Small Signal Stability Improvement and Congestion Management Using PSO Based TCSC Controller

In this paper an attempt has been made to study the application of Thyristor Controlled Series Capacitor (TCSC) to mitigate small signal stability problem in addition to congestion management of a heavily loaded line in a multimachine power system. The Flexible AC Transmission System (FACTS) devices such as TCSC can be used to control the power flows in the network and can help in improvement of small signal stability aspect. It can also provide relief to congestion in the heavily loaded line. However, the performance of any FACTS device highly depends upon its parameters and placement at suitable locations in the power network. In this paper, Particle Swarm Optimization (PSO) method has been used for determining the optimal locations and parameters of the TCSC controller in order to damp small signal oscillations. Transmission Line Flow (TLF) Sensitivity method has been used for curtailment of non-firm load to limit power flow congestion. The results of simulation reveals that TCSC controllers, placed optimally, not only mitigate small signal oscillations but they can also alleviate line flow congestion effectively. Keywords—Congestion management, Particle Swarm Optimization, Small Signal Stability, Thyristor Controlled Series Compensator, Transmission Line Flow Sensitivity.