English title

In this paper, design of optimal control for the UPFC controllers including power-flow, DC voltage regulator and generator terminals voltage controller are presented. The controllers were designed based on GA optimization method for linearized modified Phillips Heffron model of SMIB in state space form. For nominal operating condition, the eigen-values of the system were obtained which clearly indicated the system was unstable. Therefore a damping controller was designed based on lead-lag compensation to improve the stability. After achieving the required stability, the power-flow, DC voltage regulator and generator terminals voltage controller were designed. Validity of the proposed method was confirmed by time domain simulation results.