Studying PI Self-Tuning Controller with Variable Parameters for Unified Power Flow Control Based on Particle Swarm Optimization

In view that the traditional PI regulators used for the series side of the unified power flow controller(UPFC) suffers from a wide range of system operating conditions, its control performance is poor and it is difficult to achieve ideal control effect. A PI self-tuning controller with variable parameters based on particle swarm optimization algorithm(PSO) is proposed in this paper. A model of single machine infinite bus power system is founded by using Matlab/Simulink. The proposed control strategy is compared with the traditional PI control strategy. Simulation results show that the proposed control method has stronger tracking ability of power flow, and can effectively reduce the power oscillation caused by the three-phase short-circuit fault, reduce the fluctuation of generator speed and improve the system damping and transient stability.