The Power system is a Dynamic and highly integrated system and it is being continuously subjected to disturbances. The disturbances may be having frequency range of 0.2 to 3.0 Hz. These low frequency oscillations cause a loss of synchronism and eventual breakdown of the entire system. The used of PSS has become very common in operation of large electric power system. Power system stabilizer are used to generate supplementary control signal for the excitation system in order to damp the low frequency oscillation. The traditional solution of this problem is application of conventional Power system stabilizer. The CPSS which use Dynamic compensator where gain setting design for the specific operating conditions is giving poor performance under different loading condition. Therefor it is very difficult to design a stabilizer that could present good performance in all operating points of electric power system