High Reliability Inverter Development. Reduce the cost and improve reliability by developing an inverter that operates like a conventional
hard-switched inverter with no limitations on switching timings or additional control complexity.
N
ETO Thyristor Development. Reduce cost and improve reliability by utilizing integrated power electronic modules composed of
standardized components (instead of custom designed systems) in the development of ETO Thyristors.
Significant gap
Moderate gap
Research Gap Analysis
Little or no gap
19
Research Initiative 9
Research Initiative 9
9
Improve the modularity / scalability of power electronic systems and components
Scalability and modularity were identified as major barriers to improved adoption of power electronics based systems due
to the potential impact on flexibility and cost. There are few projects addressing these issues and significant research is
still needed.
Public benefit: Limited incentives exist, and this initiative could benefit multiple stakeholders.
3
Relative DER Applicability: This initiative is highly applicable to DER and could yield significant cost benefits.
Estimated Total Funding Needed
$10 M
Estimated Current Public Support
4.5
$1.3 M
Research Projects That Address Initiative
J
High Reliability Inverter Development. Reduce the cost and improve reliability by developing an inverter that operates like a convention
hard-switched inverter with no limitations on switching timings or additional control complexity.
P
Standard Power Electronic Interfaces. Reduce the cost and improve the reliability of power electronics by developing standardized
approaches for integrating power converter components.
Q
New Power Electronic Technologies. Reduce costs and improve reliability by developing power electronics products using cutting edge
technology.
Significant gap
Moderate gap
Little or no gap
20
61
Research Gap Analysis
Research Initiative 10
Research Initiative 10
10
Minimize the system package size of power electronics
A moderate research gap exists as several projects identified are trying to minimize the system footprint, and this topic of
obvious concern to manufacturers. The size of the power electronics package impacts the attractiveness of DER
technologies and the ease of integration.
Public benefit: Limited incentives exist, yet this initiative benefits the manufacturer and customer only.
2.5
Relative DER Applicability: This initiative has limited applicability to DER and could actually increase costs.
Estimated Total Funding Needed
$5 M
Estimated Current Public Support
1.5
$0.8 M
Research Projects That Address Initiative
A
Optically Isolated 5MW Inverter. Improve reliability by developing a new, highly efficient (99%+) inverter design that utilizes optical
sensing and control, DSP control algorithms and HVIGBT devices.
B
Cascade Multilevel Inverter for Utility Applications. Reduce the manufacturing cost and improve reliability and efficiency of multilevel
inverter through the utilization of modular and compact circuit topology
NOTE ON MANUFACTURERS: Given that many of the research initiatives are manufacturing or packaging related, it is likely that many DER power
electronics equipment suppliers are actively pursuing internally-funded research supporting many of the research initiatives identified well beyond
research activities co-funded by public sector entities. However, due to competitive nature of the business, very little is known about these internal
research activities.
Significant gap
Moderate gap
Little or no gap
21
Literature Search and Interviews
The first stage of this project was to conduct literature searches and
telephone interviews with research stakeholders.
• Literature search of projects and activities by various stakeholders
–
–
–
–
–
DOE and National Labs
State based R&D funding entities (e.g., CEC, NYSERDA, etc.)
Universities
Manufacturers
Industry organizations and standards bodies
• Telephone interviews with stakeholders and researchers such as:
–
–
–
–
–
–
–
–
Alex Huang of Virginia Tech
Giri Venkataramanan of University of Wisconsin
Keith White and Richard Zhang of GE
Leon Tolbert of Oak Ridge National Laboratory
and the University of Tennessee
Matt Lazarewicz of Beacon Power
Nag Patibandla of NYSERDA
Stan Atcitty of Sandia National Laboratory
Tim Zgonena of UL
–
–
–
–
–
–
–
–
–
Bill Erdman of DUA
Ben Koproski of NREL
Bob Panora of Tecogen
Greg Ball of PowerLight
Ian Wallace of Eaton
Jim Davidson of Vanderbilt University
Perry Schugart of American Superconductor
Scott Samuelsen of UCI
Syed Ahmed of Southern California Edison
22
62
Advanced Electric
Power Systems Thrust
Power Electronic Building Blocks,
PEBB
ONR Experience and Observations
Terry S Ericsen
Program Office for Electrical Science and Technology
Office of Naval Research
[email protected]
Advanced Electric
Power Systems Thrust
Recent Innovations
• Computing Power Increase
• High-Speed and Low-Cost Controllers
• System Simplifying Concepts
63
Advanced Electric
Power Systems Thrust
“System of Systems” Design
Challenges
Today
•
•
•
•
•
Rule Based Design
Standard Parts
Increasing Complexity
Specifications, Documents
Small Samples Statistics
Advanced Electric
Power Systems Thrust
•
•
•
•
•
•
Tomorrow
Relational Based Design
Standard Processes
Increasing Detail
Model is the Specification
Physics Based Analysis
Statistics from All of
Industry
The Changing Role of Simulation
• Today, simulation is used for evaluation
-- Analysis.
– Simulation programs require detailed
design information
• Circuit parameters are entered before
simulation begins.
• Variations in design can be analyzed
• Tomorrow, simulation will become part
of the design process -- Synthesis.
The Model Will Be The Specification
64
Advanced Electric
Power Systems Thrust
Future Design Process
Today
Reality
Modeling
Simulation
Tomorrow
Specs
Design through
Simulation
Reality
Roger Dougal & Antonello Monti, University of South Carolina
Advanced Electric
Power Systems Thrust
The Design Cycle
Customer Designer
Products
Mission:
Performance, Life, &
Cost
Supplier Designer
65
Requirements
Advanced Electric
Power Systems Thrust
Changing World of Models -Dynamics
• Model is the Specification
• Model is the Control
• Model is the Machine
Advanced Electric
Power Systems Thrust
Physics-Based Models are Required
• Product models must be specific
• Requirement models can be general
– In fact, requirement models with very
specific details, in the design phase, can
lead to an overly constrained problem.
66
Advanced Electric
Power Systems Thrust
Complexity
(From “Modeling and Simulation in System Engineering: Whither Simulation Based
Acquisition?” By Andrew P. Sage and Stephen R. Olson, George Mason University)
•
•
•
•
•
The more identical that a model must be to the actual system to
yield predictable results, the more complex the system is.
Complex systems “…have emergence … the behavior of a
system is different from the aggregate behavior of the parts and
knowledge of the behavior of the parts will not allow us to
predict the behavior of the whole system.”
“In systems that are ‘complex,’ structure and control emanate
or grow from the bottom up.”
A system may have an enormous number of parts, but if these
parts “interact only in a known, designed, and structured
fashion, the system is not complex, although it may be big.”
Although a physical system maybe not be complex, if humans
are a part of the system, it becomes complex
Advanced Electric
Power Systems Thrust
Complexity and Simplification
• Complex systems can be simplified by:
– Physics-based partitioning
• Based on the nature of the materials, components, and
manufacturing methods
– Adding intelligent active devices
– Creating controlled and predictable system-states at
physics-based partitions
• All of this increases detail, size, weight, and cost.
• Therefore:
– The size, weight, and cost of these technologies have to be
reduced to enable practical application and simplification.
– Computational abilities and new modeling and simulation
tools are needed to allow for design with increased detail.
67
Development Processes
Advanced Electric
Power Systems Thrust
Commercial
Aerospace
$
Assumptions:
1) Conservative
2) Minimum
Entropy
Production
Performance
(Power Density, Specific Power, Reliability, and etc.)
Advanced Electric
Power Systems Thrust
Technology Maturity Based on the MicroEvolution of Biological Systems
Performance
Michael S. Slocum, “Technology Maturity Using S-curve Descriptors,”
Proceedings of the Altshuller Institute TRIZCON99
New
Technologies
S -- Curve
Existing
Technologies
S -- Curve
Time
68
Advanced Electric
Power Systems Thrust
Management Influences
Concept
Demonstration
Product
Influence
Development
Modeling and Simulation as Early as Possible in a Project
Advanced Electric
Power Systems Thrust
Example: The Electrical System and
The Power Electronics Thesis
• Present electrical power systems are complex.
– At equilibrium, 60Hz. Supplies power to 60Hz loads the
system is stable and predictable.
– If perturbed, the system can become unstable and
unpredictable – bifurcation can occur.
– Humans are needed to operate the system
• Future PEBB based power electronic systems
will not be complex.
– Automation is possible -- reduced operating costs
– Progressive integration -- reduced system costs
– Higher availability due to physics-based health prediction –
reduced maintenance costs
– Increased reliability and life by controlling overstresses
69
Modularization/Integration
Process: CPES Example
Advanced Electric
Power Systems Thrust
Dushan Boroyevich, VA Tech
Integration
System
Optimization
Modules
Partition
Partition
•
•
•
Integration
Optimization techniques
Spatial and functional,
then temporal
Facilitate manufacturing,
achieve volume
•
•
•
Interaction of components:
energy, control
Spatial, then temporal and
functional
Manufacturing volume
Non-desired interactions are non-desired, non-useful,
energy exchanges among system components
Design Challenges,
Partitions and Standard Interfaces
Advanced Electric
Power Systems Thrust
ONR Initiated, S3D
Physical Process Resolution
(more information)
Ships
Systems
Machines
Static
0-D
PhysicalAC
Process
Resolution
Steady-state
Lumped parameters
(more information)
Switching average
2-D
Distributed
parameters
3-D
Switching detail
Computational
Time resolution
(more information)
Physical Process Resolution
Static
(more information)
0-D
AC Steady-state
Lumped parameters
Switching average
Assemblies
1-D
1-D
2-D
Distributed
parameters
3-D
Switching detail
Computational
Physical Process Resolution
Time resolution
(more information)
(more information)
Static
0-D
AC Steady-state
Lumped parameters
Switching average
PhysicalSwitching
Process detail
Resolution
(more information)
Computational
Time resolution
Static
(more information)
0-D
1-D
AC Steady-state
Lumped parameters
Switching average
Components
Materials
1-D
2-D
Distributed
parameters
2-D
Distributed
parameters
3-D
3-D
Switching detail
Ill Posed:
1-D
2-D
3-D
Distributed
parameters
• A set of technologies
can yield many different systems
• A system can have many different sets of technical solutions
Time resolution
Computational
StaticTime resolution
0-D
AC Steady-state (more information)
Lumped parameters
Switching average
Switching detail
Computational
(more information)
70
Traditional Power Electronics Industry
Advanced Electric
Power Systems Thrust
Advanced Electric
Power Systems Thrust
PEBB Based Power Electronics Industry
71
Advanced Electric
Power Systems Thrust
Advanced Electric
Power Systems Thrust
Asynchronous Processes for Multiplicative Product
Development -- Concurrent Engineering
PEBB -- A Simple Set of Blocks
for Power System Development (Functional)
Thermal
Power Switching
filter
Senses what
they are
plugged into...
• PEBB defined by IEEE
(Power Engineering Society)
• WG I8
• TF2, PEBB Technologies
Senses what is
plugged into
them...
PEBB
I/O
I/O
Makes the electrical
conversion needed via
software programming
(Embedded Agents)
filter
Controls
Functions In Software
Inverter
Breakers
Frequency Converter
Motor Controller
Power Supply
Actuator Controller
Industry Standards Initiated
72
Advanced Electric
Power Systems Thrust
Universal Control Architecture for Control
Interfaces (temporal) , IEEE Guide Initiated
PEBB Concept for Power Electronics
VTB Simulation Environment
Advanced Electric
Power Systems Thrust
Roger Dougal
Mechanical system
Pump
Fluid
Impeller
Motor
Shaft
Rotor
Stator
Real PEBB
systems are
multi-technical
Conduction
Heat
Generation
Heat
Sink
Ambient
Thermal system
73
Thermal system
Motor Controller
Cable
Power
Electronics
Heat sink
to ambient
Cable
Actuator Plumbing
Electrical system
Circuit Breaker
Current
sense
& arc
dynamics
Cable
Hydraulic system
Stator
Armature
Generator
Rotor
Shaft
Engine
Mechanical system
Advanced Electric
Power Systems Thrust
Validation, Emulation, and
Incremental Prototyping
• Validation of models
– Controller In the Loop
– Processor In the Loop
– Hardware In the Loop
• Real-time simulation is needed for real
hardware
• High speed real-time simulation is need for
high-speed controllers
• Multi-rate simulation for distributed simulation
environments
Advanced Electric
Power Systems Thrust
PEBB Examples
ABB Lopak5 IGBT based
PEBB with 12 capacitor DC
bank
Virginia Tech Universal
Controller
ABB ANPC IGCT PEBB
(16 MVA PowerStack)
74
Advanced Electric
Power Systems Thrust
PEBB Applications
ABB Medium Voltage
Propulsion Drive
ABB DVR (Dynamic
Voltage Restorer)Two
units, 22 MVA each
ABB, 40 MW Energy Storage
Applications
Solid State Transfer
Switches and
Current Interrupters
by L-3 Power
Paragon Inc.
American
Superconducto
r PEBB
products
Advanced Electric
Power Systems Thrust
Power Pole 1
PM1000 Developers Kit
Power Pole 2
Power Pole 3
Power Processor
Gate Driver
& Control Interface
Application
Module
Control
Strategy
DSP
A
Pre-charge
Control
Interface
DSP
B
I/O & Communication
Interface
Embedded
Controller
Fiber Optic I/O
Fiber
System
Hardware
Interface
PowerModule
Asynchronous
Serial Terminal
Adapter
Power
Supply
Serial
Port
Connector
75
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
Rapid Product Development Benefits
Advanced Electric
Power Systems Thrust
Gained Advantage ($)
Typical OEM
American
In-house
Superconductor
Development
PM1000
Production
1m
System Integration
1m
.25 m
1m
Iteration
2m
.25 m
S/W Development
3m
.25 m
H/W Development
2m
0
S/W Design
2.5 m
0
H/W Design
1.5 m
0
System Design
1.5 m
1m
Product Dev. Time
14.5 m
2.75 m
Labor & Overhead
$2,175,000
$412,500
Materials
$100,000
$10,000
Testing
$100,000
0
$2,375,000
$422,500
Product Dev. Cost
t=0
2
4
6
8
Months
10
12
PEBB concept leads to a 5 times
reduction in design cost!
Advanced Electric
Power Systems Thrust
Simple APF Hardware Test Bed
Herbert L. Ginn III
1) Power supply, 208V, 60A
2) 6RA70 thyristor control
rectifier (TCR) from
SIEMENS
Supply
iR
uS
iS
uT
iT
u
i
DC Drive
iRh iSh iTh
3) PM1000 PEBB
4) DSP56F807 based
Controller
uR
L
L
PM1000
PEBB
C
L
Motorolla
DSP
based
controller
Shunt Connected Current Controller
76
PC
14
15
Advanced Electric
Power Systems Thrust
Shunt Current Controller Applications
Herbert L. Ginn III
Herbert L. Ginn III
Advanced Electric
Power Systems Thrust
•
Generalization of ShCC Digital Controller
Model in VTB
Updating of the VTB ShCC controller
model is carried out at regular intervals
77
Advanced Electric
Power Systems Thrust
Vehicle Power Problem
p = ε dw
dt
w = energy which is equal to the ceiling
amount of the installed generation
capacity (may increase over time with
technology – fractionally)
p, power requirements are increasing
multiplicatively by 10x to 100x
ε = efficiency
Conditions:
1) Size, weight, cost stay the same or decrease
2) Open architecture, plug and play
Notional Integrated Power System (IPS)
Advanced Electric
Power Systems Thrust
78
Advanced Electric
Power Systems Thrust
Architectural Transformation
Electrical Zone No. 2
Rolls-Royce/
ABB/ESRDC
Eliminate Charging Circuit
Advanced Electric
Power Systems Thrust
CONCEPT
Future Vision of Shipboard Electrical Design
Development Process
MODELING AND
SIMULATION
Prototype Design
Verification &
Validation
CONTRACT
(DETAIL)
PRELIMINARY
Digital Control &
Real-time
Simulation
MODELMODEL-BASED DEVELOPMENT PROCESS
TRAINING
TESTING
SHIP
DELIVERY
MODEL IS THE SPECIFICATION
Moni Islam, Northrop Grumman
79
CONSTRUCTION
Life of the Ship
(Ship Alts. & upgrades)
Advanced Electric
Power Systems Thrust
Needs Continued – Social Structure
•
•
•
•
Modeling Standards
Benchmark Models
Public Library of Models
A body of international volunteer
experts for all of the above
• And …
80
Center for Power Electronics Systems
A National Science Foundation Engineering Research Center
Virginia Tech, University of Wisconsin - Madison, Rensselaer Polytechnic Institute
North Carolina A&T State University, University of Puerto Rico - Mayaguez
Integrated Power Electronics Building Block
Modules, Converters, and Systems
Fred Wang
Virginia Tech, Blacksburg, VA
[email protected]
Advanced Power Electronics Interfaces for DE Workshop
Sacramento, CA, USA
August 24, 2006
Distributed Energy Resources
•
•
•
•
• Solar
• Fuel cells
• Energy storage
Wind
Bio
Microturbines
Others
Power Electronics Interface a Key Enabling Technology
• Lower cost
• Higher reliability
• Better performance
1
August 24, 2006
81
Improving DE Power Electronics Interfaces
• Conventional approach
– components, circuits, control, processes, design
optimization
• Modular building blocks
– high volume, standardization
• Integration
– reliability, performance, manufacturing
• System
– added functionality and values
CPES focus on IPEMs and IPEM building
blocks based systems
2
August 24, 2006
Center for Power Electronics Systems
A National Science Foundation Engineering Research Center
Virginia Tech
Rensselaer
Polytechnic
Institute
University
of Wisconsin
Madison
System
Integration
University
of Puerto Rico
Mayaguez
IPEM
North
Carolina A&T State
University
Over 80 Industry Partners
Only ERC in Power Electronics
VT – the Lead Institution
3
August 24, 2006
82
CPES Research Vision and Objectives
– Power electronics to follow microelectronics –
Moore’s Law Prevails
• Integrated Power Electronics
Modules (Standardized
building blocks)
• Standardization
• Manufacturability
• Reduce labor content
• Volume
production
• Low cost
• Cost reduction
Signal
Processing
IC
Market ($)
1T
1960
1970
1980
1990
2000
Power Processing IPEM
year
4
August 24, 2006
Vision and Focus
Enable dramatic improvements in the performance,
reliability, and cost-effectiveness of energy processing
systems by developing an integrated system approach via
Integrated Power Electronics Modules (IPEMs).
IPEM Concept:
A concept for design of electronic energy processing
systems with improved performance, reliability,
manufacturability, and reduced cost, based on the
integration of a set of building blocks with:
• Integrated functionality,
• Standardized interfaces,
• Suitability for mass production, and
• Application versatility.
5
August 24, 2006
83
Different Approaches to Integration
• Integrated Load Converters:
PM
Machine
Rotor
Motor and
Converter
Integration
– Low-cost, “intelligent motors”
• motor as output filter
– Fast power delivery to microprocessors
Modular
Pole-Drive
Units
Microprocessor
and Converter
Integration
• minimum distance to load
• Power Distribution Converters:
Discrete converter
Integrated converter
Standard-Cell
IPEMs:
• Active IPEM
• Passive IPEM
• EMI Filter IPEM
• Integrated Source Converters?
6
August 24, 2006
CPES Research Thrusts
Engineered
Systems
IPEM-Based
Power Conversion Systems
(IPEM-PCS)
D. Boroyevich, VT
Fundamental
Knowledge
Enabling
Technology
Electro-Magneto-Thermo-Mechanical Integration Technology (EMTMIT)
T. M. Jahns, UW-M
Microprocessor
and Converter
Integration
Advanced
Power
Semiconductors
(APS)
T. P. Chow, RPI
Standard-Cell
Standard-Cell
Passive
Passive and
and Filter
Filter
IPEMs
IPEMs
Standard-Cell
Standard-Cell
Active
Active IPEMs
IPEMs
Integratable
Materials
High-Density
Integration
(IM)
G. Q. Lu, VT
J. D. van Wyk, VT
(HDI)
Motor
Motor and
and
Converter
Converter
Integration
Integration
ThermoMechanical
Integration
(TMI)
E. P. Scott, VT
Control
& Sensor
Integration
(CSI)
R.D.Lorenz, UW-M
7
August 24, 2006
84
Promoting IPEMs
For Different Power Ranges and Applications
10-100 W IPEMs
1-10 kW IPEMs
10 kW - 10 MW IPEMs
IR iPOWIRTM
Semikron IPM
CPES Integrated
EMI Filter
CPES 800 V, 40 A
ZVZCT phase-leg
TI SWIFTTM
Philips PIP20x
1SO MP
1 revi rD
CPES Flip-ChipOn-Flex Phase-Leg
CPES Transmission
Line Filter
CPES Active
IPEM
CPES Passive IPEM
1SO MN
r ello r tnoC
2SO MN
2SO MP
2 revi rD
CPES Monolithic
VRM
IR, Philips, On Semi,
Intersil, Linear Tech,
TI, Renesas, NSC,
Power One, Infineon,
ST, Maxim, Micrel,
Volterra, Primarion,
Fairchild, Analog
August 24, 2006
1.8 kV, 60 A, 3-level
CPES
ZVZCT phase-leg 4.5 kV, 4 kA ETO
ABB, Hitachi, IXYS, Toshiba, Semikron, Fuji,
Infineon, Eupec, Powerex
ONR, DOE, NSWC, Thales, Northrop
Grumman, Rockwell Automation,
General Dynamics, ABB, Bettis, Alstom,
ACI, PEMCO, TVA
CPES industry consortium members or research sponsors
8
Issues for IPEM Building Block Approach
• Basic building blocks
– “A minimum set of building blocks with
integrated functionality, standardized interfaces,
suitability for mass production, and application
versatility.”
• Architecture & Partitioning
– How to build a power system application with
application-independent PE modules?
• Interface Characterization
– What are interface characteristics and
requirements for a selected architecture?
9
August 24, 2006
85
Topologies Based on Totem-pole
Phase-leg Modules
Single-Ended
Half-Bridge
Full-Bridge
Three-Phase
Multi-Phase
Multi-Level
10
August 24, 2006
Integrated Phase-leg PEBB
+ “Plug & Play” Control Architecture
+
PWM
Generator
Optical
Isolation
Fault & Error
Logic
Communication
Control
Gate
Drive
T
Floating
Power
Supplies
Optical
Isolation
Gate
Drive
Snubber
AC
A
V
Snubber
Current &
Temperature
Measurement
_
35 kVA, 800 V, 20 kHz
Serial Communications Link & Control Power Supply
Universal Controller
(Application Manager)
Smart Phase-Leg PEBBs (Hardware Managers)
…
August 24, 2006
125 Mb/s POF Daisy-Chained Serial Bus (PESNet)
86
11
Passives and Filters Need to be Integral
Part of the Converter
Control Module
Filter IPEM
Active
IPEM
Passive
IPEM
Filter IPEM
Thermal Energy
• Active IPEM
Controls the energy flow (switching)
• Control Module
• Passive IPEM
Absorbs high-frequency energy (temporary storage)
Size reduces with increasing switching frequency
• Filter IPEM
Blocks high-frequency energy (size independent of switching frequency)
12
August 24, 2006
1 kVA, 1-AC (90-260 V) to DC (48 V) Isolated
Converter
EMI Filter IPEM
Passive IPEM
Active IPEM
Discrete EMI Filter
Discrete Components
August 24, 2006
87
13
Architecture, Control HW/SW
- Hierarchical System Architecture
Information System
Universal
Controller
& Software
Control
Network
+
+
+
+
–
–
–
–
PEBBs
Power
Converters
Electric Power System
14
August 24, 2006
Modular Converter Systems
• Example: Parallel Converters
PEBB unit
iZ
DC bus
Specifications
• AC voltage:
• DC voltage:
• Power rating:
• Switching freq:
PEBB unit
5 A /d iv
208 V
400 V
20 kW / unit
32 kHz
5 A /d iv
Ia1
Ia1
AC
Currents
Ia2
Ia2
15
August 24, 2006
88
Modeling and Characterization
- Standard cell interface characterization
Electrical
Control Interface
Electro-Magnetic
Interface
Thermal
Control
Reduced amount of
data
Structural
Interface
Mechanical
Hierarchical
knowledge
PEBB
datasheet
Cover wide spectrum
of applications
Modeling
Avoid poor power
capability usage
PEBB based power electronics design for non-experts
Thermal Interface
PEBB modules with standardized interfaces
16
August 24, 2006
Modeling and Simulation
as Partition Evaluation Methodology
• Physics-based modeling
– Takes into account (within and without)
• Energy fields
• Materials
• Assembly
• Enables system-level evaluation
– Terminal models of subsystems
• Power:
v, i
• Control:
u
• Thermal:
θ, p
• Structural (mechanical)
Mechanical Model
Thermal Model
Electrical Model
Power Converter
• Explicit relationships between terminal variables, while
indirectly capturing internal physics
• Hierarchical reduction of modeling detail
17
August 24, 2006
89
PCS with Integrated Functionality
•
With active control and built-in intelligence, power
converters can change the dynamics of the sources
and loads to:
– Reduce system complexity by decoupling the dynamics
(benefits in design & operation)
– Reduce the oversize margin for sources and loads
– Replace/eliminate bulky passive filters
•
Functionalities:
–
–
–
–
–
Power flow control
Power management (continuous)
PQ control, active filtering
Monitoring, diagnosis, and on-line mitigation
Protection
18
August 24, 2006
Subsystem Interaction Example
– models with input & output impedances –
Front-End
Converter
MV
voref
Iomax
250 A
Load 1
Converter
960 V dc bus
with 2% short-circuit impedance
With Intelligent Control
100
100
250 A
+
330 A
30 A
Battery
With large bus capacitor
200
100
1100
900
900
August 24, 2006
Iomax
0
0
0
1100
1100
0.000
300
iL2
1,000 μF
Load 2
Converter
200
200
700
0.000
700
vL2
30 to 330 A
50 A
Const.
Source Current [A]
300
300
vL1
Bus Voltage [V]
Bus
Voltage[V][V]
Bus
Voltage
SourceCurrent
Current [A]
[A]
Source
Power
Management
and Control
iL1
0.050
0.100
0.050Time [s] 0.100
Time [s]
900
700
0.000
0.150
0.150
0.050
Time [s]
0.100
0.150
19
90
Summary
• CPES promotes an integrated system approach via
Integrated Power Electronics Modules (IPEM)
concept to improve performance, reliability, and
cost-effectiveness of power converters
• IPEM building blocks need passive and filter
modules in addition to active modules
• Benefits can be achieved, and researches are
needed at module, converter, and system levels
• There is a strong need for consistent, physicsbased, system architecture analysis and evaluation
methodology
20
August 24, 2006
Acknowledgement
The work and contributions are result of many CPES faculty, students, and staff.
This work was supported primarily by ERC Program of the National
Science Foundation under Award Number ECC-9731677 and by
Office of Naval Research over the years
Many other US government and industrial sponsors of CPES research
are gratefully acknowledged.
21
August 24, 2006
91
Bricks and Buses
Giri Venkataramanan
University of Wisconsin-Madison
[email protected]
Ph: 608-262-4479
24th Aug 2006
California Energy Commission
Sacramento, CA
CEC, 24th Aug 2006
GV -1
Power Electronics Applications
•
•
•
•
Motor drives 1 h.p. – 5000 h.p.
Power supplies 10W – 5 kW (and >)
UPS systems 100W – 100kW
Compact fluorescents 5W – 50W
• Segmented markets
• DG as a new market segment?
CEC, 24th Aug 2006
GV -2
92
Typical schematic
Idc
Vdc
SB1
SA1
SC1
VAp
SA2
VBp
SB2
ILfA
Lf
VCfA
Cf
SC2
ILfB
Lf
VCfB
Cf
Lt
VCp
I LtC
I LfC
Lf
VCfC
Cf
Lt
ILtC
Lt
I LtC
Itiea
I tieb
Itiec
VNf
Tb
TCB
Tc
Zc
TBA
Za
Ta
Zb
ILda I Ldb ILdc
TAC
VanL
VbnL
VcnL
VnL
CEC, 24th Aug 2006
GV -3
State of the art
CEC, 24th Aug 2006
GV -4
93
Power Electronics Assembly
CEC, 24th Aug 2006
GV -5
Restraints
• Barriers to growth
–
–
–
–
–
–
–
–
–
–
High cost
Low reliability
High complexity
Custom design
Long design cycle
High manufacturing cost
Low volume
Custom interfaces
Lack of scalability
Multi-geometric assembly
CEC, 24th Aug 2006
GV -6
94
Desirable scenario
• Standardized input, output, functionality
• ‘Compilable’ cabinets
• Fault tolerant, fail safe capability
• Plug and play
• Geometries for:
Thermal
Electrical & Magnetic
Mechanical & Industrial design
CEC, 24th Aug 2006
GV -7
MCCB Panel Boards (EATON)
CEC, 24th Aug 2006
GV -8
95
Modular servo drives (Rockwell)
CEC, 24th Aug 2006
GV -9
Components
Power Converter Elements
Electrical
Thermal
Control
Structural
Connective
Networks
Source
Load
Electronic Power Converter
CEC, 24th Aug 2006
GV -10
96
Silicon scaling
CEC, 24th Aug 2006
GV -11
Bricks & Buses Concept
Physical Realization
Sensor Bus
Aux Power Bus
Control Bus
Power Switching Brick
Power
Sensor
Brick
Power
Control
Brick
Auxliary
Power
Brick
Throw Bus
Pole Bus
CEC, 24th Aug 2006
GV -12
97
Bricks and Buses Converter
CEC, 24th Aug 2006
GV -13
Bricks and Buses Converter
CEC, 24th Aug 2006
GV -14
98
Bricks and Buses Converter
CEC, 24th Aug 2006
GV -15
Test results
94
Vdc = 250 V
Net Efficiency (%)
93
Vdc = 400 V
92
91
90
89
88
0
20
40
60
80
100
IGBT Duty Ratio (%)
CEC, 24th Aug 2006
GV -16
99
Radiated Coupling
Location
VPK-PK / Area
(mV/cm2)
A
0.413
B
0.263
C
0.620
CEC, 24th Aug 2006
GV -17
Bricks & Buses
• Standardized dimensions – depth and
height
• Incremental scaling of width
• Each brick thermally self managed
• Variable volume
• Proportional scaling of surface area
• Decoupled power bus and signal bus
• Contained interconnect EMI
CEC, 24th Aug 2006
GV -18
100
3 phase ac-dc-ac converter
ACO 1
ACO 2
ACIN 1
ACIN 2
ACIN 3
ACO 3
Control Interface Unit
Control Interface Unit
Control Interface Unit
CEC, 24th Aug 2006
GV -19
Accomplishments to date
• $70k demonstration seed through CERTS DG
Integration (2001-2004)
• Demonstrated a concept prototype
• Adhoc design
• Comparable electrical performance
• Increased power density
• Modular packaging
• Improved manufacturability
CEC, 24th Aug 2006
GV -20
101
Challenges
•
•
•
•
•
•
Electronics – Silicon
Capacitors – Film, Foil
Magnetic elements – Copper, Iron
Cooling – Heat-sink, Cold plates
Auxiliary – Switchgear
Interconnections – Printed circuits,
busbars
• Design, manufacturing, applications
CEC, 24th Aug 2006
GV -21
Magnetics - trends
Copper
Steel
CEC, 24th Aug 2006
GV -22
102
Beyond Si - Cellular design
• Cell definition
– Switch
– Throw capacitance
– Pole magnetics
– Thermal
CEC, 24th Aug 2006
GV -23
Step and repeat process
• Conforming and compatible layers
–
–
–
–
Thermal management
Switching electronics
Reactive elements
Control/communication (soft)
CEC, 24th Aug 2006
GV -24
103
Air-cooled concept designs
CEC, 24th Aug 2006
GV -25
Liquid-cooled concept designs
CEC, 24th Aug 2006
GV -26
104
Bus Centered Assembly
• Electrical and structural interconnection
• Similar to MCCB panel-boards
CEC, 24th Aug 2006
GV -27
Roadmap
How to integrate the
thermal layer, switching
layer, and reactive
component layer together
structurally to allow
electrical and thermal flow,
in a inexpensive process?
Cellular and
Distributed Control
Development
How to ensure that the
different cells perform the
control function as desired?
ACIN 1
ACIN 2
ACIN 3
Manufacturing &
Design Process
Development
Interconnect
Development
Geometric
Scaling
Studies
Control In terfa ce Unit
Control Interface Unit
Control Interfa ce Unit
What should be the aspect ratio
of capacitors, magnetics and
thermal devices so that their
footprints can be compatible
with switching electronics?
ACO 1
ACO 2
ACO 3
CEC, 24th Aug 2006
GV -28
105
Advanced Topologies
for DE Interface
Ned Mohan
University of Minnesota
Distributed Energy Workshop
Sacramento, CA
August 24, 2006
1
Workshop on Renewable Energy for Minnesota
McNamara Alumni Center, University of Minnesota, Minneapolis
Thursday October 12, 2006
Objectives:
• Discuss renewable energy prospects in Minnesota
• Bring renewable energy curriculum into K-12
• Describe the research being conducted in this field in the Department of Electrical and Computer
Engineering (funded by XcelEnergy, National Science Foundation and ONR)
Who should Attend:
Everyone concerned with energy, particularly the technical issues, and its impact on the
environment and society.
Tentative Schedule:
7:30-8:00
Registration, Coffee and Rolls
8:00-8:30
Welcome and Introduction
• Welcoming Remarks: Steven Crouch, Dean – Institute of Technology, U of M
• Workshop Objectives and Agenda: Ned Mohan, ElectE, U of M
• Renewable Energy Development Fund: Michelle Swanson, XcelEnergy
8:30-10:00
Renewable Energy Overview
• A Power Grid for the Hydrogen Economy: Thomas Overbye, Professor, University of Illinois
• Lessons From Norway: Terje Gjengedal, Vice President - STATKRAFT, NORWAY, in charge
of renewable energy projects
• What is Happening in Minnesota?: Michael Bull, Assistant Commissioner, Minnesota
Department of Commerce (invited)
10:00-10:30
Coffee Break
10:30-11:30
Wind Energy
• Present Projects and Potential in Minnesota: John Dunlop, American Wind Energy Association
• Transmission Planning in Minnesota – CapX 2020: Gordon Pietsch, Great River Energy
11:30-12:00
Research in Renewable Energy at the ECE Dept, University of Minnesota
• Results of Research funded by NSF, XcelEnergy and ONR: Ned Mohan, ElectE, U of M
12:00-1:00
Lunch (buffet lunch provided)
1:00-2:00
Hydrogen and Fuel Cells: Making the Connection
• Hydrogen From Wind: Lanny Schmidt, Regents Professor, ChemE, U of M
• Research in Fuel Cells: Brad Palmer, Cummins Power Generation, Fridley, Minnesota
2:00-3:00
Bringing Renewable Energy and Conservation Curriculum into K-12 Courses
• Sustainable Architecture: Virajita Singh and John Carmody, U of M
• Group Discussion led by: Steven Pullar, Woodbury Math and Science Academy, MN and
Michael Maas, Eden Prairie High School, MN
Posters on Display: Research being conducted in this field in the Department of Electrical and Computer
Engineering, funded by XcelEnergy, National Science Foundation and ONR.
106
2
3
Sources of Distributed
Energy
„
„
„
„
Photovoltaic
Fuel Cells
Wind
Micro-Turbines
4
107
An Ultra-Compact High-Efficiency DC-DC SoftSwitching Converter for Photovoltaic and Fuel Cells
(US Patent:6,310,785 University of Minnesota )
i in
TA+
+
TB+
+
Vin
TA−
T1
T2
+
vrect
TB−
−
−
Vo
−
144244
3144244
3
half - bridge portion
phase − modulated
full - bridge portion
• Combination of uncontrolled
half-bridge and phase shifted
full-bridge
• Uses 4 switches with combined
VA ratings identical to PMC
9 ZVS down to no load
9 Reduced magnetics
9 Smaller conduction loss
compared to PMC
9 Better dynamic response
5
Operating principles
i in
Vin
−
+
+
+
TA
Vin
2
Vin
2
− v T1 +
A
T1
TB
v
+ T2 −
−
TA
vA
Lo
B
T2
+
+
vrect
Vo
−
−
TA−
v T1
0
v T2
0
+
v
− bridge
TA+
0
+
TB
−
TB
−
TB
vbridge
0
• all switches switch at 50% duty-ratio
and constant switching frequency
Vo n1
= + D n2
Vin 2
vrect
Vo
0
6
108
Experimental waveforms
vGS
350V
+12V
v DS
vGS
Vin : 350V − 400V
Vo : 36V − 60V
−12V
0
@ 20 A
f sw : 100 kHz
100 ns
−12V
v DS
vrect
vrect
Vo
Vo
vGS
vrect
Vo
−12V
7
S1
S3
S5
T1
1: n 1
*
D1
*
Vo
L2
Vin
vsec *
*
S2
S4
*
*
0
L1
S6
1:n2
T2
I load
Io
←
D2
HPMC with Current Doubler
8
109
A MultiMulti-Port DC/DC Converter
Hariharan Krishnaswami, Ned Mohan, Department of Electrical & Computer Engineering, University of Minnesota
Objective:
The goal of this project is to develop a compact & efficient dc/dc converter that can serve as an interface between 2 or
more energy sources (e.g., Fuel cells, PV array, batteries) and the load. Such a converter is termed a multi-port converter
with each port connected to a source or a load.
Characteristics of the multimulti-port converter:
1.
A single converter interfacing with several energy sources leads to part count reduction.
2.
Power flow can be controlled from different energy sources to load.
3.
Each port of the converter is bidirectional in nature, for example, a battery needs a bidirectional port.
4.
Applications are in hybrid vehicles, pluggable hybrids and residential homes/buildings.
Proposed converter topology
The block diagram shows two
sources Fuel cell and battery
interfacing with a motor drive
inverter. The battery and inverter
ports are bi-directional.
9
A MultiMulti-Port DC/DC Converter
Hariharan Krishnaswami, Ned Mohan, Department of Electrical & Computer Engineering, University of Minnesota
Advantages of proposed converter topology:
1.
The proposed converter circuit is the dual of the existing voltage fed multi-port converter
2.
The source current ripple is reduced due to the inductor at the input.
3.
High step-up of voltage possible due to the inverse topology.
4.
Power flow control is by varying the phase shift between the full bridges as shown in the block diagram.
5.
By appropriately selecting the turns ratio and matching the voltage levels of the sources and the load, Zero Current
Switching (ZCS) can be achieved over a significant range of load and input voltage variations.
Principle of operation:
The equivalent circuit for analysis can be reduced to high frequency square wave current sources I1,I2 & I3 derived from
the input dc currents IFC, IBatt and Iload respectively. The capacitors are reflected to the secondary of the transformers. The
resultant power flow equations between ports 1(Fuel cell), 2(Battery) and 3(Load) are given in eqn.1. The final load voltage
expression after some algebra is also given in eqn. 2.
⎛
⎞
I I
φ
P13 = FC ' O φ13 ⎜⎜ 1 − 13 ⎟⎟
Ts ⎟
⎛ 1
1
1 ⎞
C1
'
⎜
C1 = ⎜ +
+
⎟ C1C3
2⎠
⎝
⎝ C1 C2 C3 ⎠
⎛
⎞
I I
φ
⎛ 1
(1)
1
1 ⎞
P21 = Batt ' FC φ21 ⎜⎜ 1 − 21 ⎟⎟
C2' = ⎜ +
+
⎟ C1C2
C2
⎝ C1 C2 C3 ⎠
⎜ Ts ⎟
2⎠
⎝
⎛ 1
1
1 ⎞
⎛
⎞
C3' = ⎜ +
+
⎟ C2C3
I I
φ
⎝ C1 C2 C3 ⎠
P32 = Batt' O φ32 ⎜⎜ 1 − 32 ⎟⎟
C3
⎜ Ts ⎟
2⎠
⎝
VO =
⎡VFC
⎛
⎛
C2'
φ ⎞ V
φ ⎞⎤
φ23 ⎜ 1 − 23 ⎟ − Batt' φ13 ⎜ 1 − 13 ⎟ ⎥
⎢
Ts 2 ⎠ C1
Ts 2 ⎠ ⎦⎥
⎛
φ12 ⎞ ⎣⎢ C3'
⎝
⎝
φ12 ⎜ 1 −
⎟
⎝ Ts 2 ⎠
110
(2)
10
SiC-Based
Matrix Converters for Open-Ended
AC Drives for Wind Generators and
Micro-Turbines
MC2
MC1
MC ≡ Matrix Converter
Open-Ended
AC Motor
11
Advantages of SiC Devices
-
Closer to an ideal switch
Lower Losses; Higher Efficiency
High Temperature; Compact Design
Press Release 2006
-
110 kVA SiC-based Inverter by Kansai
Electric and CREE
-
50% less conversion losses compared
to Si inverters
12
111
Power Electronic Systems
- Voltage-Link
conv1
conv2
utility
Load
controller
- Current-Link
Figure 1-19 Load-side converter in a voltage-source structure.
AC1
AC2
Figure 1-17 Current-link structure of power electronics interface.
13
- Voltage-Link
conv1
conv2
utility
Load
controller
Figure 1-19 Load-side converter in a voltage-source structure.
Problems with the Storage Capacitor:
1. Weight and cost
2. Reliability
3. Inrush Current at switch-on
4. Additional currents under input unbalance
5. Difficult to integrate motor and the inverter
14
112
Matrix Converters
AC Source
AC Machine
• Direct-Link (no energy storage)
• Ideal with SiC Devices
15
Highly Simplified Control of Matrix
Converters
ONR Grant: N000140510291
ia
va
va
ia
vA
iA
daA
vB
iB
daB
vC
iC
dbA
vb
vc
daC
vA
dcA
daB
dbB
dcB
daC
vB
vC
dbC
dcC
daA + dbA + dcA = 1
vb i
b
daA + dbA
dbA
vc
daA
dbB
daA
dbC
0
ic
dcA
dcB
dcC
qcA
qbA
qaA
16
113
Laboratory Demonstration
-
Novel : Intellectual Property Disclosure
Papers Attached
- IEEE-PESC 2006 and IEEE-APEC 2006
17
Nearly Doubling (1.876) the Drive Output
Conventional Voltage-Link System
V ph , in
+ V ph , m = V ph , in −
+
Vd
−
Vd = VˆLL, in
Vins = VˆLL , in
Open-Ended Machine
Supplied by Two Matrix Converters
V
ph , in
Vph , m = 1.5V ph , in
+
−
MC1
Vins = Vˆph , in
114
MC2
Vins = Vˆph , in
18
Switching of Common Mode Voltages
Results in Bearing Currents
- SiC devices will make this more acute
19
Source: Prof. Gopakumar, IISc
Isolated Inputs with 30 deg phase shift
- Power Capability increases to 186.7%
- Ideal for Wind Electric Systems as shown below
Y −Δ
Vph , in
34.5kV
Vph , in
Vph , m = 1.867Vph , in
Y −Y
MC1
MC2
Vins = Vph , in
20
115
Capability Curves with Common
Mode Voltages Eliminated*
proposed
Tem =1pu
conventional
Vm =1.5 pu
proposed
Vm =1.0 pu
conventional
0
0.5pu
1.0pu
1.5pu
ωm, f
* Extended to 1.867 pu if input voltages at two sides are21
isolated from each other and 30 deg phase shifted
Simultaneous Benefits
Increases available voltage to 150%*
1.
•
•
rated torque up to 150%* of the rated speed
150%* power output capability
Bearing currents are eliminated
Slot insulation reduced by a factor 1.73
Comparable efficiency at the rated power?
Smaller current ripple?
Input power factor is controllable
Elimination of Energy Storage Capacitor
2.
3.
4.
5.
6.
7.
•
Bulky, inrush current, current under unbalance
* 186.7% if isolated inputs and 30 phase shifted
116
22
Flywheel Battery
„
„
„
Stator dia. = 19 in
Length = 42 in
Objectives of Flywheel Battery
‹ Firm up wind resources on a short-term basis
‹ Interface with alternative generation
‹ Voltage support to the transmission grid
Flywheel Battery Components
‹ Wheel – made with lightweight composites
‹ Enclosure – designed to maintain a low
windage loss environment
‹ Magnetic Bearings – used for low rotational
loss
‹ Motor/Generator – charges and discharges the
battery
‹ Power Electronics and Controls – Control the
Motor/Generator and Magnetic Bearings
Flywheel Battery Specifications
‹ Power = 2 MW
‹ Energy = 100 kWhrs
‹ Speed range = 7,500 to 15,000 rpm
‹ High in-out efficiency
‹ Lowest cost possible
23
Synchronous Reluctance Motor/Generator
Ld
Lq
„
„
„
Synchronous reluctance machine
‹ Low cost and no loss at idle
‹ Relatively low rotor loss
‹ High rotor operating temperature of
250 °C (Most important)
Large ratio of Ld to Lq inductance
Axial Laminated small-scale rotor
designed due to high Ld/Lq ratio
‹ Machines tested in back to back setup
‹ Machine able to operate at high speed
‹ Due to thickness hot rolled steel used
for magnetic layers
24
117
Control of a Doubly-Fed Induction Wind Generator
Under Unbalanced Grid Voltage Conditions
stator
grid
DFIG
rotor
DC link
AC
DC
DC
AC
25
Application of Series
Compensation in Wind Power
26
118
Innovative Methods to Triple Efficiencies of
FAN Motors
• Max Efficiency = 30%
• Starting Problem
• Poor Power Factor
• Pulsating Torque
• Low efficient speed
regulator
• Efficiency goes further
down at low speed
Fan 1
Fan 2
Fan 3
(b)
(a)
Present FAN motor
•
•
•
•
•
•
Speed Setting
Input Power (W)
Efficiency
High
118.81
28%
Mid
91.4
26%
Low
67.69
14%
High
56.2
31%
Mid
43.17
26%
Low
35.82
21%
High
51.86
29%
Mid
34.12
18%
Low
25.97
11%
Proposed FAN motor
High Efficiency (close to 90%)
Power factor close to 0.9 (Design dependent)
Can be wound with the available winding technology
for AC machine
Easy to manufacture, small size, ease in winding
(Outer rotor)
Low cost, readily available ferrite magnet as
permanent magnet
Low assembly cost and not a multi-step process
27
SIMULATION RESULT : Outer Rotor Configuration
Torq
RPM
Freq
P_in
P_out
P_loss
VA
P.F.
Effic
CktVs
PwmIndx
AF_ang
(N-M)
(Rpm)
(Hz)
(W)
(W)
(W)
(VA)
(PU)
(PU)
(V)
(PU)
(deg)
0.966
1000
50
108.7
101
7.68
123.2
0.88
0.93
165
1
0
28
119
FEM
RESULTS
Iron Loss density
Material
Flux density
COST ANALYSIS
Volume
required
(PM in cm3)
Cost of
PM ($)
Cost of
Steel ($)
Cu Cost
($)
Size of
machin
e (mm)
Cu Loss
(W)
Iron
Loss
(W)
Total
(Loss,
W)
Total Cost
($)
Neo (NdFeB)
22.12
11.06
2.79
2.39
100
4.36
4.22
8.58
Hybrid (60% Neo,40% Ferrite)
24.63
7.17
3.102
2.99
110
4.86
3.8
8.66
13.26
66.6
2.71
3.34
4.4
122
4.03
3.65
7.68
10.45
Ferrite
16.24
A compromise in efficiency (by 5- 8%) can reduce the total cost of motor by 20-30%, Present
target is to achieve the highest efficiency possible at low cost
** For a fair comparison, analysis is done at almost equal losses
120
29
Integrated Modules
Simplify Systems Design
By: John Mookken
SEMIKRON USA
8/24/06
Advanced Power Electronics DE Workshop
Sacramento, CA
11/2/2006
1
Evolution of the Power Module
11/2/2006
121
2
Why Integrate?
Shorter time to market
Easier system design & assembly
Economical
Reduced number of components
Customized solution without the custom pricing
Standard Interface
Commonality or standard platform
11/2/2006
3
SKAI: Block diagram
CAN
communications
Controller
Power Supply
Protection
Gate Driver
current
voltage
temperature
V
T
I
I
Heat Sink
11/2/2006
122
4
SEMIKUBE
« A 390A rectifier + inverter
into a 400mm cube »(*)
Includes all sensing (current,
voltage, temperature)
(*) actual max dimensions are 412 x 435 x 380
11/2/2006
5
SKAI: Components
Cover
Driver / Controller board
Sealed 14 pin connector
Current sensors
DC Filter Capacitor
DCB /w Si devices
Heat sink
Power terminals
1200/600V IGBT SKAI module
11/2/2006
123
6
AFE / Inverter Example
Aux. power
Communications
Load
feedback
EMI Filter
Line current
& Voltage
Coolant
In
Intelligent
Power
Module
(AFE)
Intelligent
Power
Module
(Inverter)
Load
Coolant
Out
7
11/2/2006
DC/DC Example
Aux. power
Communications
Load
feedback
Coolant
In
Intelligent
Power
Module
(H-bridge)
Intelligent
Power
Module
(Inverter)
Load
Coolant
Out
11/2/2006
124
8
Example Systems
11/2/2006
9
H-Bridge Example
Aux. power
Communications
Coolant
In
Intelligent
Power
Module
(H-bridge half)
Load
Intelligent
Power
Module
(H-bridge half)
Coolant
Out
Dual modules assembled
on motor end bell / heat sink
11/2/2006
125
10
SKAI: Heatsink Options
Liquid
Air
Options available with
LV or HV SKAI modules
Modules can also be assembled
on custom heat sinks on request
Metal Plate
11/2/2006
11
IPM: Solution
SKAI core
Choose Std. SKAI options
Heat sink
Driver/Controller
Current Sensors
Application Specific
SKAI module
Customer adds
Application software
11/2/2006
126
12
www.SEMIKRON.com
Thank you
for your attention
Questions or
Comments ?
John Mookken
[email protected]
11/2/2006
127
13
Distributed Energy
Advanced Power
Electronic Interfaces
Ben Kroposki
National Renewable Energy Laboratory
Distributed Energy (DE) Applications
• Energy Management
Reciprocating Engines
Advanced Turbines
• Electricity to Grid
• Baseload/CHP
Wind
• Peak/Demand Reduction
• Reliability/Backup Power
• Power Quality
• Grid Ancillary Services
Photovoltaics
Fuel Cells
Microturbines
128
DE Grid Interconnection
Distributed Energy
Resources
Interconnection
Technologies
Electric Power
Systems
Utility
Grid
Functions
Fuel Cell
•Power Conversion
PV
Inverter
•Power Conditioning
(PQ)
Utility Grid Simulator
Micro Grids
•Protection
Microturbine
Wind
Loads
•DE and Load Control
Energy
Storage
Local Loads
Load Simulators
•Ancillary Services
•Communications
Switchgear,
Relays, & Controls
•Metering
Generator
Interconnection System Functional Block Diagram
AC Loads
Interconnection System
Power
Conversion
DER
control
Transfer
Switch or
Paralleling
Switchgear
DER
monitoring/
metering
Dispatch
and control
et
er
Local EPS
Protective
Relaying
M
DER
Electric
Generator
P
Co oin
up t o
lin f C
g om
m
on
Power
Distribution
(within dot-dash lines)
DER
(prime
movers,
energy
storage))
DC Loads
Area EPS
Protective
Relaying
Area EPS
Power
System
(grid)
Power Flow
Communications
The interconnection system (within the dotted line) is designed to handle the power between
and serve as the communication and control gateway among the DER, the Area EPS and the
customer loads. Workshops with industry provided a forum for furthering this activity and
several manufacturers are working on developing and validating standardized, advanced,
universal interconnection technologies [NREL/SR-560-32459].
129
PE Applications with DE Systems
PE
PE
PE
DE Power Electronic
Interfaces
Benefits of Power Electronic
Interfaces for DE
• Improved Operating Efficiencies
– Variety of topologies for power electronic
interfaces can improve conversion
efficiencies
– Allow for variable speed operation of
internal combustion engine DG
130
Benefits of Power Electronic
Interfaces for DE
• Power Quality
– Harmonic Control
– Power for Sensitive Loads
140
Areas of Interest
(1)
Percent of rated voltage (%)
120
100
(2)
• Voltage Sag – DE may be
able to help keep voltage up,
but only if allowed to do so.
40
IEEE 1547 (2003) Trip Limits
20
0
0.01
0.1 0.16
0.5
1
2
10
• Voltage Regulation – DE can
provide voltage regulation if
allowed. This can also be a
limiting factor as to penetration
on a feeder.
• Harmonics – There are
harmonic concerns with both
rotating and inverter based
DE.
(3)
ITI (CBEMA) Curve (2000)
80
60
• Sustained Interruptions –
DE can provide backup power
if designed to do so. This may
improve reliability if designed
and operated properly.
100
Time (s)
Benefits of Power Electronic
Interfaces for DE
• VAR Support and Voltage Regulation
Power Factor
Voltage Regulation
+jQ
(lag)
-PDE
w/o DG
QLoad
with DG
S2
S1
Range A
θ1 = 36.8°
θ2 = 52.7°
DG
PLoad
Real Power (W)
131
Benefits of Power Electronic
Interfaces for DE
• Reduced DE Fault Currents
– Ability to recognize dI/dt of fault currents and
clamp or disconnect
– This allows for use of DE on networked systems
and easier integration with protection system
• Interoperability with a variety of other DE
sources
• Standardization and Modularity
– High volume manufacturing techniques
IEEE 1547 Series Standards
1547-2003 Standard for Interconnecting Distributed Resources
with Electric Power Systems
1547.1-2005 Conformance Test Procedures for
Equipment Interconnecting DR with EPS
Current Projects
Future Projects
P1547.2 Application Guide for IEEE 1547
Standard for Interconnecting DR with EPS
DG Specifications
and Performance
P1547.3 Guide for Monitoring, Information
Exchange and Control of DR
Guide for Grid/DG
Impacts Determination
P1547.4 Guide for Design, Operation, and
Integration of DR Island Systems with EPS
P1547.5 Guidelines for Interconnection of
Electric Power Sources Greater Than 10 MVA
to the Power Transmission Grid
P1547.6 Recommended Practice for
Interconnecting DR With EPS Distribution
Secondary Networks
132
Interconnection
System Certification Guide
Power Electronic Interface
Specifications for DR
Covers IEEE 1547
Section 4.3.2
Covers IEEE 1547
Section 4.1.4
IEEE 1547.1 Interconnection Tests have been incorporated
into UL 1741 for product certification
DE Interconnection Equipment Certification Approach
IEEE 1547
Interconnection
System Requirements
•Voltage Regulation
•Grounding
•Disconnects
•Monitoring
•Islanding
IEEE 1547.1
UL 1741
•Interconnection
System Testing
•O/U Voltage
•and Frequency
•Synchronization
•EMI
•Surge Withstand
•DC injection
•Harmonics
•Islanding
•Reconnection
Interconnection
Equipment
•Construction
•Protection against risks
of injury to persons
•Rating, Marking
•Specific DR Tests for
various technologies
NREL DER Test Facility
Microturbines
Synchronous Generators
Utility
Grid
3 AC Buses
Grid
Simulator
Inverters
• Natural Gas
on site
Wind Turbines
3 DC
Buses
Battery
Banks
Load Simulators
• Test
Systems up to
200kW
• All DER
Technologies
PV Array
• Full IEEE
1547.1 testing
Fuel
Cells
Electrolyzer
133
Modular and Scalable Power
Converters in the UPS Industry
Ian Wallace
Eaton Corporation, Innovation Center
1
© 2006 Eaton Corporation. All rights reserved.
Content
ƒ Eaton Overview
ƒ Eaton Electric – UPS Business
ƒ Today’s Critical Power Systems
ƒ UPS Market Drivers
ƒ Modern UPS converter technology
• Design for reliability
• Scalability & Redundant Systems for high 9’s reliability
• Topology and control
ƒ Modularity : Power Control
• Two examples:
• 9390 UPS power / control structure
• Blade UPS modularity / power density.
2
© 2006 Eaton Corporation. All rights reserved.
134
Eaton Overview
Electrical
Fluid Power
Automotive
Truck
•A global diversified industrial manufacturer
ƒ 2005 sales: $11.1 billion
•A leader in:
ƒ Electrical power quality and control
ƒ Fluid power systems
ƒ Automotive engine air management
ƒ Intelligent drivetrain and safety systems for trucks & heavy vehicles
3
© 2006 Eaton Corporation. All rights reserved.
What Markets Does Eaton Serve?
Residential
Industrial Facilities
& Utilities
Commercial/Institutional Facility
Telecom / Data Centers
4
© 2006 Eaton Corporation. All rights reserved.
135
Eaton Business Segment – Electrical
$3.7 billion sales in 2005.
14,000 employees, 57 factories in 19 countries
Æ electrical control, power distribution, UPS,
industrial automation products & services, …
• Power Quality Systems
• Power Component & Systems
• Electrical Components / Industrial Control
5
1893
1979
1994
2003
2004
Founded in
Milwaukee
C-H Acquired
By Eaton
Acquired DCBU
Westinghouse
Acquired the
Electrical Group
Of Delta, plc
Acquired
Powerware
© 2006 Eaton Corporation. All rights reserved.
Eaton Electrical – Power Quality Systems
• Mission Critical UPS systems for highest
power reliability (emergency back-up)
• Single phase & three phase UPS
Modular, transformerless up to 160 kVA
• Industrial & Rack-mount UPS
• Sag Ride-through Power Conditioner
• Active and Passive Harmonic Filters
• Static Transfer Switches
• Advanced Battery Management
• Integration & Global Service Support
6kVA UPS
Rack-mount
750kVA UPS
30kVA
UPS
6
© 2006 Eaton Corporation. All rights reserved.
136
160kVA
UPS
UPS Systems – Key to 24/7 Daily Life
¡
3-phase
3-phase UPS
UPS
Clean
AC
Power
¡
¡
¡
¡
¡
¡
1-phase
1-phase UPS
UPS
Clean
AC
Power
¡
¡
¡
¡
¡
¡
Power Quality
¡
¡
¡
7
Data Centers
Diagnostic Imaging
Broadcast Transmitters
Government Facilities
Industrial Applications
Servers
Networks
Computer Rooms
Clinical lab equip.
Bank ATM
Industrial PLC
Telecom
Wireless
DSL
Central Office
Customer Premise
© 2006 Eaton Corporation. All rights reserved.
Eaton UPS Market Position
• Eaton is an industry leader and globally recognized
provider of innovative, effective power quality solutions,
delivered under the Powerware brand
ƒ Power protection revenue ~ $900M
ƒ #1 in worldwide UPS sales above 5 kVA
ƒ #2 in worldwide UPS sales at and under 5 kVA
ƒ Total volume:
>1.5 million units / year
ƒ 3-Phase volume: ~ 7,000 3-phase units / year
ƒ Large installed base of more than 45,000 3-phase UPSs
worldwide
8
© 2006 Eaton Corporation. All rights reserved.
137
Eaton UPS Market Position
> 200 kVA UPS
1 - 10kVA UPS
Small Data
Centers
Light
Industrial
Servers
POS
General
use
10 – 60kVA UPS
Mid Size
Data
Centers
Industrial
9
% Revenue v.s. KVA
2,500 units
20-50kVA
5-20kVA
50-200kVA
60 - 200 kVA UPS
Large Data
Centers
4,500 units
1-5kVA
> 200kVA
5,000 units
< 1kVA
1.5M units
© 2006 Eaton Corporation. All rights reserved.
Eaton UPS Technology Leadership
1993:
1993: Advanced
Advanced
Battery
Battery Management
Management
to
to extend
extend battery
battery life
life
1962:
1962: First
First AC
AC
Power
Power Inverter
Inverter
1972:
1972: First
First
fault
fault tolerant
tolerant
and
and parallel
parallel
UPS
UPS
1960
1970
1968:
1968: First
First
commercial
commercial
UPS
UPS combining
combining
battery
battery chargers
chargers
and
and inverters
inverters
1976:
1976: First
First
UPS
UPS for
for
emergency
emergency
lighting
lighting HID
HID
lamps
lamps
1986:
1986: First
First UPS
UPS
over
over 100kVA
100kVA for
for
computer
computer room
room
1989:
1989: First
First high
high
frequency
frequency
transformer-less
transformer-less
UPS
UPS
1980
1982:
1982: First
First
UPS
UPS suitable
suitable
for
for computer
computer
rooms
rooms
First
First UPS
UPS
specifically
specifically
designed
designed for
for
office
office
2001:
2001: 3kVA
3kVA
rackmount
rackmount UPS
UPS
increases
increases power
power
density
density by
by 40%
40%
1990
1987:
1987: First
First UPS
UPS
with
with advanced
advanced
PWM
PWM and
and
microprocessor
microprocessor
based
based
diagnostics
diagnostics
© 2006 Eaton Corporation. All rights reserved.
138
2003:
2003: 66 kVA
kVA in
in 3U
3U
for
for high-density
high-density
rack
rack applications
applications
2000
1993:
1993: First
First
UPS
UPS to
to offer
offer
load
load segment
segment
2004:
2004: Modular
Modular
2002:
2002: First
First
transformerless
transformerless
Monitoring
Monitoring in
in
UPS
UPS up
up to
to
excess
excess of
of 225,000
225,000
160
160 kVA
kVA
data
data points
points
1996:
1996: First
First UPS
UPS
with
with wireless
wireless
paralleling
paralleling
122 active patents and 98 applications pending
10
2003:
2003: 2nd
2nd generation
generation
wireless
wireless paralleling
paralleling
2002:
2002: First
First dual
dual
source
source UPS
UPS for
for
rack
mount
rack mount
Today’s Critical Power Systems
• Main elements of Critical Power systems
Measured by 9’s of availability
ƒ Multi-source / storage systems
•
•
•
•
Utility (single / multiple feeds)
DC Batteries
AC Generator
DC Flywheels & ultra capacitors
ƒ UPS – one element in high 9’s system
•
•
•
•
11
System design for redundancy
UPS paralleling for redundancy and capacity
Static UPS bypass
Manual / Maintenance bypass
© 2006 Eaton Corporation. All rights reserved.
Today’s UPS Market Drivers
ƒ Power quality under utility
disturbances
ƒ Flexible architectures for high 9’s
reliability
• Parallel redundancy
• Expandable for capacity
ƒ High system reliability, MTBF
• No single point failure
12
© 2006 Eaton Corporation. All rights reserved.
139
Today’s UPS Market Drivers
ƒ Low installation cost
ƒ Low operating cost - high efficiency
ƒ High power quality utility interface
ƒ High power density
ƒ Serviceability – MTTR
ƒ Multi - power source compatibility
ƒ Global sourcing and manufacturing
ƒ Monitoring, diagnostics &
prognostics
ƒ Revenue Æ ~10% growth / yr
ƒ Price
Æ ~ 4% $ reduction / yr
ƒ Maintenance services
13
© 2006 Eaton Corporation. All rights reserved.
Today’s UPS Technology
ƒ Market drivers are addressed by:
• Design for reliability
• Scalable multi-unit operation for high 9’s architectures
− Elimination of single point failures
− Fault identification and selective trip
• Power module topology and design
• Converter modulation and control techniques
• Modular power and control modules
− Build a scalable product line via modularity
14
© 2006 Eaton Corporation. All rights reserved.
140
Converter Design for Reliability
ƒ HALT: Highly Acceleration Life Test
• Thermal cycling, rapid thermal transitions, load
cycling …
• Identify weakest link via product destruction
ƒ HASS: Highly Accelerated Stress Screen
• Ongoing production screening.
• Verify production units continue meet reliability
objectives
ƒ MTBF targets
• UPS Converter > 60,000 hrs
• Parallel redundant systems > 300,000hrs
15
© 2006 Eaton Corporation. All rights reserved.
System Level Modularity and Scalability
System Level Drivers:
ƒ Key to achieving high 9’s of reliability
• parallel for redundancy
ƒ Parallel for capacity - load expansion
Enablers
• Eliminate single point failure
• power & controls
• Communication less paralleling
Hot SyncTM Technology
• Fault location detection
16
© 2006 Eaton Corporation. All rights reserved.
141
Power Availability for Mission Critical Apps
The power grid typically provides 3 - 9’s, or 99.9% reliability.
This equates to almost 9 hours of downtime per year. ‘High
9’s’ are generally considered to mean 6 - 9’s and above.
9’s
3
4
5
6
7
17
Downtime per Year
99.9%
8 hr, 45 min, 36 sec
99.99%
52 min, 33.6 sec
99.999%
5 min, 15.36 sec
99.9999% 31.5 sec
99.99999% 3.15 sec
© 2006 Eaton Corporation. All rights reserved.
Increasing Availability of Power
Parallel redundant systems offer
substantially increased availability
• Can provide “high 9’s” availability
ƒ The best opportunity to increase availability at the source
• There are two fundamental technical issues to solve
for parallel redundant power systems
ƒ Control and stability of two or more AC power sources being
paralleled
ƒ Elimination of all potential system-level single-point-of-failure
• The resulting performance is depending on design
implementation of:
ƒ Load sharing
ƒ Fault isolation
18
© 2006 Eaton Corporation. All rights reserved.
142
Legacy Systems
Load share and synchronization wiring between modules
Limited to
5x9’s
Synchronization
bus
Load-share
bus
UPS
Module
#2
• Single point of failure
• Fault propagation
• Noise sensitive
• Unreliable cables and
connections
19
UPS
Module
#1
UPS
Module
#3
© 2006 Eaton Corporation. All rights reserved.
Legacy Systems
Master / redundant controllers
Ist Controller
UPS
Module
#1
Limited to
6x9’s
2nd Controller
• Drastically increased system
complexity
• Noise sensitive
• Who is right / who is wrong?
• Unreliable cables and
connections
20
© 2006 Eaton Corporation. All rights reserved.
143
UPS
Module
#2
UPS
Module
#3
Powerware Hot SyncTM
Can provide
7x9’s
“Wireless” paralleling of AC sources
• Reduced system complexity
• No single point of failure
• Modules are identical
UPS
Module
#2
• Modules act as peers
• No Primary / Secondary
relationship
• No “Main Intelligence Module”
required
21
UPS
Module
#1
UPS
Module
#3
© 2006 Eaton Corporation. All rights reserved.
Powerware Hot SyncTM
Hot SyncTM provides automatic load sharing and
selective tripping in a parallel system.
• No control wiring required between modules for current
sharing or selective tripping
• Designed to share load with any power source,
including the utility
• Provides flexibility and scalability
• The UPS can be decentralized into the server
equipment and still operate in parallel with additional
server racks
• Ideal for distributed power system applications
22
© 2006 Eaton Corporation. All rights reserved.
144
Hot Sync Load Share Pictorial
TM
Parallel load share control algorithm constantly
drives the module to carry the least amount of load.
This will drive Module 1 back in Phase with Module 2.
Module Load Level
Module 2 Phase
Module 2
In Phase
Module 1 Actual Load
Module 1
Leading
Phase
Module 2 Min Load
Module 1 Phase
•Eaton developed technology – US patents #5,745,356 &
5,745,355
23
© 2006 Eaton Corporation. All rights reserved.
Hot SyncTM Benefits
• Can provide up to 7x9’s availability
of power
• Ultimate scalability with no
additional controls
• Modules in Parallel:
Mains
Bypass
ƒ are absolute peers
ƒ have absolute autonomy
ƒ use 100% intrinsic components
• Seamless transition from capacity
to redundancy
• Increased serviceability
Load
Direct extension to autonomous operation of grid interface
Scalable DG converters
24
© 2006 Eaton Corporation. All rights reserved.
145
Input Power Quality and Efficiency
• Online UPS: maximum protection from utility disturbances
• Source 3-wire and 4-wire loads.
• Maintain efficiency > 95%
• Manage battery lifetime
Previous Technology
AC Source 2
Bypass
AC Source 1
Loads
=
Low power density
ƒ Input line filters
ƒ Output transformers
25
~
1 Phase
&
3 Phase
Limited battery management
© 2006 Eaton Corporation. All rights reserved.
Input Power Quality & Efficiency
• Active front end IGBT Converters (10-200kVA) improve:
ƒ Power quality, grid and generator interface
• Transformerless Double-Conversion UPS Topology
ƒ Elimination of distribution transformers (4 wire source / loads)
ƒ Novel modulation scheme for 4 leg inverters
ƒ Maximized DC bus utilization to maintain efficiency
ƒ Ultra small filter size: optimization of
magnetic component & switching frequency
Increased power density
26
© 2006 Eaton Corporation. All rights reserved.
146
Battery Management
• Battery Systems
ƒ Advanced Battery Management:
• 3 stage charging technique - doubles battery life
& optimizes battery recharge time.
• Prognostics / Diagnostics- provides up to 60-day
advanced notification of the end of useful battery life.
• ProActive Service – max uptime via 24x7 corrective
maintenance, remote monitoring
Source 2
~
1 Phase
&
3 Phase
=
~
=
27
Loads
=
=
Source 1
Bypass
© 2006 Eaton Corporation. All rights reserved.
Modular Product Approaches
• Motivation
ƒ Build a product line to cover wide power range
ƒ Maintain low cost and high reliability
ƒ Enable N+1 redundancy: high MTBF
ƒ Serviceability - Maintain low MTTR
• Where is the appropriate division and extent of
modularity ?
28
© 2006 Eaton Corporation. All rights reserved.
147
Modular Power Block Approach
Power Module
Loads
=
=
~
=
=
~
=
=
~
~
~
~
Embedded Controller
29
© 2006 Eaton Corporation. All rights reserved.
Rack Mount Modular UPS
• BladeUPS:
ƒ 12-60 kW modular, rack-based N+1 power protection
• Features:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
30
Very compact design, high power density (6U)..
Highest power density on the market
No single points of failure in system
Mounts in any industry standard rack
Each module is autonomous - establishes peer-to-peer
relationship when paralleled.
Hot Sync reliability, redundancy, and scalability
• Scalable from 12kW to 60kW
High Efficiency up to 97%
Features hot-swappable battery modules and electronics
Advanced Battery Management (ABM)
© 2006 Eaton Corporation. All rights reserved.
148
1 Phase
&
3 Phase
Thank You
31
© 2006 Eaton Corporation. All rights reserved.
149
Presentation for:
California Energy Commission
Presenter
Distributed Energy Applications
Leverage High Volume,
Modular Power Converters
Perry Schugart
Advanced Power Electronic Interfaces
for DE Workshop
Director, Power Converter Products
12 years, Power Semiconductors
9 years, Power Electronic Systems
Bachelor of Science, Physics
Sacramento, CA
August 24, 2006
[email protected]
Phone: +1.262.901.6036
Fax:
+1.262.901.0104
2
150
Modular & Configurable High Power Converters
•
•
•
•
Programmable Electronic Building Blocks (PEBB)
Configurable for different power conversion needs
High volume, modular architecture
Rapid product development
3
Integrated Modularity with Power Pole Architecture
Fan
or
Heat sink – Air Cooled
Heat sink – Liquid Cooled
Pole
Thermal
Sensor
Voltage
Sense
IGBT
Power
Gate Driver
Main Filter
+ Bus
Current
Sensor
Output
- Bus
Converter Control & Communication
System
Hardware
Interface
Pre-charge
Control
Interface
Power
Supply
Fiber Optic I/O
4
151
PM1000 – Configurable Power Converter
Power Pole 1
Power Pole 2
Power Pole 3
Power Pole 8
Power Processor
Gate Driver
Power
Supply
& Control Interface
Application
Module
System
Hardware
Interface
Control
Strategy
Pre-charge
Control
Interface
I/O & Communication
Interface
PM1000
DSP1
Active Rectifier
DC-DC
DSP2
AC Voltage Source
Motor Control
Embedded
Controller
Fiber Optic I/O
PowerModule Power Converter
• Analog and digital I/O
• Dual digital signal processors
• Fiber optic communications
• Gate drivers
• Auxiliary power supply
• Cooling
- CAN, asynchronous serial
-
Liquid & air
5
Rapid Product Development
From Concept
to Converter
PM1000
Rapid Product Development
Makes it happen the quickest
6
152
PM1000 Rapid Product Development Benefits
Gained Advantage ($)
Typical OEM
In-house
Development
PM1000
.25 m
Production
1m
System Integration
1m
1m
Iteration
2m
.25 m
S/W Development
3m
.25 m
H/W Development
2m
0
S/W Design
2.5 m
0
H/W Design
1.5 m
0
System Design
1.5 m
1m
Product Dev. Time
14.5 m
2.75 m
t=0
2
4
6
8
Months
10
12
14
∆ = 11.75 m
7
Simplify Power Electronic System Development
PDK
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
SDK
PM1000
Fiber Optic I/O
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
PM1000
Fiber Optic I/O
CSPS (IP)
n=1
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
PM1000
Fiber Optic I/O
CSPS (IP)
n=2
PM1000
Fiber Optic I/O
PowerModule
Asynchronous
Serial Terminal
Adapter
Serial Port
Connector
CAN
Bridge
Ethernet
Connector
8
153
CSPS (IP)
n = 30
CAN
Hub
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
15
PM1000 Product Developer Kit – PDK
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
PM1000
Fiber Optic I/O
PowerModule
Asynchronous
Serial Terminal
Adapter
Serial Port
Connector
9
PM1000 PDK
10
154
PM1000 PDK – Active Rectifier
AC
Source
Precharge
Contactor
AC
Protection
-
L
P3
Phase C
Phase B
DC
Load
PM1000
PowerModule
TM
175
Phase A
3-Phase
+
+
Phase C
Ldamp
-
Phase B
Rdamp
P2
PRCH
Com
Com
PS Gnd
NO
PS
PowerModule
TM
PS
AC Filter
PM1000
175
Coil
AC
or
DC
Phase A
P1
2 1 2 1 2 1 2 1
PM1000
PM1000
J4 J3 J2 J1
Phase A
Phase B
Phase C
PowerModule TM
175
175
J16
TX2
TX1
RX3
RX1
RX2
1 2 3 45 6 7 8 9
TX3
Aux Cont
TX4
C damp
RX4
C
Controller / PC
PowerModule
Asynchronous
Serial Terminal
Adapter
Universal, High Power
Converter - PM1000
11
PM1000 PDK – DC/DC Boost
Precharge
Contactor
-
L
P3
DC
PM1000
PowerModule
TM
C
175
-
P2
PRCH
Com
Com
PS Gnd
NO
PS
PowerModule
TM
Aux Cont
PM1000
175
Coil
P1
2 1 2 1 2 1 2 1
PM1000
PM1000
J4 J3 J2 J1
PowerModule TM
DC +
DC -
175
175
J16
RX3
TX2
TX1
RX1
RX2
1 2 3 45 6 7 8 9
TX3
AC
or
DC
-
TX4
PS
DC
Load
+
+
+
-
+
RX4
DC
Source
Controller / PC
PowerModule
Asynchronous
Serial Terminal
Adapter
Universal, High Power
Converter - PM1000
12
155
PM1000 PDK – DC/DC Buck
Precharge
Contactor
DC
Load
-
L
+
DC
Protection
DC
Source
+
+
P3
PM1000
DC
PowerModule
+
-
TM
C
-
175
-
P2
PRCH
Com
Com
PS Gnd
NO
PS
PowerModule
TM
Aux Cont
Coil
175
PS
AC
or
DC
2 1 2 1 2 1 2 1
PM1000
PM1000
J4 J3 J2 J1
PowerModule TM
TX2
TX1
RX3
RX1
RX2
TX3
175
175
J16
1 2 3 45 6 7 8 9
TX4
DC -
RX4
P1
DC +
PM1000
Controller / PC
PowerModule
Asynchronous
Serial Terminal
Adapter
Universal, High Power
Converter - PM1000
13
PM1000 PDK – AC Voltage Source
Precharge
Contactor
3-Phase
AC Load
-
L
+
DC
Protection
DC
Source
+
Phase C
P3
Phase B
PM1000
DC
PowerModule
+
-
TM
-
175
Phase A
Ldamp
R damp
P2
PRCH
Com
Com
PS Gnd
NO
PS
PowerModule
TM
Aux Cont
Coil
175
PS
AC
or
DC
2 1 2 1 2 1 2 1
PM1000
PM1000
J4 J3 J2 J1
PowerModule TM
175
175
J16
RX3
TX2
TX1
RX1
RX2
1 2 3 45 6 7 8 9
TX3
P1
Phase A
Phase B
Phase C
PM1000
TX4
C damp
RX4
C
Controller / PC
PowerModule
Asynchronous
Serial Terminal
Adapter
Universal, High Power
Converter - PM1000
14
156
PM1000 PDK – Motor Control
Precharge
Contactor
-
3-Phase
AC Motor
DC
Protection
+
DC
Source
+
P3
PM1000
DC
PowerModule
+
-
TM
-
175
P2
PRCH
Com
Com
PS Gnd
NO
PS
PowerModule
TM
P1
Aux Cont
PM1000
Coil
PS
175
AC
or
DC
2 1 2 1 2 1 2 1
PM1000
PM1000
J4 J3 J2 J1
PowerModule TM
TX3
TX2
TX4
TX1
RX3
RX1
RX2
RX4
175
175
J16
1 2 3 45 6 7 8 9
Controller / PC
PowerModule
Asynchronous
Serial Terminal
Adapter
Universal, High Power
Converter - PM1000
15
PM1000 PDK Success Story – Stationary Fuel Cell
Fuel Cell
200 µH
140A
x3
DC
Protection
(DC Source)
Anode
+
-
DC
P3
+
Electrolyte
DC
Cathode
PM1000
300
µF
PowerModule
TM
175
-
P2
750VDC
PRCH
Coil
Coil
Com
Com
PS
PowerModule
TM
PM1000
DC/DC
175
P1
VC1
DC +
J7
VB1
J6
VA1 BAT+ BAT- VC
J5
J4
VB
PowerModule
DC -
J3
VA
DC+ DC-
J2
TM
SHI Board
2 PM1000 PDK’s
PM1000
175
U1 D4 U3 D11
<1 week to demonstrate
125 µH
210A
x3
AC
Protection
480VAC
690VAC
60 Hz
50 Hz
AC
3-Phase
Contactor
Phase C
Phase C
+
-
DC
P3
PM1000
Phase B
PowerModule
TM
175
Phase A
P2
Ldamp
Phase B
Rdamp
Aux Cont
150
µH
PRCH
Coil
Coil
Com
Com
PS
PowerModule
TM
75
µH
Coil
PM1000
175
P1
Phase A
VC1
Phase A
Phase B
Phase C
J7
VB1
J6
VA1 BAT+ BAT- VC
J5
J4
VB
PowerModule
J3
VA
DC+ DC-
TM
U1 D4 U3 D11
16
157
J2
SHI Board
PM1000
175
DC/AC
PM1000 PDK Success Story – Fuel Cell Bus
3 PM1000 PDK’s
DC/DC boost converters
17
PM1000 PDK Success Story – Fuel Cell Bus
Precharge
Contactor
-
L
P3
P2
DC +
DC -
2 1
2 1
2 1 2 1
J4 J3
J2 J1
PRCH
Com
Com
PS Gnd
NO
PS
TM
Cathode
PM1000
175
175
J16
158
RX3
TX2
RX2
T X1
RX1
1 2 34 56 7 89
18
Aux C ont
Coil
175
PM1000
PM1000
PowerModule TM
Anode
Electrolyte
TX3
P1
DC
Protection
175
TX4
PowerModule
+
PM1000
TM
RX4
PowerModule
C
PS
AC
or
DC
PM1000 PDK Success Story – Fuel Cell Bus
Precharge
Contactor
-
L
P3
DC
Protection
175
PRCH
Com
Com
PS Gn d
NO
PS
PowerModule
TM
2 1 2 1
J2 J1
DC -
Aux Cont
Coil
PS
175
AC
or
DC
PM1000
PM1000
PowerModule TM
DC +
PM1000
Cathode
175
175
J1 6
RX3
TX2
RX2
TX1
RX1
123456789
TX4
2 1
J4 J3
RX4
2 1
TX3
P1
Precharge
Contactor
-
L
P3
+
DC
Protection
PowerModule
175
P2
PRCH
Com
Com
PS Gn d
NO
PS
PowerModule
TM
PM1000
Anode
Electrolyte
PM1000
TM
C
Anode
Electrolyte
TM
P2
Regulated
DC bus to
motor drives
+
PM1000
PowerModule
C
Cathode
Aux Cont
Coil
PS
175
AC
or
DC
Fuel cells
P1
2 1
2 1
2 1 2 1
J4 J3
J2 J1
PM1000
PM1000
PowerModule TM
RX3
TX2
RX2
TX1
RX1
TX4
175
175
J1 6
123456789
RX4
DC -
Motor
Drives
TX3
DC +
CAN
Hub
Precharge
Contactor
-
L
P3
PRCH
Com
Com
PS Gn d
NO
PS
PowerModule
TM
DC -
2 1
J4 J3
PM1000
Aux Cont
Coil
175
PS
AC
or
DC
2 1 2 1
PM1000
PM1000
J2 J1
PowerModule TM
175
175
J1 6
RX3
TX2
RX2
TX1
RX1
123456789
TX3
DC +
2 1
Cathode
TX4
P1
Anode
Electrolyte
175
P2
System
Controller
DC
Protection
TM
RX4
CAN
Adapter
+
PM1000
PowerModule
C
19
PM1000 System Developer Kit – SDK
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
CSPS (IP)
PM1000
Fiber Optic I/O
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
PM1000
n=1
Fiber Optic I/O
CSPS (IP)
n=2
PM1000
Fiber Optic I/O
CSPS (IP)
n = 30
CAN
Hub
CAN
Bridge
Ethernet
Connector
20
159
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
PM1000 SDK – Custom S/W & User Programmability
• Series and/or parallel
PM1000
CAN HUB
PM1000s
DSPB with
CSPS (IP)
DSPA
MASTER
• Master DSPA
• DSPB with Customer
System Controller
PM1000
Specific Proprietary
Software (CSPS)
• Laptop with GUI
DSPB with
CSPS (IP)
DSPA
Laptop with GUI
PM1000
- Configure PM1000s
- Monitor
- Download software
DSPB with
CSPS (IP)
DSPA
PM1000
• System level controller with
customer software
DSPB with
CSPS (IP)
DSPA
21
PM1000 SDK – Wind Turbine Application
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
CSPS (IP)
AC Voltage Source
Active Rectifier
PM1000
PM1000
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Ethernet
Connector
CAN
Adapter
22
160
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
CSPS (IP)
PM1000 SDK – Wind Turbine Application
1050VDC
Active Rectifier
AC Voltage Source
PM1000
PM1000
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Ethernet
Connector
CAN
Adapter
23
PM1000 SDK – Wind Turbine Application
1050VDC
Active Rectifier
AC Voltage Source
PM1000
PM1000
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
Active Rectifier
PM1000
D-VAR®
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Ethernet
Connector
CAN
Adapter
24
161
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
CSPS (IP)
PM1000 SDK – Wind Turbine Application
1050VDC
Active Rectifier
AC Voltage Source
PM1000
PM1000
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
Active Rectifier
PM1000
D-VAR®
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Ethernet
Connector
CAN
Adapter
25
PM1000 Wind Turbine & Fuel Cell Application
1050VDC
Active Rectifier
AC Voltage Source
PM1000
PM1000
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
DC-DC
PM1000
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Ethernet
Connector
CAN
Adapter
26
162
Active Rectifier
DC-DC
AC Voltage Source
Motor Control
CSPS (IP)
PM1000 SDK – Fuel Cell UPS Application
750VDC
Active Rectifier
AC Voltage Source
PM1000
PM1000
480VAC
60 Hz
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
Anode
DC-DC
PM1000
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Electrolyte
Cathode
H2
Membrane
CAN
Adapter
Anode
Cathode
System
Controller
Electrolyte
27
PM1000 SDK – Fuel Cell UPS Application
750VDC
Active Rectifier
AC Voltage Source
PM1000
PM1000
480VAC
60 Hz
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
Anode
DC-DC
PM1000
Fiber Optic
Optic I/O
Fiber
I/O
CAN
Hub
Electrolyte
Cathode
H2
Membrane
CAN
Adapter
Anode
Cathode
System
Controller
Electrolyte
28
163
PM1000 SDK – Fuel Cell UPS Application
750VDC
Active Rectifier
AC Voltage Source
PM1000
480VAC
60 Hz
PM1000
480VAC
60 Hz
CSPS (IP)
Fiber Optic
Optic I/O
Fiber
I/O
Fiber Optic
Optic I/O
Fiber
I/O
Air
Heat
Anode
DC-DC
PM1000
Fiber Optic
Optic I/O
Fiber
I/O
Electrolyte
Cathode
Water
CAN
Hub
H2
Membrane
CAN
Adapter
Anode
Cathode
System
Controller
Electrolyte
29
PM1000 2MW Generator Set Application
30
164
PM1000 Distributed Generation Applications
Wind Turbine
PM1000 provides power flow
control of the wind turbine’s
output.
Generator Set
2MW gen-set using a high
speed alternator and
PM1000 for UK Ministry of
Defense naval applications.
Fuel Cell
PM1000 used to provide a
regulated output voltage
from the fuel cell.
31
PM1000 Distributed Generation Applications
Wind Turbine
Fuel Cell
Gen. Set
Wind Turbine
Solar
Microturbine
32
165
PM1000 Distributed Generation Applications
3-Phase AC
Wind Turbine
Solar
Gen. Set
Fuel Cell
33
PM2000
34
166
THE POWER IN
POWER TECHNOLOGY
Modular Inverters
for Distributed Generation
Matthew Zolot
UQM Technologies
Presented at the Advanced Power Electronics
Interfaces for DE Workshop
August 24th, 2006
Outline
THE POWER IN
POWER TECHNOLOGY
¾ UQM Specialization
¾ Functional Specifications
¾ Design for Modularity
¾ System Integration Issues
167
Company Overview
THE POWER IN
POWER TECHNOLOGY
UQM Technologies is a technological leader in the
development and manufacture of very high performance,
power dense and energy efficient:
electric motors
generators
power electronic controllers
for vehicle electrification.
Electrification of Engine-Driven Auxiliaries
¾ Easily adapted, non-disruptive
THE POWER IN
POWER TECHNOLOGY
High Power
Generator
¾ Improved controllability
DC – DC
Converter
¾ Improved reliability
¾ More easily serviced
¾ Flexible architecture
¾ Available export power
Cooling pump
¾ Key strategy to meet diesel
emission mandates
¾ 7-15% improvement in fuel
economy
Cooling fan
Modular HVAC
168
DC – AC
Inverter
Compressed Air
Module
Electric Oil Pump
UQM Core Competencies
THE POWER IN
POWER TECHNOLOGY
Traction system motors
¾ UQM products have technology
advantages over conventional
systems
Competitor
ƒ Power density
– smaller and lighter weight
ƒ Efficiency
– consume less energy
ƒ Performance
– eliminate gearing
– adaptive software control
ƒ Rugged
– automotive & military grade
packaging
Traction system controllers
Competitor
Motor Controller Example
THE POWER IN
POWER TECHNOLOGY
CD40-400L Controller
¾ DC to AC 3-phase motor /
generator controller (4
quadrant)
¾ 140 kW maximum input
(350 VDC, 400 ADC)
¾ 380 x 365 x 120 mm
dimensions
¾ 16 kg weight
UQM’s experience with small,
lightweight vehicle electronics
helped us win this SBIR award
¾ Liquid (water/glycol)
cooled
169
Outline
THE POWER IN
POWER TECHNOLOGY
¾ UQM Specialization
¾ Functional Specifications
¾ Design for Modularity
¾ System Integration Issues
Bringing Unique Perspective to DG
¾ Plug-in varieties of Hybrid
Electric Vehicles are getting a
lot of attention these days.
¾ Automotive requirements for
DG products will differ from
stand-alone implementations.
- High voltage
- High density
THE POWER IN
POWER TECHNOLOGY
UQM DG Inverter Specifications:
¾ Vin: 150 – 360 V
¾ Pout: 250 – 5000W (3 - 1.7kW
modules)
¾ Efficiency: >90%
¾ Galvanic Isolation
- Light weight
- High efficiency
¾ Grid & Stand-alone operation,
50/60 Hz
- Rugged packaging
&
¾ Standards: UL 1741, IEEE
1547, IEEE 519
- Low Cost (key to
automotive)
170
Overall Layout
THE POWER IN
POWER TECHNOLOGY
Aux
Load Terminal
Grid DG
Terminal
=
Caps
FB
Rect
Filt
Filt
Grid DG
Terminal
Aux
Load Terminal
Automated Control Code Generation
Mathworks Autocoding with DSP platforms
¾ Existing and customized MATLAB blocks are
used selectively to quickly develop new systems
¾ Popular Mathworks platform leveraged for
system simulation
¾ Embedded safety features
¾ OEM configurable parameters
¾ Successfully used within
several development programs
171
THE POWER IN
POWER TECHNOLOGY
True Sine Wave AC Generation
THE POWER IN
POWER TECHNOLOGY
Texas Instruments DSP platforms
¾ Enables the use of advanced signal processing
¾ PWM based True Sine wave generation
¾ Software configurable for split-phase, in-phase,
& 3-phase operation
Outline
THE POWER IN
POWER TECHNOLOGY
¾ UQM Specialization
¾ Functional Specifications
¾ Design for Modularity
¾ System Integration Issues
172
Modular Inverter – Design Trade-offs
THE POWER IN
POWER TECHNOLOGY
¾ Higher component integration levels
vs. discrete components on FR4
- Highly dependant on operating
specifications (P, I, V)
- Cost (top priority for Automotive)
- Packaging density
+
=
- Performance (High frequency,
inductance, trace lengths, etc.)
¾ Level of Modularity {PEBB}
- Component Level
- Board Level
- Package Level
Modular Inverter – Initial Design (Base Package)
6 in.
THE POWER IN
POWER TECHNOLOGY
5 in.
8 in.
8 in.
DC-DC module 8x8x8”
Inverter modules 8x8x5” respectively
¾ High frequency, Isolated DC-DC front end: 5kW
- Capable of stand-alone operation
¾ Modular Inverter (up to 3 modules, each 1.7kW)
¾ Liquid Cooled (automotive variety)
173
Modular Inverter – Interconnection Potential
THE POWER IN
POWER TECHNOLOGY
1.67 kW Inverter
5 kW Inverter
10 kW Inverter
¾ Sub-Block Modularity
- 1.7 kW, 3.4 kW, or 5 kW at 120/240 VAC 60 Hz single phase, or 5 kW
3-phase
¾ Block Modularity
- 5 kW, 10 kW, etc… operation
Functional Modularity
THE POWER IN
POWER TECHNOLOGY
120 Split Phase Arrangement
DC/DC
DC/AC DC/AC DC/AC
240 Arrangement
Load
DC/DC
DC/AC DC/AC DC/AC
Load
3φ Δ Arrangement
3φ Y Arrangement
DC/DC
DC/AC DC/AC DC/AC
Load
DC/DC
DC/AC DC/AC DC/AC
Load
Terminals
120∠0° Hot OR 240 Hot
120∠0° & 120∠180° Neutral
120∠180° Hot OR 240 ‘Neutral’
174
Outline
THE POWER IN
POWER TECHNOLOGY
¾ UQM Specialization
¾ Functional Specifications
¾ Design for Modularity
¾ System Integration Issues
Challenges to Going Modular
THE POWER IN
POWER TECHNOLOGY
¾ Goal: prevent redesign/modifications for every unique
implementation
- Enable higher volumes and reduced costs
Challenges:
¾ Evaluate mechanical connections for all types of terminal
requirements (Input & Output)
¾ Communication: between modules & packages
¾ Anti-Islanding: Identification and prevention
¾ New market: will the egg grow into a Chicken?
175
Questions?
THE POWER IN
POWER TECHNOLOGY
176
Power Electronics Conversion for
Distributed Energy Applications
By: Dr. Alex Levran
EVP & CTO, Magnetek Inc
CEC & NREL
www.alternative-energies.com
Overview:
• Technology
• Applications and Products
–
–
–
–
–
Wind
PV
Variable Speed
Energy Storage
Fuel cells
• Future Trends
177
Magnetek Inc - Fast Facts
Headquarters: Los Angeles, CA (USA)
Listed on NYSE, ticker MAG
Sales >$250M
1,500+ Associates worldwide
7 plants in Europe, North America, Asia
Core Technology: Power Electronics Conversion
Embedded products and Systems
Distributed Energy Technologies
• Wind
– Large farms compete with central generation
– Residential applications <10kW
• Photovoltaic
– Growing Commercial and residential applications.
– Lower cost materials and manufacturing processes for PV panels
key to increased market penetration
• Energy Storage
– Full range of batteries, flywheels and ultra-capacitors evolving for
managing transients, compressed air,SMES
• Fuel Cells
– Automotive applications key to small-scale FC economics
– Limited success in commercial and telecom
• Variable Speed Generation
• Microturbines
– Lower cost, higher reliability critical for market expansion
178
Power Electronic Conversion Requirements
• Grid Connection
– Anti Islanding, kVAR control, Unbalance/Nonlinear Loads
– Low and medium voltages
– Power Quality and Harmonic Distortion (IEEE 519)
– IEEE 1547 Standard for Interconnecting Distributed
Resources with EPS.
– DC current injection (w/o transformer)
• Higher Efficiencies
– Power Conversion
– Energy Harvesting
• Mechanical Packaging
– Parallelable, scalable designs
– Indoor and outdoor applications
– Thermal management : air and liquid cooling
– Compact designs, higher power densities
• Improved Reliability
• Cost competitiveness
• Communication and Remote Monitoring
– Power Line and/or RF Communication
– SCADA and GIS interfaces
Power Electronic Inverters Technology
• Converters/Inverters Topology:
– Voltage source for stand alone. Current Source for grid
connected operation
– Sinusoidal PWM,multi(three) level or space vector
modulation.
– Low or high frequency galvanic isolation
– Non-controlled and active rectifiers. Buck /Boost
Converters.
– Unidirectional and bidirectional architectures/operations.
– System integration configurations: cascade inverters,
cascade rectifiers, cascade total conversion systems
• Control Circuits and Algorithms (digital):
–
–
–
–
Voltage, Current and Frequency Control
Power Flow Control
Real and Reactive Power Sharing
Protection Circuits
• Local and Remote Communication Protocols
(supervision, controls, and monitoring)
179
Strategy: To lead the market of power electronic
interfaces for alternative energy systems.
• High reliability and efficiency
power converters
• Primary energy source control
• Grid interface know-how (grid
tied, stand alone, hybrid)
• High power density and
compact size
Photovoltaic
Systems
• System level control
• Modular design for multiple
sources (PV, wind,FC).
Wind
Generators
• Scalable design. common
building blocks & platforms
Fuel Cell
Systems
Microturbines
and Variable
Speed
Distributed
Generation
Wind Power Conversion
COMPLETE POWER INTERFACE FOR SMALL POWER
WIND SYSTEMS
• Up to 10kW
• Most compact design available on the market
• Stand Alone and Grid-tied operating modes
• Optional Photovoltaic and Genset inputs
• Split phase inverter for worldwide 110V/60Hz or
220V/50Hz operation
• Aurora PV platform with minor change.
• Parallelable.
• Advanced communication
POWER CONVERTER FOR LARGE POWER
WIND SYSTEMS
• Up to 3.0 MW
• DSP based digital control
• Parallel multiple 625 kW inverters
180
Small Power Wind Inverter Topology
G r id In te r a c t iv e In v e r t e r S y s t e m f o r S m a ll W in d T u r b in e
E le c tr ic a l a n d C o n t r o l B lo c k D ia g r a m
A u ro r a W in d In v e r te r
20 A
A u r o r a W in d
In te fa c e B o x
D C /D C B o o s t C o n v e r te r
H i g h V o lt a g e D C B u s
CB1
G r id In te r fa c e In v e rte r
K1
PMSG
L in e F ilte r
PM G
in p u t
V oc = 4 0 0 V m a x.
V n om = 3 6 0 V n o m .
V m in = 4 0
20 A
To
D is tr ib u tio n
P a n e lb o a r d
B re a k e r
3 .6 k W
3 .6 k W
G a te D riv e B o a r d
G a t e D r iv e B o a r d
O p to is o la tio n
Lo ad Ba nk
( O p t io n a l )
D C C u rre n t F e e d b a c k
G e n e r a t o r V o l ta g e F e e d b a c k
I n v e rt e r
E m In
b evdedr te
e dr
d dre d
CEom
n trb oelle
C o n tr o lle r
In v e rte r C u rre n t F e e d b a ck
G r i d V o lt a g e F e e d b a c k
O p e ra to r
In te rfa c e
2 - lin e L C D
R eset
Large Power Wind Turbine Inverter
•
Typical Characteristics:
– Output Voltages: Low to medium
– Grid Connection: UL1741 or Stand Alone
-
•
Topology:
–
–
–
–
•
Indoor and outdoor designs. Air and water cooled designs.
Full bridge rectifier
Voltage fed three phase inverter with adjusted current
Three Level Inverter or Space Vector Modulation
Bi-directional conversion for doubly fed generators.
Features:
–
–
–
–
–
–
–
High efficiency (>97%)
Low THD meets IEEE 519
Modular and scalable designs
Enhanced voltage regulation
Compact design
Advanced communication
Closed loop controls with the turbine
181
Large Power Wind Turbine Inverter
G r id In te r a c tiv e V S C fo r W in d tu rb in e
E le c tric a l a n d C o n tro l B lo c k D ia g r a m
D C C hoke
(G e n e ra to r D e p e n d a n t)
1400 V D C Bus
G rid In te rfa c e In v e rte r
G e n e ra to r R e c tifie r
2 32 0 A
K2
L in e
F ilte r
PMG
K1
CB1
T o 6 9 0 V A C G rid
3 -w ire O u tp u t
2 .5 M W
G a te D riv e B o a rd
F ib e r O p tic
G e n e ra to r C u rre n t F e e d b a ck
G e n e ra to r V o lta g e /F re q u e n c y F e e d b a c k
PCU
E m b ePdCdUe d
b elle
d dre d
CEom
n tro
C o n tro lle r
In v e rte r C u rre n t F e e d b a ck
G rid V o lta g e F e e d b a c k
F ib e r
TCU
C o n tro lle r
N o te s :
1 . D a s h e d lin e s in d ic a te c u s to m e r s u p p lie d w ir in g .
2 . P M s y n c h ro n o u s g e n e ra to r b y C u s to m e r.
3 . D e n o te s d e m a rc a tio n b e tw e e n c u s t o m e r -s u p p lie d a n d fa c to ry -in s ta lle d w irin g .
Three Phase Bridge VSC Topology
720-800V
BULK
VOLTAGE
EMI
filter
EMIFILTER
PMG
FUSE
0
IGBT
BREAKING
AUX
POWER
DRIVING BOARD
DESAT IGBT
OPTICAL FIBER
OPTICAL FIBER
GROUND FAULT SENSING
DSP BOARD CONTROL
AND ANTI-ISLANDING)
AUX POWER
SUPPLY
OUTPUT INTERFACE
AND IEEE485
UTILITY GRID
182
Three Phase Tri-level Inverter
Three Level Inverter
filter
capacitors
three level
inverter
High
speed
generator
three level
inverter
three level
inverter
4.2KV 60Hz to
isolating
transformer
Large Power Wind Turbine Inverter(>2.5MW)
183
Advantages of Large Wind PMG Turbine- Up to 5.0 MW
Variable Speed Converter (VSC) Value Proposition
Advantages of Full Scale Conversion with PMG (Permanent Magnet Generator):
Increase efficiency of 7 1/2% over wound rotor technology for
variable speed:
•
•
•
•
•
•
•
PMG Generator 3% more efficient than the Wound rotor
induction generator
PMG
is 1/3 the size and cost
.
Gear box 1/2 the size and cost, while 2% more efficient
Converter is 2 1/2 % more efficient and 1.5 x cost
Wound rotor systems in the 2 MW range are $.047 kWh vs.
$.032 kWh with Full conversion utilizing PMG
Avoids infringements of current IP
No brushes as with wound rotor generators for higher reliability
.
Photovoltaic Power Conversion
AURORA
PHOTOVOLTAIC
INVERTERS
• Up to 6000W
• Top level performance
• Indoor and Outdoor
models
• Advanced remote
communications
184
Residential Photovoltaic Inverters
• Topology:
– Single or multi-string conversion
– Typical Architectures:
• Boost converters with DC link and PWM full bridge inverter with or without low
frequency transformer isolation (grounded PV panels)
• Single inversion stage with low frequency transformer for galvanic isolation and
voltage adjustment.
• Typical Performance:
–
–
–
–
–
–
–
Power Ratings: 500W to 8000W
Wide open circuit voltage range from 90VDC to 600VDC
High efficiency: Exceeding 96%
Cost competitive, high power density design
Harmonics: meets IEEE 519 spec
Grid connected operation: Meets UL 1741 and VDE requirements.
High overload capabilities, operates at high temperatures, and anti-islanding
protection
– Packaging: Indoor meets Nema2(IP21) and outdoor meets Nema4(IP65)
– Advanced local and remote communications and continuous data logger
Optimal Performance
Aurora higher power models are Multistring inverters with two
independent and fast Maximum Power Point Tracking (MPPT) inputs
+
Booster 1
EMI
and
protections
+
Booster 2
-
PV Array
Voc = 600 V max.
Vnom = 340 V nom.
Vmin = 150 Vmin.
Booster DSP control
185
Commercial PV Inverter
Commercial Photovoltaic Inverters
• Topology:
– Full Bridge with PWM or multilevel controls and topologies.
– Parallel-able with advanced master/slave assignment algorithm
• Typical Performance:
–
–
–
–
–
–
–
–
Power Ratings: 30kW to 250kW. 50kW modules
Wide open circuit voltage range from 300VDC to 600VDC or 400VDC to 900VDC
High efficiency: Exceeding 97%
Advanced MPPT algorithm to harvest higher energy
Cost competitive, high power density design
Harmonics: meets IEEE 519 spec. Low DC current components.
Grid connected operation: Meets UL 1741 and VDE requirements.
High overload capabilities, operates at high temperatures, and anti-islanding
protection
– Packaging: Indoor meets Nema2(IP21) and outdoor meets Nema4(IP65)
– Advanced local and remote communications and continuous data logger
– Output transformer section (low frequency, low and medium voltages)
186
Multimode Wind Converters
•
Typical Characteristics:
– Multi mode operation: Grid Connected, Stand-alone, UPS
– Universal Inverter: Single phase 230VAC, 110VAC, 50Hz and 60Hz
– Multi Source: Wind, PV (max 420VDC), Gen-sets (115VAC split phase
230VAC, 10%), batteries (48V/110A or 110V/50A).
•
Topology:
– Two stage conversion: DC/DC converter and single phase full bridge
inverter.
•
Typical Performance:
– Power Ratings: 2500W to 6000W
– High efficiency: Exceeding 90% from renewable source and 92% from
Battery.
– Cost competitive compact design
– Harmonics: meets IEEEE 519 spec
– Grid connected operation: Meets UL 1741 requirements
– Advanced local and remote communications
Stand-Alone Single Phase Converter
187
Microturbine - Compact Power Generator
•50kW and 100kW
• Easily Transportable (light and small)
• High Reliability
• High Power Quality
• Reduced emissions
• Cogeneration
• Versatile
Fuel Cell Inverters
COMPLETE POWER INTERFACE FOR FUEL
CELL SYSTEMS – RESIDENTIAL AND
AUTOMOTIVE APPLICATIONS
•PCS – 2000W to 7400W
• Stand Alone and Grid-tied operation
• Auxiliary output for start-up phase of fuel cell stack
• Split phase inverter for worldwide 110V/60Hz or
220V/50Hz operation
COMPLETE POWER INTERFACE FOR
FUEL CELL SYSTEMS – INDUSTRIAL
APPLICATIONS
• PCS-3: 300 kW
• Grid tied and stand alone operating
modes
• MULS (Multiple unit load sharing) up to
six units
• Seamless transition with optional static
switch
188
Fuel Cell Inverter Technology
•
Typical Characteristics:
– Convert DC output voltage from fuel cell module to three phase AC voltage.
– Supports different fuel cell source technologies: Phosphoric Acid, Proton
Exchange Membrane, Molten Carbonate, and Solid Oxide.
•
Topology:
– Two stage conversion. Three phase inverter PWM inverter.
– Space vector modulation or sinusoidal PWM
•
Features:
–
–
–
–
–
–
–
Indoor or outdoor designs.
Water cooled or air cooled
Efficiency over 93%
Harmonics: meets IEEE 519
Parallelable, scalable designs
Connection: stand-alone or grid connected UL 1741
Remote monitoring an control
Large Scale Fuel Cell Inverters >
200kW
• UTC Fuel Cells:
200 kW, (160)
• Installed base exceeds 32 MW
• Other customers: 300kW modules
189
Power Conversion
for Fuel Cells
Energy Storage Converters
• Applications:
– Load Leveling
– Power Quality and Energy Management
– Integration with renewable energy sources for enhanced efficiency
and higher capacity
• Sources:
– Batteries: Lead Acid, Sodium Sulphur-NAS, Nickel Cadmium(NiCd), Nickel Metal Hydride(Ni-MH), Vanadium Redox (VRB),
Lithium Ion(Li-Ion)
– Flywheels,Compressed air storage
– Superconductive Energy Storage
• Typical Topology:
– Bi-directional Two stage conversion: Back/Boost DC Converters
and PWM Inverters with transformer isolation.
• Performance Features and Controls:
–
–
–
–
Power range: 200kW to 10MW
Charging/discharging control algorithms to extend battery life
High efficiency
Low harmonic distortion
Energy Storage Converters
PCS Remote
Controller
&
Comm. Unit
190
Future Trends (>3years)
• Inverter Technology:
– New Topologies (tri-level inverters) and improved control
algorithms.
– Higher voltage and current rating of IGBTs, and SiC components.
– Improved thermal management devices (heat-sinks,
– Improved driver and sensing circuits(fiber optical)
– Improved capacitors and magnetic devices
– Will drive:
• Higher conversion efficiency, higher power density, higher reliability
• Higher voltage (Medium), higher power, lower cost
• Expansion of Modular designs:
– Flexibility of installation and application
– Scalability
– Multiple sources of energy, similar platforms (Topologies)
• Improved Communication:
– Enhanced maintenance and service
• Hybrid Systems:
– Combination of PV and Wind with advanced energy storage devices
for better power quality and back-up power applications
191
Xantrex Power Electronics for
Renewable Energy System Applications
Ray Hudson
Vice President Advanced Technology
[email protected]
Outline
• Xantrex Overview
• Renewable Energy Power Electronic Converter
Products
• Residential Solar – Grid Tied
• Residential Solar – Off-Grid/Backup
• Industrial/Commercial Solar – Grid Tied
• Wind
• Others
• Future Direction
2
192
Xantrex Overview
Offices
Livermore, CA, San Luis Obispo, CA, Burnaby BC,
Arlington WA, Elkhart IN, Barcelona Spain,
Reading England, Beijing China
Manufacturing
Livermore CA, Burnaby BC, Arlington WA,
Dominican Republic, China (4 Outsourced
Locations)
Employees
500
Revenue
US$143 Million in 2005
Patents
79 patents with 97 more in progress
Ownership
Public, Traded on Toronto Stock Exchange (XTX)
Established
1983
3
ADVANCED POWER ELECTRONICS Target Markets
Renewable Power
Portable & Mobile
Power
Programmable Power
4
193
Mobile Power
Mobile Power – Product Portfolio
Recreational Vehicles
RS2000/MS2000
Inverter/Chargers
Commercial Vehicles
Portable Power
XPower
Powerpack 150
XPower
Powerpack 400
Railmount
Inverter/Charger
XPower Powerpack 300
Prosine
Inverters & Inverter/Chargers
Micro Inverters
Fleetpower
Inverter/Chargers
XPower Plus Inverters
Freedom Marine 458
Inverter/Chargers
XPower Chargers
TrueCharge
Chargers
Xantrex Battery
Chargers
Prosine
Inverters & Inverter/Chargers
XPower Jumpchargers
5
Programmable Power
Programmable Power – Product Portfolio
Design & Development
XFR 1.2 – 2.8kW
Full Rack Programmable
DC Power Supply
XDC 6-12kW
Digitally Controlled Programmable
DC Power Supply
Value Line (XDL, XPF, XPL, XPH)
Digitally Controlled Programmable
DC Power Supply
Manufacturing Test
XFR 1.2 – 2.8kW
Full Rack Programmable DC
Power Supply
XHR
Half Rack Programmable
DC Power Supply
XPD
Quarter rack Programmable
DC Power Supply
Precision Equipment
XDC 6 – 12kW
Digitally Controlled Programmable
DC Power Supply
XMP
Multiple Output Programmable
DC Power Supply
XT
Quarter rack Programmable
DC Power Supply
6
194
Renewable Power Examples
Solar
Backup
Wind
SW Plus
Off-Grid Inverter/Charger
PV Series
10 kW to 225 kW
NA 3 Phase
Commercial Grid Tie
GT Series
Residential
Grid-tie Inverter
SW Power panel
Off-Grid Backup Power
Inverter Charger
1.5 MW Converter
Industrial Wind
SW Plus
Off-Grid Backup Power
Inverter Charger
GT100E
Int’l 3 Phase
Commercial Grid Tie
GT500E
Int’l 3 Phase Commercial Grid Tie
10 kW Grid Tech Inverter
Small Scale Wind
DR
Inverter/Charger
7
Power Electronics for Solar Applications
• Convert DC from PV Array to AC
• Grid Connected Inverters
• Only source power to utility grid
• Off Grid/Backup Inverters
• Include storage for operation when grid not
available
• Charge Controllers for battery interfacing
• Often included in “Balance of System”
• Is a very key system component
• User interface
• Implements safety features
• “Heart and Brain” of the system
• Sometimes viewed as system weak link
8
195
Solar Portfolio
Battery Based Inverters
Single Phase Grid Tie
3-Phase Grid Tie
GT Series
Residential
Grid-tie Inverter
2.5 to 3.8 kW
PV Series
10 kW to 225 kW
NA 3 Phase
Commercial Grid Tie
DR Series
SW Plus Series
SW Series
9
GT3 Series Residential
Grid Tied Inverter Features
• True 2.5kW, 3kW, 3.6kW power
rating
• High efficiency (CEC 94.5%)
• Wide PV DC MPPT range
• Faster and less expensive to install
•
•
•
•
Light weight and compact
Integrated DC/AC disconnect
Wiring box
Split chassis design (easy to service)
• Communications:
• LCD display
• Communication ports and software
• Attractive industrial design
• Passive cooling
• Demonstrated reliability
10
196
GT 3 Design Topology
• High frequency design
• Reduces copper losses
• Smaller, lighter magnetic components = compact/low
weight
• Uses new, state-of-art power devices
• Takes advantage of newer/more advanced
semiconductors
11
SW Series
• Off Grid / Primary Power
• Backup Power
• Sell PV power back to utility
/ provide backup power
• Battery charger standard
• Sine wave output power
• Low frequency design
topology
• 2.5, 4.0 & 5.5 kW 120 VAC
60 Hz
• 3.0 & 4.5 kW 230 VAC 50
Hz
• Most features of any
inverter in the world –
complex, but many variable
programming options
• Over 30,000 sold worldwide
12
197
DR Series
•
•
•
•
•
•
•
•
•
•
Off Grid / Primary Power
Backup Power
Battery charger standard
Modified sine wave output
power
Low frequency design
topology
1.5, 2.4, 3.6kW 120 VAC 60
Hz
1.5, 2.4 230 VAC 50 Hz
12 & 24 Volt
High Surge Capacity
Simple to install and use
13
C Series Charge Controllers
• Interface between DC and
battery for charging
• 12, 35, 40, or 60 amps
• Solid state, electronically
controlled, pulse width
modulated (PWM) controllers
• Stand-alone lighting system
controller (C12)
• Charge and diversion
controllers (C35, C40, and
C60)
• Optional temperature
compensation
• Adjustable charge control set
points
• Rugged & reliable
14
198
PV Series Product Overview
•
•
•
•
Three-phase grid connect PV inverter for
commercial, industrial and utility scale
applications
Three product platforms comprising 10
distinct models
Single Stage DC to AC Inversion
Single, “central” inverter minimizes
installation and maintenance costs in large
commercial applications
15
Real-World Installations
PV150 (34) 5.1MW - Tucson Electric Power
99.92% Inverter Availability in 2005
16
199
Key Requirements
Xantrex
High efficiency
Sealed design
Communication capabilities
• Maximizes rebates and minimizes PV
• No external contaminants, no filters to clean,
higher reliability
• Flexible options including free GUI to maximize
uptime
Low part count
• Better reliability and maintainability
Low weight
• Easier to transport and install
AC Disconnect on transformer output
and soft start circuit
• Reduce tare loss and transformer inrush
Wide MPPT Voltage Range
• Covers all temperature conditions and module
types
Negative & Positive Ground Arrays
• Allows use with positive ground modules
FCC Part B compliant
• Less potential interference with communication,
radio, and consumer electronics
Meets all applicable codes including
UL1741 and IEEE 1547
• Inverters can be installed in any jurisdiction
9
9
9
9
9
9
9
9
9
9
17
Power Electronics for Wind Applications
• Convert variable frequency and Voltage AC
from generator to grid compitible AC
• Commercial scale – MW
• Typically installed in North America in large
“windplants” – similarities to central generation
• Ride-Through – FERC requirements
• Communications – utility SCADA
• Small Wind <30KW
• Residential
• Systems sometimes incorporate storage for offgrid or backup applications
18
200
Xantrex Converter Technology
For Induction Generator
Utility
(480/690 V)
Induction
DC
Generator
Line
Filter
G
Utility Inverter
Generator Inverter
Variable Voltage
And Frequency
Generator Control
Line Current Control
19
Xantrex Wind Converter Products
410kW Windturbine
and Converter
33 Meter Blade
Diameter
20
201
Xantrex Wind Converter Products
750kW Windturbine
and Converter
50 Meter Blade
Diameter
21
Xantrex Wind Converter Products
1.5MW Windturbines
and Converter
70 Meter Blade
Diameter
22
202
Xantrex Wind Converter Products
2.5MW Windturbine
and Converter
93 Meter Blade
Diameter
23
Power Electronics for Other DER
Applications
• Xantrex has Experience with Power Electronics
for other Distributed Energy Resource
Applications
• Fuel Cells
• Microturbines
• Advanced Energy Storage
• Flow Batteries
• Superconducting Magnetic Energy Storage
• Fly Wheels
• Large Hybrid Systems
• Relatively small volumes
• Xantrex approach is to leverage from wind
and solar
24
203
Xantrex R&D
• Internal development activities
• Wind is OEM product designed for each turbine
• Advanced solar products
• Other DER applications based on practical business
case
• Sandia High Reliability Inverter Program
• Residential Solar inverter incorporating storage
• NREL PV Manufacturing R&D Program
• 500kW Solar Grid Interactive product
• We support DOE Systems Driven Approach and
Solar America Initiative goals
• Goal of reducing cost of energy ($/kWhr) is key!
25
Future DER Power Electronics Direction
•Optimal SYSTEM design
•Including “Balance of Systems”
components
•Higher Performance Systems
•
•
•
•
•
Higher Reliability
Higher Efficiency
Longer Life
Lower Levelized Cost of Energy (LCOE)
Easier Installation
•CEC leading in setting high expectations for
system performance requirements
26
204
Future Direction
• Support for Higher Penetration Levels
• Wind must meet FERC interconnect standards
• Wind – Ride Through and Grid Support (VARS)
• Solar UL 1741 and IEEE 1547
• Solar – Anti-Islanding and Unity Power Factor
• Likely to come together
• Other DG sources will follow – eventually
• Possibility to move to “Feed-In Tariff” incentive
model in US more broadly
• Maximize Energy Delivered (kWHrs)
• Incentive to optimize all system elements
27
Thank You!
28
205
Power Electronics for DER & Renewable Applications
Northern Power Systems
CEC DE Workshop
August 24, 2006
Northern Power Systems
•
•
•
•
•
Subsidiary of Distributed Energy Systems (DESC)
High reliability power systems, products, and services
225 employees
HQ and manufacturing facilities in Vermont
Regional domestic and international offices for sales
and service
2
206
© 2006
Northern Power Business Segments
• Distributed Generation
• Commercial
• Industrial
• Remote power systems
• Oil & Gas
• Industrial infrastructure
• Village Power
• Renewable power systems
• Wind
• PV
• Biofuels
3
© 2006
Northern EPC Approach
4
207
© 2006
Power Electronics for DER Applications
Drivers for increased PE use
• New DER technologies require PE interface
• DC, variable speed, non 50/60Hz generation and storage
devices
• Use of advanced PE enables additional features and
value across applications
•
•
•
•
•
Standardized interface for simpler interconnect approval
Advanced power system architectures
Utility distribution system support
Increased DER ancillary support capabilities
Increased DER penetration levels on distribution system
5
© 2006
Northern’s Power Electronics Focus
• Flexible power converter platform for multiple markets
• MW Wind
• DER generation and storage assets
• Utility support
• Control capabilities to enable advanced architectures
• PowerRouter® control system
• Family of products to support advanced power systems
• Fast DER switch for critical load support and microgrid
applications
• Site and fleet level energy management systems
6
208
© 2006
FlexPhase™ Power Converter Platform
Developed for wind and DER markets
•
•
•
•
•
Modular converter system for 500kW to
multi-MW applications
Liquid and air cooled versions
480Vac, 690Vac versions
Rack-in power modules
Configurable power modules
• DC-AC, AC-DC, DC-DC,
• uni- or bi-directional power
7
© 2006
FlexPhase™ Power Module Features
• Bi-directional DC-AC or DC to DC power
conversion
• Small footprint & high power density:
2.2 kVA/kg (1,956 kVA/m3) liquid cooled
• Flexible universal control architecture
• Include filtering and magnetics
• EMI controlled at module level
• Internal sensing with built in calibration
• Install and extract like draw-out circuit
breakers
• Low mean time to repair
8
209
© 2006
FlexPhase™ Converter Platform Applications
9
© 2006
FlexPhase™ Platform Features & Benefits
•
Modularity
•
•
•
•
Configurable for multiple applications and power ranges
Exchangeable modules for easy service and support
Low Mean Time To Repair
High performance
•
Full grid support capabilities
•
•
•
Very low harmonics (<1%THD capability)
Reduced stress, longer life for generator and motor windings
PowerRouter® control system enables microgrid operation
− Ride-through, VAR support, harmonic correction
− Peer to peer aggregation of DER generation and storage assets
− No high speed communication required
− Modeless transition between grid & isolated operation
•
Cost
•
•
•
FlexPhase design allows reduction in power switch costs
Modular design well suited for reduced manufacturing cost
Size
•
High power density for reduced footprint
10
210
© 2006
Northern Current DER Applications
Trend to use PE with conventional DER assets
•
•
Standardized grid interface across applications
Elimination of fault current contribution
• Simplifies interconnect approval
• Allows interconnection to constrained systems
•
•
Adds variable speed capability
Enables advanced power system architectures
• PowerRouter® controls
− Microgrid and critical load support applications
• PowerDistributor™ system
− Interconnect DER asset(s) to multiple service entrances
11
© 2006
MicroGrid Power Network Test System
12
211
© 2006
PowerDistributor™ DER System
Utility Distribution System 2
Utility
Utility Distribution System 1
PowerDistributor
Converters
(each metered service)
Transformer
Transformer
Transformer
Meter
Meter
Meter
Load
Service
Panel
Load
Service
Panel
Load
Service
Panel
Customer
Heat Load
Customer Electrical
Service B
Customer Electrical
Service B
Customer Electrical
Service C
© 2006
13
DER Utility Interface Switch
• Flexible, universal interface
for connecting single or
multiple DER systems
• Controls for CB, SCR, or
IGBT switching modules
Bypass
SA
CB
CB
DG
3
3
3
• Enables
Load
• Critical load support
• Intentional islanding
• Enhanced power quality
• Anti-islanding protection
CT
Grid
14
212
DSP: Relay + Comm
+ Monitoring/
Diagnostics
Meas
Com
© 2006
SmartView® DER Management System
15
© 2006
For more information, contact:
Jonathan Lynch
(802) 583-7224
[email protected]
Northern Power Systems
182 Mad River Park
Waitsfield, Vermont 05673 USA
www.northernpower.com
16
213
© 2006
SMA America
Advanced Power Electronics Interfaces Workshop
August 24, 2006
Who We Are And What We Do
„ Founded in 1981
„ Headquartered in Niestetal, Germany
„ Approx. 1,200 employees worldwide,
more than 15 % are engineers
„ Technology leader and trend-setter
„ Privately held Ag corporation
2
214
Where We Are
„
Office recently opened in Korea
3
Product areas
4
215
Synergies of key competence areas
5
US Inverter Products and Applications
„ Residential PV, Small Wind, Hydro
†
SB1800U, SB2500U
†
SB700U, SB1100U
†
SB3300U, SB3800U, SB6000U
„ Commercial PV
†
SC125U
„ Back-up Power and Off-grid
†
SI4248U (partially funded by PIER)
„ AeroSmart Wind Turbine
„ Further expansion of product family by 2007
6
216
Trendsetting Communication Services
„ Communication products
†
Web Box
– Communication hub and
system data logger
†
Sunny Portal
– Free internet system
performance server
„ Services
†
†
Automated notification of
performance and system
alarms.
Automated performance
analysis and notification
7
The Future of Distributed Energy
AC coupling: The best solution for flexibility and efficiency of off-grid
and back-up supplies.
Sunny Island
4248
Sunny Island
4248
Sunny Boy
Windy Boy
AC
bus
Consumer
Generator
8
217
Design Improvements
„ Opti-Cool forced-air cooling
„ IGBT skip-packs
„ Integrated aluminium
enclosure and heat-sink
„ Ethernet communication
„ Load-break rated DC fused
disconnect
„ HALT/HASS testing
9
New Inverter Family Introduction
„ Over 98% peak efficiency inverter topology
„ Advanced communication and control features
„ System performance analysis
„ Intelligent off-grid & back-up power integration
„ Intelligent three-phase integration to prevent generation
imbalance
10
218
Recent History in the PV Market
„ PV module prices increase 30% in 2 years.
„ Inverter competition is high due to PV module shortages.
„ IEEE-1547.1 has doubled regulatory certification costs (apr.
$100,000 per inverter).
„ One time CEC rebate system rewards on name-plate ratings
rather than system performance.
„ CEC rebate continues to decline ($2.60 per Watt).
„ Copper, steel, specialty metals increased 40% in the last year.
„ SB1 passed, rebate may return to $2.80 per Watt.
„ CEC Pilot Performance-Based Incentive Program is a step in
the right direction.
11
Recent History at SMA
„ SMA has reduced inverter prices by 20%
over 2 years.
„ Our aim is 5% per price reduction per year.
„ Reliability and functionality has dramatically
improved with new products.
„ Advanced communication products
positioned to:
† Energy reporting for performance based
incentives.
† REC recording and trading
12
219
Moving Forward
„ Shift to performance based incentives
†
Define equipment and metering requirements.
„ Acceptance of transformerless inverter technologies by AHJ’s
†
Immediate adoption of the NEC-2008 Article 690 upon
publication.
„ Ease regulatory requirements
†
UL has become a barrier to flexibility, responsiveness and
innovation.
„ Streamline accounting/reporting requirements for PIER funding to
attract established companies.
13
Kent Sheldon
Sales Support Manager
SMA-America, Inc.
12438-C Loma Rica Drive
Grass Valley, CA 95945
530.273.4895 ext 107
www.sma-america.com
14
220
Appendix E. Additional Resources
221
Power Electronics Activities at ISET
Power Electronics for Grid Interfacing
Power Quality
Microgrids
Stand-alone Systems
Dr.-Ing. A. Engler
This presentation gives an overview about ISETs power electronics
activities with regard to DER and grid integration
222
2
Modular Systems Technology
Concept, proof of concept
1993 - 1998
Components, control
1998 – 2001
Source: SMA Technologie AG
Interconnection, communication,
protection, EMS, 2001 - 2005
APEI-Workshop, August 2006, Dr. Ing. A. Engler
„Modularity“ has been a major topic at ISET for about 15 years!
E. g. within the frame of three national projects a modular concept has
been developed. A whole DER-component family has been developed
and transferred to commercial products (SMA). The next step have
been the integration and interconnection issues.
223
3
Development of PV- and Battery Inverters
Hardware of PV-Inverter
Hardware of Battery-Inverter
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Development of commercial inverters in the kW-range for major PVcompanies as SMA, KACO, etc.
224
4
Code Generation for Embedded Controllers
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Embedded code generation by means of modern development tools
enabling partially graphical implementation.
225
5
selfsync®: Droop control for inverters
(patented in Europe and US)
Inverters are controlled by droops:
u
f
u0
f0
Δf
-1
0
1
-1
P
PN
Frequency droop
-4%
Δu
-1%
0
1
Q
QN
Voltage droop
The special implementation of droops with the selfsync® algorithm enables
synchronisation and load sharing of inverters without communcation!
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Development of efficient control algorithms especially for stand-alone
systems and Microgrids.
226
6
Load sharing and frequency change (selfsync®)
60
50.0
*103
50
49.8
40
49.6
30
49.4
20
49.2
10
49.0
0
0.0
0.2
(file 3_UMRICHTER.pl4; x-var t) t: PV
0.4
t: PV1
0.6
0.8
[s]
t: PV2
Loadsharing: contribution depends
on set-point of the idle frequencies
1.0
48.8
0.0
0.1
0.2
0.3
0.4
0.5
[s]
0.6
(file 3_UMRICHTER.pl4; x-var t) t: FR t: FR1 t: FR2
Frequency could be restored by
a secondary control
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Selfsync® enables load sharing between inverters bettern than 1 %!
227
„Indirect operation“ of droops in case of resitive
coupling (LV-case)
- Applied droop concept is based on
inductive coupled voltage sources.
- In a LV-grid components are coupled
resistively, thus voltage determines
the active power distribution
- There are two effects of droops
- direct (inductive coupling)
- indirect (resitive coupling)
f
u
u0
f0
Δf
-1
- The „indirect“ effect requires droops,
which have the same sign for the
frequency as well as the voltage droop
and therefore the stable operation point
is „in phase“.
0
Δu -4%
-1%
1P
PN
-1
0
1Q
QN
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Selfsync® is applicable in LV-, MV and HV-Grids!
228
7
Stability assessment of multi-inverter systems
(selfsync®)
Stable and unstable
operating points
MatLab/Simulink model based on mean
frequency coupling
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Inverters co-ordinated with selfsync® are scalable: One can operate as
many inverters in parallel as necessary. They can be of different size
(practically a ratio of 1 : 100 shouldn‘t be exceeded). By special means
even dynamical loadsharing can be ensured.
229
8
9
Electronic switch: possible faults (selfsync®)
400
420
440
460
480
500
520
540
560
580
600
560
580
600
vMicroGrid [v]
300
0
-300
100
80
grid connected
60
island
IMicroGrid [A]
40
20
0
-20
-40
-60
-80
-100
1000
800
600
400
IGrid [A]
200
0
-200
-400
-600
-800
-1000
400
420
440
460
480
500
520
540
time [ms]
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Selfsync® masters all possible grid faults, even near short circuits. A
fast disconnection device is required.
230
10
High Impedance Grid fault (selfsync®)
Grid
Isolated
Grid
i_USV
i_Load
no transition!
Principally the suggested control mode also continuous operation even in
case of a line interruption. A grid failure mostly results not in an interruption but in a short-circuit and therefore motivates the development
of a disconnection device!
APEI-Workshop, August 2006, Dr. Ing. A. Engler
As the operation mode is not changed between island und grid
operation, there is almost no transition time.
231
11
Increasing short circuit power (selfsync®)
Single phase inverter grid
(DeMoTec, ISET)
Short circuit:
triggering a circuit breaker
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Standard protection devices can be used with Selfsync® .
232
Parallel operation of an ASG and Sunny Islands
(selfsync®)
Load sharing between Sunny Island and genset is possible due to the
inherent frequency / active power characteric of the genset (slip, mechanical
controller)
Single phase genset with ASG and
capacitor (Fa. Kirsch)
Synchronising a Sunny Island onto
the genset (idle frequency set for
charging)
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Selfsync® is compatible with standard diesel gensets.
233
12
13
Rapid prototyping of 100kVA inverter control
dSpace System
interfaces
APEI-Workshop, August 2006, Dr. Ing. A. Engler
ISET develops advanced control algorithms for 100 kVA to 1 MVA
inverters.
General Advantages of „Rapid Prototyping“:
• Control algorithms are developed using MatLab/Simulink simulation
software. Tested and working models can directly be used in the
prototype.
• Automatic code generation for the architecture of the RapidPrototyping-System.
• Integration of custom C-code possible
• Quick and effective development even of advanced control algorithms
due to high computing power of the Rapid-Prototyping-System.
• Online visualization of all variables
• Adjustment of variables i.e. controller parameters during operation
234
14
Development of Power Quality Equipment
with rapid prototyping
Prototype, 3.3 kVA, 16 kHz switching frequency, usable energy storage 470 Ws
Host PC with
integrated
Rapid-Prototyping
-System
Distorting load,
Dimmed light bulbs
Power Quality
Monitoring equipment
External interface board of the
Rapid-Prototyping-System
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Realised functions:
• Voltage dependent supply of reactive power (Q droop)
• Dynamic reactive power compensation of dedicated loads
• Dynamic harmonics compensation of dedicated loads
• Flicker reduction
•Local improvement of voltage quality by inductively decoupled subnetworks
235
15
RMS current (A)
260
250
240
230
220
210
200
20
15
10
5
0
Q (kVAr)
RMS voltage (V)
Development of Power Quality Equipment:
Q-Droop: Grid Support with Reactive Power
3
2
1
0
-1
-2
-3
U1
UDGFACTS
0
20
40
60
Time (s)
80
100
0
20
40
60
Time (s)
80
100
0
20
40
60
Time (s)
80
100
120
Inverter injects
reactive power
according to the
line line voltage
and supports it
depending on the
120 line impedance
120
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Realised functions:
• Voltage dependent supply of reactive power (Q droop)
• Dynamic reactive power compensation of dedicated loads
• Dynamic harmonics compensation of dedicated loads
• Flicker reduction
• Local improvement of voltage quality by inductively decoupled subnetworks
236
16
DeMoTec at ISET
Interconnected Grid
Loads
Switching Cabinet
Diesel generator
Medium Voltage Grid
PV
Wind Energy Converter
APEI-Workshop, August 2006, Dr. Ing. A. Engler
The design, demonstration and test center (DeMoTEC) at ISET enables
a variety of relevant tests for DER-components.
237
17
Interconnecting distribution systems (MV- and LV-Grids)
Diesel-Kraftwerk
Diesel Power Station
Photovoltaik
Photovoltaic
Hybridsystem
Hybrid System
0,4 kV
0,4 kV
10/ 20/ 30 kV
10/ 20/ 30 kV
Medium-voltage grid
emulator
Windpark
Wind Park
10/ 20/ 30 kV
0,4 kV
Line
equivalent
Blockheizkraftwerk BHKW
Combined Heat & Power Sta tion CHP
APEI-Workshop, August 2006, Dr. Ing. A. Engler
The Medium voltage grid emulator enables test of equipment for MVdistribution systems.
238
18
Example for laboratory installation
APEI-Workshop, August 2006, Dr. Ing. A. Engler
239
19
Laboratory demonstration
- Starting diesel genset (tertiary control) -
Screenshot
Of
SCADA-System
APEI-Workshop, August 2006, Dr. Ing. A. Engler
The development of SCADA-Systems and supervisory control
algorithms enables energy management of grid connected or remote
hybrid systems.
240
20
Greek Island Kythnos
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Example of small hybrid system installed by ISET and SMA.
241
21
Greek Island Kythnos
APEI-Workshop, August 2006, Dr. Ing. A. Engler
Example of small hybrid system installed by ISET and SMA.
242
22
Conclusion
- ISETdevelops power electronics for commercial production
- ISET develops advanced control algorithms for grid interfacing
- ISET is able to test equipment in laboratory and field tests
- ISET is a non-profit organisation
ISET e. V
Königstor 59
34119 Kassel
Germany
APEI-Workshop, August 2006, Dr. Ing. A. Engler
243
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Advanced Power Electronics Interfaces for Distributed Energy
Workshop Summary: August 26, 2006, Sacramento, California
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11. SPONSORING/MONITORING
AGENCY REPORT NUMBER
12. DISTRIBUTION AVAILABILITY STATEMENT
National Technical Information Service
U.S. Department of Commerce
5285 Port Royal Road
Springfield, VA 22161
13. SUPPLEMENTARY NOTES
14. ABSTRACT (Maximum 200 Words)
The Advanced Power Electronics Interfaces for Distributed Energy Workshop, sponsored by the California Energy
Commission Public Interest Energy Research program and organized by the National Renewable Energy Laboratory,
was held Aug. 24, 2006, in Sacramento, Calif. The workshop provided a forum for industry stakeholders to share
their knowledge and experience about technologies, manufacturing approaches, markets, and issues in power
electronics for a range of distributed energy resources. It focused on the development of advanced power electronic
interfaces for distributed energy applications and included discussions of modular power electronics, component
manufacturing, and power electronic applications.
15. SUBJECT TERMS
power electronics; distributed energy; DER; workshop; advanced power electronics initiative; California Energy
Commission; CEC; National Renewable Energy Laboratory; NREL
16. SECURITY CLASSIFICATION OF:
a. REPORT
b. ABSTRACT
Unclassified
Unclassified
c. THIS PAGE
Unclassified
17. LIMITATION
18. NUMBER
OF ABSTRACT
OF PAGES
UL
19a. NAME OF RESPONSIBLE PERSON
19b. TELEPHONE NUMBER (Include area code)
Standard Form 298 (Rev. 8/98)
Prescribed by ANSI Std. Z39.18
F1147-E(12/2004)
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