Simultaneous stabilization of power systems equipped with unified power flow controller using particle swarm

In this paper, the use of the supplementary controller of a unified power flow controller (UPFC) to damp low frequency oscillations in a weakly connected system is investigated. The potential of the UPFC supplementary controllers to enhance the dynamic stability is evaluated by measuring the electromechanical (EM) controllability through singular value decomposition (SVD) analysis. Individual designs of UPFC controllers using particle swarm optimization (PSO) technique are discussed. To ensure the robustness of the proposed stabilizers, the design process takes into account a wide range of operating conditions. The effectiveness of the proposed controllers in damping low frequency oscillations is verified through eigenvalue analysis and non-linear time simulation. A comparison with a robust power system stabilizer is also included.