Javad Morsali - Tabriz University
Rasool Kazemzadeh - Sahand University of Technology
Mohammad Reza Azizian

This paper proposes novel robust coordinated design of multi-input power system stabilizer MPSS and TCSCbased power oscillation damping (POD) controller to improvepower system small-signal stability. Although the coordinated design of CPSS-POD controller improves power system dampingcharacteristics, 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 concentratedon simultaneous tuning of adjustable gains and time constants of controllers. PSO algorithm tries to minimize an eigenvalue-basedmulti-objective function in which some loading conditions are considered concurrently to ensure robust design. From viewpointof 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 overvarious perturbations shows that superior enhancement in damping of power system oscillations has been obtained byutilizing proposed (P-W-Q) PSS-POD coordinated controllers in comparison with the CPSS-POD

P-W-Q) PSS; POD controller; coordinated controllers; PSO; power system stability enhancement