This paper presents a comparison study between a conventional and a fuzzylogic based power system stabiliser (PSS) to improve the stability of a synchronous generator. A conventional power system stabiliser (CPSS) is designed and simulated using MATLAB software package. Also a fuzzy logic based PSS (FLBPSS) is simulated. In the case of FLBPSS the stabilising signal is computed using a fuzzy membership function depending on the speedlacceleration state of the generator in the phase plane. The required measurement is the speed deviation over two samples. The simulation results are compared.