Damping of Low Frequency Oscillations using Robust PSS and TCSC Controllers

This paper deals with thorough study of the Linearized State Space Model of Single Machine Infinite Bus (SMIB) System installed with Thyristor Controlled Series Capacitor (TCSC). The effect of loading condition and the reactance of TCSC on the system coefficients i.e. constants, K's, involved in the linearized state space model has been plotted and investigated. Robust Power System Stabilizer (PSS) and Robust TCSC controllers have been designed, using H-infinity loop shaping technique, and hence, proposed for an SMIB system. Voltage and Angular Stability of the SMIB system with or without using the proposed controllers have been analyzed. The simulation studies show that the proposed controllers effectively damp out the system's low frequency oscillations, when subjected to perturbation in terms of deviation in per unit (pu) electrical power.