Θ-PSO Algorithm for UPFC Based Output Feedback Damping Controller

A novel approach based θ-Particle Swarm Optimization (θ-PSO) is proposed for optimal selection of the output feedback damping controller parameters for unified power flow controller (UPFC) in order to improve the damping of power system oscillations. The selection of the output feedback gains for the damping controllers is converted to an optimization problem with the time domain-based objective function which is solved by the θPSO algorithm. For designing, only local and available state variables are selected as the input stabilizing signals of each controller. Thus, structure of the proposed output feedback controller is simple and easy to implement. To ensure the robustness of the designed controllers, the design process takes into account a wide range of operating conditions and system configurations. Simulation results demonstrate that UPFC with the proposed output feedback controller can more effectively improve the dynamic stability, damp the oscillations, and enhance the transient stability of power system compared to the classical PSO and phase compensation based damping controllers. Moreover, the system performance analysis under different operating conditions shows that the δE based controller is superior to the mB based controller.