Damping the local and the inter-area power oscillations of a multi-machine power system using a fuzzy stabilizer

Power system is a nonlinear time-variant system with a large variety of disturbances among them is the Low Frequency Oscillations (LFO). It is necessary to have an appropriate Power System Stabilizer (PSS) which can stabilize the power system in different operating points. In this paper fuzzy logic has been used to design the stabilizer for a multi-machine power system. The main advantage of fuzzy logic is that a person can involve the experiences he has about the system’s behavior, in the design process. These experiences are implemented as fuzzy rules. In this paper a fuzzy PSS is designed to stabilize a typical two-area four-machine power system under a short-term 3 phase short circuit fault. Results show the advantages of the proposed stabilizer over the classic one in damping the local and inter-area oscillations.