3 Phase & 1 Phase UPS Robert Lyga Gamatronics Agenda • Module 1 – Modular UPS technology-3-Phase – – – – – Basics of Modular UPS technology Centralized vs Decentralized Battery Planning for Capacity and Future Growth N+1 Redundancy Methods – Modular UPS vs Single Size UPS Reliability/Maintenance of Today’s Modular Systems • Module 2 – Single Phase Technology – Methods of achieving long run times – Charging batteries in multiple battery packs Basics of Modular UPS Technologies Traditional UPS consists of single rectifier and inverter sized for full capacity of UPS. – System may not be upgradeable for future expansion • Replacement with larger system required • High cost of expansion – System may need to be oversized today for correct size in future • Higher cost of UPS today – Failure of the rectifier or inverter transfers the loads to static bypass • Lower reliability due to single points of failure • Redundancy can be done but at a higher cost 80kVA Rectifier Inverter ~ = ~ • Lower efficiency and higher Cost of Operation while undersized = • Basics of Modular UPS Technologies • Today’s modular UPS system – Can be configured from 10kVA to 100kVA • 10kVA to 12kVA power modules • UPS capacity based on the # of modules • Modules can be added to increase capacity, redundancy, or charging – Each module contains rectifier and inverter – Control system may be in each module or at system level • Module level control with master – slave relationship Basics of Modular UPS Technologies • Modular UPS consists of multiple, smaller rectifier/inverter modules. – System can be upgraded with addition of power modules as loads grow • System does not have to be replaced • Lower cost of expansion – Customer purchases the correct size UPS today and the UPS can grow as needed. • Lower initial investment • UPS can be operated at % load that give the best efficiency and operating cost – One rectifier or inverter may fail without causing the UPS to transfer the loads to static bypass • Remaining modules may support the load • Higher reliability due to lack of single point of failure • Redundancy can be done at lower cost at the module level 80kVA Centralized vs Decentralized Battery • Centralized Battery Centralized vs Decentralized Battery • Centralized Battery – Batteries are charge simultaneously by all modules, independent of the integrity of the individual modules – Backup time not affected by faulty module – Optional addition of battery strings in parallel – High reliability – Charge current control and monitoring according to battery capacity – Operation unaffected by rectifier failure in one of the modules Centralized vs Decentralized Battery • Decentralized Battery Centralized vs Decentralized Battery • Decentralized Battery – End-of-discharge disconnection voltage is determined by the weakest battery set. – An inverter failure in one of the modules reduces the backup time – A rectifier failure in one of the modules excludes its battery set as well as its inverter output. – Over current condition may develop in the remaining battery sets in case of a module failure – Problematic maintenance of multiple battery sets (hundreds of batteries per system!) – Downgrade of battery reliability due to so many batteries that are liable to fail Planning for Capacity and Future Growth • Planning for Capacity – Determine the amount of load as normal • Consider start surges and periodic loads as needed – Select a UPS size based on current capacity requirements – Select battery system to meet runtime needs. – Determine the type of maintenance bypass required Planning for Capacity and Future Growth • Planning for Future Growth – Select UPS chassis that is scalable to future needs – Select battery system that is scalable or with proper over current protection – Size maintenance bypass to allow UPS growth – Size wiring for future capacity N+1 Redundancy Methods • Single Size UPS 2 units of 80kVA provide N+1 Redundancy N+1 Redundancy Methods • Single Size UPS – High initial capital cost • Must Purchase 2 large UPS system – High installation cost • Must install 2 systems – Lower efficiency = higher operating cost • Systems operating at 50% load – 2X footprint • Floor space may not be available • Square foot cost N+1 Redundancy Methods • Modular UPS 10kVA 10kVA 10kVA 10kVA 10kVA 10kVA 10kVA 10kVA + 80kVA 10kVA 8 x 10kVA for Capacity plus 1 x 10kVA for N+1 Redundancy N+1 Redundancy Methods • Modular UPS – Low initial capital cost • Add one additional module for N+1 redundancy – Lower installation cost • Install a single UPS system – Lower efficiency = higher operating cost • All modules operating at higher % load – Single UPS footprint • Lower floor space costs Reliability / Maintenance of Today’s Modular Systems • Reliability – Scalability allows operation at optimal % load – N+1 redundancy increases system reliability • Maintenance – Achieved on modular lever – Lower MTTR – Lower labor costs for repair – Spare parts = spare module Single Phase UPS Technologies • Methods of achieving long runtimes – Single battery systems with large wpc batteries • Typical for larger single phase UPS • May not be available for smaller UPS • High initial cost • Difficult to add incremental runtime • May require a large charger Single Phase UPS Technologies • Methods of achieving long runtimes – Multiple external battery packs (EBP) • Typical for smaller UPS • Use smaller wpc batteries in each pack • Lower initial cost • Can add incremental runtime • Charging method dependant on system Single Phase UPS Technologies • Methods of achieving long runtimes – Multiple external battery packs (EBP) Single Phase UPS Technologies • Charging batteries in multiple battery packs – Single charger in UPS • May be too small for total battery • Battery packs may receive different charge voltage and current – Chargers in each battery pack • Charger sized correctly for the pack • Each pack receives correct current and voltage Single Phase UPS Technologies • Charging batteries in multiple battery packs – Chargers in each battery pack Questions?