On the Effect of TCSC and TCSC-Controller Gain on Bifurcations of Subsynchronous Resonance in Power Systems

Abstract

The effect of thyristor-controlled series capacitor (TCSC) and its controller gain on bifurcations of subsynchronous resonance (SSR) in power system are studied. Single machine infinite bus (SMIB) power system is considered for the numerical investigations. The series compensation of the transmission line is done by either conventional variable series capacitor or TCSC . The effect of the dynamics of the damper windings is investigated. The results show that in all cases, the operating point of the system loses stability via Hopf bifurcation. Hopf bifurcation comes either in subcritical or supercritical type. Supercritical Hopf bifurcation is depicted when the dynamics of the damper windings are neglected and the line is compensated by conventional series capacitor. With the same compensation scheme i.e., conventional series capacitor, supercritical Hopf bifurcation is addressed when the dynamics of the damper windings are included. On the other hand, subcritical Hopf bifurcation is predicted when the compensation is carried out by TCSC for both cases of including and neglecting the dynamics of the damper windings. In case of supercritical Hopf bifurcation, the system routes to chaos via torus breakdown. Additionally, it is found that when the compensation is done by TCSC, the stable operating point region is enlarged. Moreover, the stable operating point region increases when the damper windings are neglected. The effect of the TCSC controller gain on the locations of the Hopf bifurcation has also been studied.

Key Words:

• Bifurcation theory and chaos
• subsynchronous resonance
• thyristor controlled series capacitor
• damper windings

Additional information

Notes on contributors

M.S. Widyan

MohammadS.Widyan was born on December 05, 1976 in Irbid, Jordan. He received his B.Sc. degree in Electrical Power Engineering from Yarmouk University, Jordan in 2000. His M.Sc. degree in Control and Power Engineering was from Jordan University of Science and Technology in 2002. From 2002 to 2003 he worked as a Lecturer in Electrical Engineering Departmentat The Hashemite University, Jordan. The Ph.D. was from the University of Technology Berlin, Germany in 2006. Currently he is an assistant professor in Electrical Engineering Department at The Hashemite University. His fields of interest are permanent-magnetand conventional electrical machines de-sign, finite-element technique, power system and electrical machines dynamics, subsynchronous resonance, bifurcation theory and control.

A.M. Harb

Ahmad M. Harb was born in Irbid, Jordan, in 1963. He received his Ph.D. degree from Virginia Polytechnic Institute and State University, Blacksburg, VA, in 1996, his M.S. degree from the Jordan University of Science and Technology, Irbid, Jordan, in 1990, and his B.S. degree from Yarmouk University, Irbid, Jordan in 1987, all in electrical engineering. Currently, he is an associative professor at Jordan University of Science and Technology in the Electrical Engineering Department. He was a visiting professor at Virginia Tech., Blacksburg, VA, in 1997 and at Oakland University, Rochester, MI, in 2001. He received National Science Foundation (NSF) funded projects jointly with the University of Central Florida, Orlando. He is a visiting professor at University of Central Florida, Orlando. His research interests include power system analysis and control, modern nonlinear theory (bifurcation and chaos), linear systems, power system planning, electric machines, optimal control and power electronics. He is an associative editor of two International Journals, the International Journal of Modeling and Simulation and the International Journal of Power and Energy Systems. He is the chair conference of Modern Nonlinear Theory, Montreal—Canada, May 30—June 1, 2007 and Orlando-USA, November 16–18, 2008.