Coordinated design of MPSS and TCSC-based damping controller using PSO to enhance multi-machine power system stability

This paper proposes novel robust coordinated design of multi-input power system stabilizer MPSS and TCSC-based power oscillation damping (POD) controller to improve power system small-signal stability. Although the coordinated design of CPSS-POD controller improves power system damping characteristics, applying a high-potential MPSS such as (P-W-Q) PSS in coordination with the POD controller for the first time can take part more effectively in damping of electromechanical (EM) oscillations. The robust design problem is systematized as an optimization procedure and the coordination is concentrated on simultaneous tuning of adjustable gains and time constants of controllers. PSO algorithm tries to minimize an eigenvalue-based multi-objective function in which some loading conditions are considered concurrently to ensure robust design. From viewpoint of eigenvalue analysis, our suggested controllers try to shift the EM modes inside D-shaped target area specified by desired damping ratio and damping coefficient thresholds. Our time domain simulations in MATLAB/SIMULINK environment carried out on 2 area 4 machine (2A4M) power system over various perturbations shows that superior enhancement in damping of power system oscillations has been obtained by utilizing proposed (P-W-Q) PSS-POD coordinated controllers in comparison with the CPSS-POD.