Decentralized tap changer blocking and load shedding against voltage instability: prospective tests on the RTE system

This paper reports on prospective tests of a system protection scheme against long-term voltage instability relying on a set of distributed controllers, each monitoring a transmission voltage, blocking tap changers and shedding loads in a zone. The emergency actions adjust in magnitude and location to the disturbance. Each controller acts in closed-loop, which guarantees robustness. The method is illustrated on a real-life model of the Western region of the RTE system. The choice of the controller settings is discussed in some detail and examples of performance are given, combining the above remedial action with capacitor switching and secondary voltage control.

[1]  J. Y. Leost,et al.  Survey of the Secondary Voltage Control in France : Present Realization and Investigations , 1987, IEEE Transactions on Power Systems.

[2]  W. Concepts of Undervoltage Load Shedding for Voltage Stability , 2004 .

[3]  T. Van Cutsem,et al.  Reverse-logic control of load tap changers in emergency voltage conditions , 2003, 2003 IEEE Bologna Power Tech Conference Proceedings,.

[4]  Thierry Van Cutsem,et al.  Voltage Stability of Electric Power Systems , 1998 .

[5]  C. Moors,et al.  Design of an undervoltage load shedding scheme for the Hydro-Quebec system , 2003, 2003 IEEE Power Engineering Society General Meeting (IEEE Cat. No.03CH37491).

[6]  Peter Crossley,et al.  System Protection Schemes in Power Networks , 2001 .

[7]  C.D. Vournas,et al.  Comparison and combination of emergency control methods for voltage stability , 2004, IEEE Power Engineering Society General Meeting, 2004..

[8]  T. Van Cutsem,et al.  Undervoltage Load Shedding Using Distributed Controllers , 2007, IEEE Transactions on Power Systems.

[9]  S. Imai Undervoltage load shedding improving security as reasonable measure for extreme contingencies , 2005, IEEE Power Engineering Society General Meeting, 2005.

[10]  G. Moreschini,et al.  Coordination and control of tap changers under load at different voltage level transformers , 1996, Proceedings of 8th Mediterranean Electrotechnical Conference on Industrial Applications in Power Systems, Computer Science and Telecommunications (MELECON 96).