Power System Stability Enhancement by Enhancing the Performance of SVC

This paper presents the model of a static VAR compensator (SVC) which is controlled externally by a Proportional Integral Differential (PID) controller for the improvements of voltage stability and damping effect of an on line power system. The PID controller parameters have been selected by using Cohen-Coon open loop tuning rule method. Both single phase and three phase faults have been considered in the research.Phasorsimulation method has been used & Simulation result shows that the SVC with PID controller is more effective to enhance the voltage stability and increases power transmission capacity of a power system. It has been observed that the SVC ratings are only 40 MVA with PID and 200 MVA without PID. The damping was 0.01% with PID controller in compared to that of 0.5% without PID. For single line to ground fault, Using PID the system voltage, power(P,Q), speed deviation(dω) becomes stable in 1.5s,0.6s,0.7s & 2s and without PID controller 3.5s, 3s & 4.5s respectively. Similarly, For L-L faults, Using PID the system voltage, power(P,Q),speed deviation(dω) becomes stable in 1.4s, 0.6s, 0.7s & 2.5s and without PID controller system becomes stable in 5srespectively. So with PID controller the system performance is greatly enhanced. Index Terms—Static VAR Compansator (SVC), PID Controller, AVR, TCR, Voltage regulation, MATLAB Simulink.