Optimal Design Of Passive Power Filters Based On Modified PSO

Along with the development of science, technology and economy, the requirement of power quality from consumers becomes higher and higher. At the same time, due to the wide-range application of nonlinear load, harmonic pollution has brought many power quality problems. Therefore, passive power filter (PPF) is most widely used as harmonic limitation in power system, because of its simple configuration, low investment, high reliability, and low operation cost. It plays an important part in harmonic limitation and reactive power compensation. The research on optimal design of passive power filters has great value to popularize and high actual application.This paper analyses the configuration and working principle of PPF, summarizes the optimal design methods of PPF at present. Based on the factors which are related to the filter's characteristics, modified Particle Swarm Optimization (PSO) algorithm is used to design the passive power filter paramenters according to the characteristics of multi-objective optimal problems.PSO is a new swarm intelligence optimization technique. Based on analysis of the Standard Particle Swarm Optimization (SPSO) model, a new Extended Particle Swarm Optimization (EPSO) algorithm is proposed in this paper. By introducing increment PID operator and four more random factors in EPSO, the new algorithm improves individual and social cognition ability of particles, increases shared information, and makes the motion of particles more intelligent. Furthermore, swarm variety is improved by four more random factors, and then the global optimization has greatly improved. Vector-evaluated Particle Swarm Optimization (VEPSO) algorithm is used to achieve the goal of Multiple Objective (MO) optimal design. As to the social information sharing, by using the goal selected randomly of Vector-evaluated Genetic Algorithm (VEGA) proposed by Fourman and Kursawa for reference, VEGA is applied to assign social information of VEPSO algorithms.Based on multi-objective algorithm proposed in this paper, a new method of multi-objective optimal design of passive power filters is put forward. Harmonic elimination, economic indicator and reactive power compensation are considered comprehensively and its detailed realizing procedure is given. Simulation results show that superior performances of the EPSO algorithm that proposed in this paper are not easy to fall into local optimum and the convergence rate of EPSO is improved. As an expansion of SPSO algorithm, the EPSO is universal and can be used for solving all optimization problems where SPSO used; MO optimal design of PPF based on vector evaluated PSO algorithm can obtain good performance of harmonic elimination and reactive power compensation as well as satisfactory economic performance.