Swarm and bacterial foraging based optimal power system stabilizer for stability improvement

This paper presents a robust power system stabilizer (PSS) based PID controller for study of stability in a single-machine-infinite-bus (SMIB) power system. The PID controller gains are optimized by bacterial foraging optimization (BFO) and particle swarm optimization (PSO) for improvement of system stability in SMIB system. The robustness of the controller was tested under different operating conditions and their performances are being compared with the conventional PSS-PID controller. In addition, their effectiveness are also investigated through the performance indices like Integral Squared Error (ISE), peak overshoot and settling time. Further, stability of the power system is evaluated by bode plot and mean squared error curve of the proposed optimization techniques. It is observed from the simulated results that PSO based PSS-PID controller provide better performance and stability as compared to BFO optimized PSS-PID and conventional PSS-PID controllers under different operating scenarios.