Impact of Power System Stabilizer on Combined ALFC and AVR System

Abstract

This study demonstrates the impact of Power System Stabilizer (PSS) on the combined Automatic Load Frequency Control (ALFC) and Automatic Voltage Regulator (AVR) model of two unequal area systems. Both areas of the system have wind, diesel, and reheat thermal plant with proper physical constraints. Fractional-order PIλDF controller is introduced for the system and the performance of the same is compared with some integer-order controllers. The parameters of controllers and PSS are optimized simultaneously using lightning search algorithm. The investigation indicates the superior performance of PIλDF to others. The impact of PSS on system dynamic performance is investigated and infers that the inclusion of PSS damps out the system oscillations, which consequently enhances the system dynamic performance. Also, robust performance of the PIλDF controller and PSS parameters for the considered system are established against changing parameters of generator field.