GA optimized weighted random pulse width modulation approach for the elimination of harmonic distortion for multilevel inverters

Abstract

This paper proposes an optimized weighted random pulse width modulation (WRPWM) scheme for multilevel power converters, for the elimination of harmonic distortion present at the output of the converter. In weighted random pulse width modulation, the PWM signal is generated by comparing random binary numbers with the fundamental reference signal. The proposed optimized WRPWM strategy provides an improved performance over traditional random pulse width modulation schemes for multilevel inverters. A binary valued Genetic algorithm (GA) is employed for the optimization process. The total harmonic distortion (THD) is taken as the performance index for optimization. Simulation results of optimized WRPWM scheme for a three-level and five-level inverters are presented in this paper.