Power System Stabilizer Tuning by Incorporating WECC Criterion into Particle Swarm Optimization

Implementation of a high gain and fast response excitation system to improve transient stability can adversely affect the system damping capability caused by negative damping. Therefore, power system stabilizer (PSS) is introduced to enhance the dynamic performance in regard to damping capability. This paper investigates the methodology for tuning the PSS. Apart from manual PSS tuning method, one tuning method is the particle swarm optimization (PSO) which is basically used to optimize the eigenvalue-based objective functions. However, this method does not automatically guarantee the Western Electricity Coordinating Council (WECC) criterion compliance for phase compensation at different operating conditions. Thus, a second tuning method is proposed by incorporating the WECC criterion into the original objective function of PSO. The results are illustrated using a practical hydro power plant in Bhutan. The result comparison between the original PSO tuning method against the proposed tuning method is presented in a form of bode plots, eigenvalues and the time-domain simulation.