Robust TCSC controller for POD considering global signal and load composition uncertainties

This paper presents robust controller design for damping of inter-area mode oscillations in two area test system by Thyristor Controlled Series Capacitor (TCSC) using global signal. The stabilizing signal is obtained from phasor measurement units (PMUs) located in both areas of test power system. Residue analysis is carried out to decide the best control signals for damping of critical mode. H_∞ loop shaping technique is used to design the damping controller. The uncertainties present in load model composition may result in over/under estimation of damping capability of the designed controller. Various load models representing different composition of static loads are considered for checking the robustness of the designed controller for worst case load scenarios. Robustness of the designed controller is assessed in frequency domain and via non linear time domain simulations for various contingent conditions. The performance of the designed controller is found satisfactory in damping critical mode oscillation under various critical operating conditions.