Recent US Wind Interconnection Experience

Transcription

1 Wind Energy and Grid Integration Recent US Wind Interconnection Experience J. Charles Smith Nexgen Energy LLC Utility Wind Integration Group January 24-25, 2006 Madrid, Spain

2 Outline of Topics Background Evolution of US Grid Code Activities Summary of Wind Interconnection Best Practices System Stability Case Study

3 What is UWIG? Non-profit corporation established by 6 utilities in 1989 with support from EPRI and DOE/NREL Current membership totals 85, including Associate Members from wind development, equipment, and consulting community Focus on technical issues Mission: To accelerate the appropriate integration of wind power into the electric system

4 Alphabet Soup DOE: Department of Energy NREL: National Renewable Energy Laboratory EPRI: Electric Power Research Institute FERC: Federal Energy Regulatory Commission NERC: North American Electric Reliability Council AWEA: American Wind Energy Association UWIG: Utility Wind Integration Group IEEE: Institute of Electrical and Electronics Engineers PES: Power Engineering Society ERO: Electric Reliability Organization WECC: Western Electricity Coordinating Council MISO: Midwest Independent System Operator CANWEA: Canadian Wind Energy Association POI: Point of interconnection LVRT: Low Voltage Ride Thru

5 Grid Codes in North America Activity initiated in US by AWEA in 2003 after August blackout AWEA Grid Code filed with FERC in May 2004 Three major issues covered LVRT, reactive power supply, and SCADA capability for wind plants Filing resulted in FERC Technical Conference in Sept 2004 and initial order in July 2005 Additional activity underway in WECC and Canada (Alberta and Hydro Quebec) CANWEA just released grid code report by Garrad Hassan

6 Energy Policy Act of 2005 Requires mandatory and enforceable electric system reliability standards Electric Reliability Organization (ERO) will be established to administer the standards FERC will have oversight of the ERO FERC must establish rules for ERO operation by Feb 06 NERC has prepared application to become ERO NERC Version 0 reliability standards (91 standards for planning and operation) expected to be adopted by FERC NERC expected to be certified as ERO by August 06

7 NERC Regions & Control Areas

8 NERC Update NERC Wind Generation Task Force created by Transmission Issues Subcommittee of Planning Committee in Dec 04 to: Review bulk electric system reliability implications/concerns of wind generation Develop Standard Authorization Request if existing standards do not adequately address the concerns NERC filed Request for Rehearing on FERC Order 661 in July 05 due to concerns over: Low voltage ride through (LVRT) requirement Burden of proof for complying with good utility practice

9 FERC Update July 2003: Order 2003 March 04: Order 2003 A September 04: Grid Code Technical Conference July 2005: Order 661 July 2005: NERC Request for Rehearing December 2005: Order A

10 FERC Order 2003 FERC Order on Large Generator Interconnection Issued in July 2003 Addressed lack of uniformity in interconnection procedures for generators larger than 20 MW Large Generator Interconnection Procedure Large Generator Interconnection Agreement No distinction between interconnection requirements for synchronous and induction machine or those with power electronic converters

11 FERC Order A Amendment to FERC Order 2003 Issued in March 2004 Result of stakeholder comments Recognized that electrical machine technology differences affected interconnection requirements Included Appendix G blank sheet of paper to accommodate unique concerns of wind plant developers

12 FERC Order 661 Addresses technical requirements for interconnection left open in Appendix G AWEA filed Petition for Rulemaking in May 2004 covering basic elements of grid code for wind plants FERC held Technical Conference in Sept Order issued in July 2005

13 Order 661 Provisions LVRT Generator stays on line for up to.625 sec during a voltage dip as low as.15 pu at the POI, if needed for safety or reliability Reactive power Provide power factor of +/-.95, and dynamic voltage support, if needed for safety or reliability SCADA Provide necessary information, as agreed with transmission provider

14 FERC Order A NERC immediately filed Request for Rehearing in July 2005 FERC ordered NERC and AWEA to resolve their differences and report back to FERC Order issued in December 2005 as amendment to FERC Order 661 refining the provisions of the original order

15 Order 661 A Provisions LVRT Generator stays on line during a 3 phase fault for normal fault clearing time up to 9 cycles and SLG faults with delayed clearing during a voltage dip as low as.15 pu at the high side of the GSU for units in service before 2008 Voltage dip requirement extends to 0.0 pu in 2008 Reactive Power Provide power factor of +/-.95, including dynamic voltage support, if needed for safety and reliability Partial dissent by Chairman Kelliher over lack of mandatory requirement, ie placing burden of proof on transmission provider SCADA Provide necessary information, as agreed with transmission provider

16 FERC Order 661 and WECC LVRT Standards Minimum Required Wind Plant Response to Emergency Low Voltage Beginning of Emergency Low Voltage Wind P lant Required To Remain On-line Wind Plant Not Required to Remain On-line Time (seconds) * per unit = Ratio of Actual to Nominal Voltage Reference: Zavadil et al, IEEE Power & Energy Magazine, November/December 2005 To be published

17 Ongoing Activity MISO filed tariff modification for Order 661 A in December 05 Requests flexibility on 9 cycle clearing time for LVRT requirement Requests reactive capabilty of +/-.95 as standard, with continuous dynamic capability AWEA and Wind on the Wires intervened in January 06 Protested MISO s filing Requested FERC to reject the proposed variations from Order 661A It ain t over till it s over!

18 Emerging Best Practices on Interconnection Requirements Proven technology, already implemented internationally Voltage regulation at the Point-of-Interconnection, with a guaranteed power factor range Low voltage ride through A specified level of monitoring, metering, and event recording Power curtailment capability Wind plant forecasting capability Features emerging in response to system needs Ability to set power ramp rates Zero-power voltage regulation Reserve functions Governor functions Inertial response functions

19 Wind Plant Control Considerations Current wind generation technology provides for advanced operational capabilities short-term smoothing of power fluctuations Participation in automatic generation control So why not change how wind plants operate? Only if economics allow Control costs money in the form of decreased production Wind plant control might be significantly more expensive than alternatives in terms of $/MW or MWH of control capability

20 System Stability Case Study Wind integration and interconnection study conducted by GE for NYISO, supported by NYSERDA Looked at impacts of 3,300 MW of wind generation on 33,000 MW peak load system (10%) Stability case study investigated differences in behavior with 3,300 MW of wind plant with generic doubly fed induction machines, distributed throughout the state, replacing 3,300 MW of conventional plant

21 Marcy 345kV Bus Voltage (pu) With Wind Impact of Wind Generation on System Dynamic Performance Fault at Marcy 345 kv bus Severe contingency for overall system stability Without Wind Total East Interface Flow (MW) Without Wind Simulation assumes vectorcontrolled wind turbines Wind generation improves postfault response of interconnected power grid With Wind source:ge/nyserda

22 Wind Going Mainstream IEEE takes note of wind New Wind Power Coordinating Committee approved by PES Technical Council at Annual Meeting in San Francisco in June, 2005 PES Power and Energy Magazine special issue devoted to Utility Wind Power Integration in November December 2005 Four IEEE Societies and NERC will cooperate with UWIG and AWEA to conduct a symposium on Wind Power: Technology, Economics, and Politics in Washington in April, 2006

23 Special Issue on Utility Wind Integration

24 Visit Phone For More Information Charlie Smith Bob Zavadil x 149 Fax Mail Utility Wind Integration Group PO Box 2787 Reston, VA USA