Optimal parameter design of input filters for general purpose inverter based on genetic algorithm

Input filter design has attracted more and more attention in those conditions where harmonics and reactive power produced by the inverters will be injected into the power system during their operation when without any filter inserted. In this paper LC passive harmonic filters are employed with the advantages of cost-effective and reliability, compared with active power harmonic filters and PWM technique. Furthermore, for the facility to analyze inverter system with high accuracy, this paper proposes a more practical model suitable for all general purpose inverters at different power ratings, which is an equivalent current source containing major harmonics, paralleled with equivalent impedance. Finally, thanks to this equivalent system and the idea of genetic algorithm, this paper presents the optimum filter parameters to minimize current total harmonic distortion (THD). More importantly, those parameter values computed were proved to be practical by simulation results and industry applications.