Selective harmonic eliminated pulse width modulation (SHE-PWM) method using genetic algorithm in single-phase multilevel inverters

Abstract

Numerous techniques have been used in the literature to produce switching signals in multilevel inverters (MLIs). Reducing the number of switching component in multilevel inverters is another area of interest in the literature. In this paper, a MLI with low switching number has been designed and worked successfully in harmonic elimination method. For this purpose, a novel genetic algorithm based SHE-PWM in a single phase 11-level inverter is presented in order to eliminate the switching signals. Also, total harmonic distortion (THD) analysis, which depends on switching angles for multilevel inverters, in a wide modulation range of 11-level inverter topology is presented. Hence, the switching angles are first estimated by Genetic Algorithm (GA) method, in which a certain number of harmonic components are eliminated. THD analysis is performed using both analytical and MATLAB simulation using calculated switching angles. The proposed method is applied to an 11-level inverter to eliminate 3th, 5th, 7th and 9th harmonic content in the range of modulation index 1.5 and 4. A simulink model which provides simulating and validating the accuracy, dynamics and continuity of the GA solution, was created. Experimental validation is not carried out in this study. Considering the simulation results and similar studies in the literature, the success of the reduced inverter topology and GA supported harmonic elimination technique was observed.