Optimal Design of UPFC Output Feed Back Controller for Power System Stability Enhancement by Hybrid PSO and GSA

In this paper, the optimal design of supplementary controller parameters of a unified powerflow controller(UPFC) for damping low-frequency oscillations in a weakly connected systemis investigated. The individual design of the UPFC controller, using hybrid particle swarmoptimization and gravitational search algorithm (PSOGSA)technique under 3 loadingoperating conditions, is discussed. The effectiveness of proposed controller on enhancingdynamic stability is tested through eigenvalue analysis and time domain simulation. Alsononlinear and electrical simulation results show the validity and effectiveness of theproposed control schemes over a wide range of loading conditions. It is also observed that theproposed UPFC-based damping stabilizers greatly enhance the power system transientstability. Also, simulation results of coordinated design of stabilizer based on δE and mB ispresented and discussed,the system performance analysis under different operating conditionsshow that the δE-based controller is superior to the mB-based controller.