OPTIMAL-TUNING OF PID POWER SYSTEM STABILIZER IN SIMULINK ENVIRONMENT FOR A SYNCHRONOUS MACHINE

In this paper, an optimum algorithm approach is presented for determining the optimal Proportional-Integral-Derivative (PID) Controller parameters of a typical power system stabilizer (PSS) in a single machine infinite bus system. The paper is modeled in the MATLAB Simulink Environment to analyze the performance of a synchronous machine under normal load conditions. The functional blocks of PID controller with PSS are generated and the simulation studies are conducted to observe the dynamic performance of the power system. This paper suggests the use of Ziegler-Nichols method to form the intervals for the controller parameters in which the tuning to be done. In order to assist the estimation of the performance of the proposed PID-PSS controller, a time-domain performance criterion function has been used. The proposed approach yields better solution in term of rise time, settling time, and maximum overshoot of the system. Analysis in this paper reveals that the Ziegler-Nichols method of optimal tuning PID controller gives better dynamic performance as compared to that of conventional trial and error method. Simulation results indicate that the performance of the PID controlled system can be significantly improved by the ZieglerNichols-based method.