A PSO Procedure for a Coordinated Tuning of Power System Stabilizers for Multiple Operating Conditions

The problem of coordinated tuning stabilizers in multi-machine power systems is formulated here as a sequence ofoptimization problems. The design problem of stabilizers is converted to a nonlinear optimization problem with a multiobjectivefitness function. The proposed method employs particle swarm optimization (PSO), an algorithm to searchfor optimal parameter settings of a widely used conventional fixed-structure lead-lag power system stabilizers(CPSSs). One of the main advantages of the proposed approach is its robustness to the initial parameter settings. Inaddition, the quality of the optimal solution does not rely on the initial guess. The robustness and performance of thenewly designed controllers is evaluated in a large sixteen-machine power system subjected to different loadingconditions in comparison with the genetic algorithm (GA) based PSSs design. The superiority of the controllerdesigned is demonstrated through the nonlinear time-domain simulation and some performance indices studies. Theresults analysis reveals that the tuned PSSs with proposed objective function has an excellent capability in dampingpower system low-frequency oscillations.