COMPARISON OF FACTS DEVICES FOR TWO AREA POWER SYSTEM STABILITY ENHANCEMENT

Abstract

Transmission networks of modern power systems are becoming increasingly stressed because of growing demand and restrictions on building new lines. One of the consequences of such a stressed system is the threat of losing stability following a disturbance. Flexible ac transmission system (FACTS) devices are found to be very effective in a transmission network for better utilization of its existing facilities without sacrificing the desired stability margin. Flexible AC Transmission System (FACTS) such as Static Synchronous Compensator (STATCOM) and Static VAR Compensator (SVC), employ the latest technology of power electronic switching devices in electric power transmission systems to control voltage and power flow. A static synchronous compensator (STATCOM) and Static Var Compensator (SVC) is the shunt device of the flexible AC transmission systems (FACTS) family. When system voltage is low, STATCOM generates reactive power and when system voltage is high it absorbs reactive power where as the Static Var compensator provides the fast acting dynamic compensation in case of severe faults. In this Thesis, the performance of SVC is compared with the performance of STATCOM. Proposed controllers are implemented using MATLAB/SIMULINK. Simulation results indicate that the STATCOM controller installed with two machine systems provides better damping characteristics in rotor angle as compared to two machine system installed with SVC. Thus, transient stability enhancement of the two machine system installed with STATCOM is better than that installed with SVC.