An Adaptive Fuzzy-Logic Stabilizer for Single and Multi-Machine Power Systems

This paper introduces a fuzzy controller as a power system stabilizer used to damp inter-area modes of oscillation following disturbances in power system. The fuzzy-logic power system stabilizer (FPSS) has been designed to provide a supplementary signal to the excitation system of the synchronous generator. The performance of FPSS, which is tuned automatically as the operating conditions of power system change, is investigated by applying it to a single machine and multi-machine including four machines in two areas of power system. Three proposed types of fuzzy control algorithms are reviewed and tested in these cases, for various types of disturbance. To show the effectiveness of the proposed controller in damping oscillations a three-phase short circuit condition under various loading conditions is presented to illustrate the application of the developed methodology. The obtained results show that the proposed controller for stabilizing power system can provide very good damping characteristic, in comparison with the conventional PSS, through wide range of operating condition for power system and improves dynamic operating of the system substantially.