Optimum SHEPWM for a new 21-level inverter topology using numerical optimization methods: experimental comparative study

Abstract

This article presents the application of the harmony search (HS) optimization algorithm for harmonic elimination in a new topology of multilevel inverters with a reduced number of electronic switching elements. The main objective of the harmonic elimination strategy is eliminating undesired low rank harmonics in order to improve the quality of the output waveform. The harmonic elimination strategy is achieved by solving a system of nonlinear equations. In this paper, HS optimization is applied using artificial neural networks (ANNs) on a new 21-level inverter topology. The algorithm is based on the music improvisation process. MATLAB programming software was used to develop a HS optimization program for harmonic elimination. The main reason for using selective harmonic elimination based on ANNs in this study is to control the proposed multilevel inverter in real-time. In order to assess the performance of the proposed optimization method, it was compared to particle swarm optimization and the genetic algorithm. A small-scale laboratory of the proposed 21-level inverter is built to validate the simulation results and to prove the efficiency of the proposed control scheme.