1. Year 2006 Report “Better” Managed and Controlled Transmission Grids using Advanced Technological Concepts Aty Edris EPRI Power Delivery & Markets aedris@epri.com

2. 2 © 2007 Electric Power Research Institute, Inc. All rights reserved. Challenges Full Use of Transmission Capacity Maintain Power Delivery Stability, Power and Voltage Stabilities Power Flow Control and Management, Real and “Reactive” Power

3. 3 © 2007 Electric Power Research Institute, Inc. All rights reserved. R&D Work in 2006 Reactive Power Management Operator/planner training simulator for the use of advanced technological ConceptsOperator/planner training simulator for the use of advanced technological Concepts Grid Shock Absorber Concept Bidirectional HVDC Valve and Tripole HVDC ETO-Based STATCOM for Wind Farm FACTS Technology- Information and Knowledge SharingFACTS Technology- Information and Knowledge Sharing

4. 4 © 2007 Electric Power Research Institute, Inc. All rights reserved. Need Expected Results EPRI Interregional Reactive Power Management Initiative Focused Analysis of Reactive Power and Voltage Control In Large Interconnected Transmission Grids Demonstration of Reactive Power-Voltage Control Management Strategy for Prevention or Mitigation of Voltage Instability and Cascaded Failure Problems

5. 5 © 2007 Electric Power Research Institute, Inc. All rights reserved. Interrgional Reactive Power Management EPRIs Interregional Reactive Power Management project aims at developing better methods for efficient use of reactive power resources and voltage control in order to improve power system operation reliability, security, and the functioning of markets. Reactive power planning is a key component. New methods are needed to help planners design systems which remain strong and robust under all conditions and contingencies. 2006 Results Development of highly automated method which identify “critical voltage control areas” in a system (for wide ranging topology, conditions, transfers and contingencies) and the required reactive power reserve solutions which will ensure system security.

6. 6 © 2007 Electric Power Research Institute, Inc. All rights reserved. Voltage Control Area- Changing Shape and size with Load Levels and/or Transmission Contingencies Load Increase and/or Transmission Contingencies

7. 7 © 2007 Electric Power Research Institute, Inc. All rights reserved. 11 Operating Configurations Modes CSC Schematic Structure Marcy Convertible Static Compensator Planner/Operator Training Simulator

8. 8 © 2007 Electric Power Research Institute, Inc. All rights reserved. Planner/Operator Training Simulator for Advanced Transmission Technological Concepts Technical update, Product ID#1012411

9. 9 © 2007 Electric Power Research Institute, Inc. All rights reserved. “Grid Shock Absorber” Implementation On Eastern Interconnection (EI) Implementation of EPRI Converter-Based BTB Technology Voltage supported junctions The idea ! Area 2 Area 1 Grid Shock Absorber SM

10. 10 © 2007 Electric Power Research Institute, Inc. All rights reserved. “Grid Shock Absorber” Implementation On Eastern Interconnection (EI)

11. 11 © 2007 Electric Power Research Institute, Inc. All rights reserved. Impact of Generation Trip on Power Flows

12. 12 © 2007 Electric Power Research Institute, Inc. All rights reserved. Impact of Generation Trip On System Dynamics AC Links DC Links

13. 13 © 2007 Electric Power Research Institute, Inc. All rights reserved. Impact of “Larger” Generation Trip on Power Flows Selected bus voltages with ac ties (a) and dc links (b) in place. Voltages are not from the same buses in the two cases. Technical Assessment of Grid Shock Absorber Proof of Concept Product ID # 1014494

14. 14 © 2007 Electric Power Research Institute, Inc. All rights reserved. Bidirectional HVDC Valve and Tripole Concepts Objectives Enabling power reverse on a DC transmission, without reversing Voltage Polarities at the transmission ends Tapping of existing HVDC lines AC to DC line conversion Providing a means for more reliable, less costly applications of Cross Link Polyethylene (XLPE) cable for submarine & underground

15. 15 © 2007 Electric Power Research Institute, Inc. All rights reserved. Conversion of an AC Line into a Tripole DC Line Higher $$/MW cost. Usually offset by increased transmission capacity About 40% more capacity compared to a bipole using the same 3-conductor system High redundancy: Loss of a converter or pole position drops just 16% of power at peak load

16. 16 © 2007 Electric Power Research Institute, Inc. All rights reserved. 2007 Planned Activity - Tools for Assessing Conversion of AC Power Transmission Lines to Tripole DC Transmission Phase I Objective - Feasibility Assessment Tools -An assessment of alternative dc configurations and system benefits. -Procedures, technical background and software references sufficient to assess conversion of specific ac transmission structures to dc -Guidance in the logistics of AC to DC conversion Phase II - Applications Studies -Assessment of ac to dc adaptation of existing transmission structures, including maximum dc voltage -System load flow and dynamic solutions, including modeling of detailed dc characteristics associated with various dc options -Cost/benefit analysis associated with conversion alternatives including comparison with ac flow enhancement measures Phase III - AC to DC Conversion Assessment Software -Software tool for AC/Tripole DC Transmission Conversion

17. 17 © 2007 Electric Power Research Institute, Inc. All rights reserved. Challenges (Cost of Converter-based Transmission Controllers!) Cost Breakdown (25%) 20 50

18. 18 © 2007 Electric Power Research Institute, Inc. All rights reserved. ETO- Technical Characteristics 5000A Snubber-less Turn-off Capability5000A Snubber-less Turn-off Capability Low Switching losses & Conduction losses Low Switching losses & Conduction losses Low Cost Device and Circuit Low Cost Device and Circuit Easy for Series and Parallel Operation Easy for Series and Parallel Operation Low Gate Drive Power Low Gate Drive Power Built-in Over-Current Protection and Current SensorBuilt-in Over-Current Protection and Current Sensor Easy for Mass-Production Easy for Mass-Production

19. 19 © 2007 Electric Power Research Institute, Inc. All rights reserved. Field Demonstration of ETO-Based STATCOM 5-10 MVA ETO-Based STATCOM for Condon Windfarm –Currently funded by BPA, TVA and TriState G&T Current Objectives Field demonstration of ETO- based STATCOM, technically and economically, in mitigating voltage fluctuation due to a wind-driven induction generator

20. 20 © 2007 Electric Power Research Institute, Inc. All rights reserved. FACTS Technology- Information and Knowledge Sharing Annual meeting, 9 th FACTS Users Group meeting Reference Book, EPRI Power Electronics-Based Transmission Controllers Reference Book (“The Gold Book”) EPRIFACTS.Com

21. 21 © 2007 Electric Power Research Institute, Inc. All rights reserved. 9 th FACTS Users Group Meeting Annual meeting Session A: Hydro Quebec’s Variable Frequency Transformer (VFT) Session B: FACTS Controllers, Applications and Operating Experience Session C: Power Electronics-Based Controllers, New Project Opportunities Session D: Power Electronics-Based Controllers, Technology Development Session E: Manufacturers Panel session

22. 22 © 2007 Electric Power Research Institute, Inc. All rights reserved. EPRI Power Electronics-Based Transmission Controllers Reference Book The objectives of this book are to: provide the utility members with historical perspectives basic design considerations factory testing, site installations, commissioning operating performance, operation and maintenance, and future trends

23. 23 © 2007 Electric Power Research Institute, Inc. All rights reserved. EPRI Power Electronics-Based Transmission Controllers Reference Book Written Chapters (five) Alternating Current (AC) Transmission Systems Power Semiconductors and Valves Generalized AC Transmission Controllers: Unified Power Flow Controller and Interline Power Flow Controller Voltage Sourced Converter-Based DC Transmission AC to Tripole DC Transmission Conversion Ten more Chapters to be written

24. 24 © 2007 Electric Power Research Institute, Inc. All rights reserved. THANKS FOR YOUR ATTENTION Questions? Together…..Shaping the Future of Electricity