Abstract: In this paper, a robust supplementary controller of thyristor-controlled phase shifter(TCPS) using control theory has been designed to damp power system oscillation and to enhance power system stability despite uncertainties of the power systems. Since an order of a designed controller using control theory become very high, a structure-specified low-order TCPS controller using genetic algorithm (GA) has been designed. In order to treat disturbance attenuation and robust stability specifications simultaneously in the stage of controller design using GA, two weighting transfer functions have been selected. The norm and damping ratio have been used as the objective function in GA. To verify control performance of proposed TCPS controller, the modal analysis and nonlinear simulations for one-machine infinite bus system have been performed. The simulation results under various disturbances for various operating conditions showthat the proposed TCPS controller provided better dynamic responses in comparison with the conventional PSS and TCPS controller.
Keywords: Thyristor-controlled phase shifter (TCPS), control theory, genetic algorithm (GA), robust control, power system stabilizer (PSS).