Performance evaluation of multi machine power system with Fuzzy based Power System Stabilizer

Power system operates under secure state. Any disturbance in terms of fault or major load change introduces oscillations in the power system. These oscillations cause stability problems, if not damped in short span of time. In a multi machine power system the rotor swing between generators makes the problem more complicated. In this paper Fuzzy Logic based Power System Stabilizer (FLPSS) is designed to damp the low frequency oscillations arising out of small and large disturbances in multi machine system. FLPSS is designed with speed deviation and rotor acceleration as input signals. The novelty about the work reported in this paper is that nine linguistic variables are considered to design the FLPSS. A four machine, two-area system is considered to validate the design of the proposed FLPSS. The superiority of the FLPSS is demonstrated by comparing its performance with that of a Conventional PSS (CPSS) by carrying out nonlinear simulation on the multi machine.