200 likes | 310 Views
Grid Interconnection and Power Quality Assessment of Distributed Resources. Farid Katiraei Ph.D. Candidate Department of Electrical and Computer Engineering University of Toronto. Wind Power Generation Symposium Feb. 20, 2004. Outline. DR connection process Utility impact assessment
E N D
Grid Interconnection and Power Quality Assessment of Distributed Resources Farid Katiraei Ph.D. Candidate Department of Electrical and Computer Engineering University of Toronto • Wind Power Generation Symposium • Feb. 20, 2004
Outline • DR connection process • Utility impact assessment • Interconnection requirements • Power quality issues • Case studies: A Hybrid system
Standards and Regulations • “IEEE Std. 1547, for interconnecting Distributed Resources with Electric Power System”, IEEE Standards, July 2003 • CSA Standard CAN3-C235, C325, C107.1 • “MicroPower Connect Interconnection Guideline”, July 2003 • Ontario Electrical Safety Code (OESC) • Ontario Energy Board Act, 1998 ( sec. 27.1) • Electric Safety Authority (ESA)
DR Connection Process • Step 1: Basic planning - Data collection and Plan development, - Environmental assessment • Step 2: Feasibility study -Utility impact assessment, - Electrical inspection requirements (ESA) • Step 3: Implementation - Detailed design and review, - Basic interfacing equipments, - ESA plan approval • Step 4: Commissioning & Authorization of the connection • Step 5: Operation & Maintenance
Utility Impact Assessment • Power quality assessment • Interconnection requirements • line/equipment upgrades • Grounding • Power flow • System protection modification • Fault currents, re-coordination • Synchronization
Power Quality Issues • Voltage regulation (Load dependent) • Voltage fluctuation (not greater than 5%) • Flicker (No objectionable flicker) • Voltage Unbalance • Harmonic injection (TDD,THD < 5%) • DC injection (< 0.5% of In) • Reactive power requirements (Preferred pf. : 0.9 lag 0.95 lead) • Surge withstand performance ( up to 220% of the rated voltage)
Study system • Impact assessments of a Hybrid system: DG1: 2 MVA gas-fired diesel generator DG2: 2.5 MVA electronically-interfaced DG3: 1.5 MW wind turbine (Rotor diameter 76m, Wind speed: 5-25 m/s, Hub height: 64m) Load demand: Sensitive load, Industrial/Residential load • Case I: Wind turbine start up • Scenario 1: Grid interconnected system • Scenario 2: Stand-alone system • Case II: Short circuit analysis • Line-Ground fault on the Utility side, Fault clearing
Wind turbine start up • Direct connected generators: • Speeding up with the wind, connection at 85% of synchronous speed • Soft starter, limit start up current • Second winding (two speed turbines) • Electronically interfaced: • Synchronization • Wind farm: • Sequential start up
I-1: Grid Connected System • Bus voltages • - Startup @ t=2.0 s
I-1: Grid Connected System • Power variation • - Startup @ t=2.0 s
I-2: Stand-alone System • Bus voltages • - Startup @ t=2.0 s
I-2: Stand- alone System • Power variation • - Startup @ t=2.0 s
Case II: Fault Analysis • Voltage fluctuation • - Fault @ t=0.5 s • - Clear @ • t=0.58 s
Case II: Fault Analysis • Freq. variation • -Fault @ t=0.5 s • -Clear @ • t=0.58 s • -Reconnect • @ t=1.08s
Conclusion • Comprehensive study of the system • Steady-state analysis • Dynamic Analysis • Appling uniform interconnection Standards