PID Type Stabilizer Design for Multi Machine Power System Using IPSO Procedure

This paper presents a modified Iteration Particle Swarm Optimization (IPSO) algorithm to tune optimal gains of a Proportional Integral Derivative (PID) type multiple stabilizers and non-smooth nonlinear parameters (such as saturation limits) for multi machine power system, simultaneously. The problem of robustly tuning of PID based multiple stabilizer design is formulated as an optimization problem according to the time domain-based objective function which is solved by a modified strategy of PSO algorithm called IPSO technique that has a strong ability to find the most optimistic results. In the proposed algorithm, a new index named, Iteration Best, is incorporated in standard Particle Swarm Optimization (PSO) to enrich the searching behavior, solution quality and to avoid being trapped into local optimum. To demonstrate the effectiveness and robustness of the proposed stabilizers, the design process takes a wide range of operating conditions and system configuration into account. The effectiveness of the proposed stabilizer is demonstrated through nonlinear simulation studies and some performance indices on a fourmachine two areas power system in comparison with the classical PSO and PSO with Time-Varying Acceleration Coefficients (PSO-TVAC) based optimized PID type stabilizers. The results of these studies show that the proposed IPSO based optimized PID type stabilizers have an excellent capability in damping power system inter-area oscillations and enhance greatly the dynamic stability of the power system for a wide range of loading condition. Also, it is superior that of the PSO and PSO-TVAC based tuned stabilizers in terms of accurateness, convergence and computational effort.