Design of GWO optimized dual UPFC controller for damping of power system oscillations

This paper proposes the design of an optimized dual UPFC controller for damping power system oscillations, where modulation index of series converter and phase angle of shunt converter voltage are controlled simultaneously. The dual damping controller parameters are optimized by a recently reported metaheuristic optimization technique known as Grey Wolf Optimizer (GWO). This is a simple technique which can effectively optimise all the six parameters of the controller. The effectiveness of this proposed optimized dual controller is compared with PSO optimized dual controller and single independent GWO and PSO optimized controllers. The dynamic responses of speed deviation for all the controllers are considered for a step change in mechanical input power considering a single machine infinite bus system. Eigen value analysis of the system are performed and it has been observed that the performance of proposed optimised dual controller is much better in damping of low frequency oscillations as compared to others in terms of settling time, peaks of oscillations and convergence rate, thus enhancing dynamic stability to a large extent.