Control System Toolbox Release Notes

Control System Toolbox Release
Notes
The “Control System Toolbox 5.2 Release Notes” on page 1-1 describe the
changes introduced in the latest version of the Control System Toolbox.
The following topics are discussed in these Release Notes:
• “New Features” on page 1-2
• “Major Bug Fixes” on page 1-5
• “Platform Limitations for HP and IBM” on page 1-6
The Control System Toolbox Release Notes also provide information about
the earlier versions of the product, in case you are upgrading from a
version that was released prior to Release 12.1. If you are upgrading from
a release earlier than Release 12.1, you should also see
• “Control System Toolbox 5.1 Release Notes” on page 2-1
• “Control System Toolbox 5.0 Release Notes” on page 3-1
Printing the Release Notes
If you would like to print the Release Notes, you can link to a PDF version.
-2
Contents
Control System Toolbox 5.2 Release Notes
1
New Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Response Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LTI Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SISO Design Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Enhancements to Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-2
1-2
1-2
1-3
1-4
Major Bug Fixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
allmargin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
dlinmod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
place . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-5
1-5
1-5
1-5
Platform Limitations for HP and IBM . . . . . . . . . . . . . . . . . . 1-6
Preference and Property Editors . . . . . . . . . . . . . . . . . . . . . . . . 1-6
SISO Design Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Control System Toolbox 5.1 Release Notes
2
New Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
SISO Design Tool Enhancements . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Algorithmic Enhancements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Control System Toolbox 5.0 Release Notes
3
New Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
SISO Design Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
LTI Viewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
iii
Property and Preference Editors . . . . . . . . . . . . . . . . . . . . . . . . .
Algorithmic Enhancements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
New Demo Suite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
iv
Contents
3-3
3-3
3-3
3-3
1
Control System Toolbox
5.2 Release Notes
New Features . . . . .
Response Plots . . . . . .
LTI Viewer . . . . . . .
SISO Design Tool . . . .
Enhancements to Functions
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1-2
1-2
1-2
1-3
1-4
Major Bug Fixes
allmargin . . . .
dlinmod . . . .
place . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1-5
1-5
1-5
1-5
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Platform Limitations for HP and IBM . . . . . . . . 1-6
Preference and Property Editors . . . . . . . . . . . . 1-6
SISO Design Tool . . . . . . . . . . . . . . . . . . 1-6
1
Control System Toolbox 5.2 Release Notes
New Features
This section summarizes the new features and enhancements introduced in the
Control System Toolbox 5.2.
If you are upgrading from a release earlier than Release 12.1, then you should
see “New Features” on page 2-2 in the Control System Toolbox 5.1 Release
Notes.
Response Plots
New features for response plots include
• Normalization of time plots for easy trend comparison
• Driving input signal shown in linear simulation (lsim) plots
• Standard zooming for all response plots
• A Full View right-click menu
• Ability to toggle magnitude and phase visibility in Bode plots
• In Bode plots, a modified phase correction algorithm that produces
consistent phase at w=Inf and is robust to perturbations of the pole/zero
structure at the origin
• Showing only positive frequencies in Nyquist plots
• A new function, iopzmap, that plots the transfer poles and zeros for each I/O
pair in a MIMO system
LTI Viewer
The LTI Viewer no longer restricts importing models with unequal numbers of
inputs and/or an unequal numbers of outputs. You can import any combination
of LTI models into the viewer.
The zoom property in the LTI Viewer’s right-click menu has been removed. You
can access this functionality from the new toolbar.
The import and export dialog boxes are now easier to use.
The LTI Viewer now seamlessly imports SISO models from the System
Identification Toolbox. The noise model is automatically discarded and the
IDMODEL is converted to ZPK format.
1-2
New Features
SISO Design Tool
The following are new features in the SISO Design Tool.
Additional Feedback Structures
The SISO Design Tool has support for two new feedback structures:
• Feedforward configuration
• Cascade configuration with filter F in the minor loop
All the usual functionality (e.g., graphical tuning of F and G) are available in
the new feedback structures.
Analysis Menu
The SISO Design Tool contains a new Analysis menu that raises Loop
Responses under Tools to the top level. New plots available from this menu
are
• Input disturbance rejection
• Output disturbance rejection
Real-Time Updating of Linked LTI Viewers
LTI Viewers that are linked to the SISO Design Tool update response plots in
real-time during mouse-driven compensator tuning. This is the default
behavior. To deactivate this feature, clear the Real-Time Update check box in
the linked LTI Viewer. In this case, plots update only when you release your
mouse.
Import of System Identification Toolbox Models
The SISO Design Tool now seamlessly imports SISO models from the System
Identification Toolbox. The noise model is automatically discarded and the
IDMODEL is converted to ZPK format.
Reworked Store and Retrieve Windows
A new window, the Design Archive, combines both store and retrieve
functions within a single, more intuitive GUI.
1-3
1
Control System Toolbox 5.2 Release Notes
Nichols Plots
You can now trace the frequency by placing your mouse cursor over the Nichols
contour.
Enhancements to Functions
The c2d function has a new impulse-invariant discretization method that
guarantees matching continuous and discrete responses for pulse inputs.
1-4
Major Bug Fixes
Major Bug Fixes
The Control System Toolbox 5.2 includes several bug fixes made since Version
5.1. This section describes important Version 5.2 bug fixes.
allmargin
The allmargin function converts ZPK models to TF format only when there is
an algebraic loop in your system. This change ensures that the SISO Design
Tool can correctly diagnose closed-loop stability (open loop is always in ZPK
format).
dlinmod
The dlinmod function now correctly linearizes all multirate discrete or hybrid
(continuous and discrete) Simulink models when using Jacobian-based
linearization.
place
Formerly, bad edge cases in the orthogonalization loop caused a divide by zero
in the place function. This is no longer the case.
1-5
1
Control System Toolbox 5.2 Release Notes
Platform Limitations for HP and IBM
Note The platform limitations for the Control System Toolbox 5.2 are the
same as they were for Version 5.1. Those limitations are described below.
Preference and Property Editors
The Toolbox Preferences Editor and Response Property Editor are not
supported on HP and IBM platforms. The LTI Viewer Preferences Editor is
supported with a reduced set of features (no tools to set preferences for grids,
fonts, colors, or phase wrapping).
SISO Design Tool
The following features are not supported for the SISO Design Tool on HP and
IBM platforms:
• Preference and property editing
• Compensator format editing
• Storing and retrieving compensators
• Design constraints
In addition, the SISO Tool Export window has fewer export options.
1-6
2
Control System Toolbox
5.1 Release Notes
New Features . . . . . . . . . . . . . . . . . . . 2-2
SISO Design Tool Enhancements . . . . . . . . . . . . 2-2
Algorithmic Enhancements . . . . . . . . . . . . . . 2-3
2
Control System Toolbox 5.1 Release Notes
New Features
This section introduces the new features and enhancements added in the
Control System Toolbox 5.1 since the Control System Toolbox 5.0 (Release
12.0).
For information about Control System Toolbox features that are incorporated
from Version 5.0, see “New Features” on page 3-2 in the Control System
Toolbox 5.0 Release Notes.
SISO Design Tool Enhancements
Enhancements to the SISO Design Tool include the following:
• Save/load session — You can now save the state of the SISO Design Tool
before exiting and restore it at a later time.
• Graphical design constraints — You can use a new set of design constraints
that you move and shape with the mouse or specify by typing their
parameter values. For example, the design constraints for root locus include
damping ratios, settling time, natural frequency, and percent overshoot.
• Interactive open-loop Nichols plot — You can use a new view to graphically
tune the parameters of the feedback compensator. The open-loop Nichols plot
contains the same functionality as the open-loop Bode diagram and root
locus.
• Interactive Prefilter Design view — You can now interactively shape the
prefilter compensator. Both interactive graphics and a right-click menu are
available.
• New compensator format — You can display compensator transfer functions
in the natural frequency format, which is of the form
( 1 + s ⁄ ωz1 )
dcgain × ------------------------------- …
( 1 + s ⁄ ω p1 )
where ωz1,ωz2, ... and ωp1, ωp2, ..., are the natural frequencies of the zeros and
poles, respectively.
For detailed examples of how to use the SISO Design Tool, see “Designing
Compensators” in Getting Started with the Control System Toolbox.
2-2
New Features
Algorithmic Enhancements
Enhancements to controls algorithms include
• M-circle grid for Nyquist plots
• A new function, bandwidth, that calculates the bandwidth of SISO systems
• LTI models with complex data — You can now specify transfer functions or
state-space models with complex coefficients. Most commands work on such
models, except for the following:
- Time response commands
- rlocus
- margin, allmargin
• New LTI method conj for use with LTI models with complex data (works for
TF, ZPK, SS objects)
2-3
2
Control System Toolbox 5.1 Release Notes
2-4
3
Control System Toolbox
5.0 Release Notes
New Features . . . . . . .
SISO Design Tool . . . . . .
LTI Viewer . . . . . . . . .
Property and Preference Editors
Algorithmic Enhancements . .
New Demo Suite . . . . . . .
Documentation . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3-2
3-2
3-2
3-3
3-3
3-3
3-3
3
Control System Toolbox 5.0 Release Notes
New Features
This section introduces the new features and enhancements added in the
Control System Toolbox 5.0 since the Control System Toolbox 4.2.1 (Release
11.0).
SISO Design Tool
The SISO Design Tool is a new visual interface that greatly simplifies the
design of compensators for single-input, single-output (SISO) linear systems.
Using editable root locus and Bode diagram views, you can graphically adjust
the compensator gain, poles, and zeros, while monitoring the closed-loop
responses and stability margins.
Other features include storing intermediate designs, discretizing the
compensator, and visualizing design constraints.
For detailed examples of how to use the SISO Design Tool, see “Designing
Compensators” in Getting Started with the Control System Toolbox.
LTI Viewer
Enhancements to the LTI Viewer include
• Data markers for scanning data off response plots and annotating plots with
critical response values
• Adaptive S and Z grids for pole/zero and root locus plots
• Sharper Nyquist and Nichols plots with less user intervention
• Option to display all crossover frequencies for gain and phase margins
For detailed examples of how to use the LTI Viewer, see “Analyzing Models” in
Getting Started with the Control System Toolbox.
3-2
Property and Preference Editors
You can use new Property and Preference Editors to set plot options such as
titles, fonts, units, and grids. You can set toolbox preferences to persist from
session to session, or set tool preferences for instances of the LTI Viewer and
SISO Design Tool during a single session. You can also customize individual
response plots using the Property Editor.
For a discussion of how to set properties and preferences, see Customization in
the Control System Toolbox online help.
Algorithmic Enhancements
Enhancements to controls algorithms include
• A new function, allmargin, for computing all crossover frequencies and
corresponding gain margins, phase margins, and delay margins
• A new algorithm for computing stability margins of SISO systems, including
systems with delays
• An enhanced root locus plotting algorithm
New Demo Suite
The Control System Toolbox demos have been upgraded and considerably
expanded. The new demo suite includes basic “getting started” tutorials,
interactive demos, web-based GUI demos, and an extensive set of case studies
covering dc motors, op amplifiers, disk drives, aircraft autopilots, heat
exchangers, and steel rolling mills.
Documentation
The Control System Toolbox documentation has been thoroughly revamped
and now includes the following:
• A new Getting Started with the Control System Toolbox manual, which
introduces the main features of the toolbox through extended examples. The
focus of this book is on basic control engineering tasks, including building
models, analyzing model responses, and designing compensators. The
examples presented use the LTI Viewer and SISO Design Tool extensively.
3-3
3
Control System Toolbox 5.0 Release Notes
• Online documentation, including a complete function reference and a set of
design case studies that demonstrate the advanced capabilities of the
Control System Toolbox.
3-4