Selective Harmonics Elimination of Multi Level Inverters via Methods of GPS, SA and GA

One of the major problems in electric power quality is the harmonic contents. This paper focuses on elimination (reduction) of harmonics in a H-bridge multi-level voltage-source inverter. Here the basic concept is to eliminate specific harmonics with a proper choice of switching angles. This technique is very efficient for improving the multi-level inverter output voltage quality. In This paper, Generalized Pattern Search (GPS), Simulated Annealing (SA) and Genetic Algorithm (GA) are used to achieve proper switching angles. The proposed methods can be applied to all of the multi-level inverters. The main purpose is to eliminate some low order harmonics and to maintain the fundamental components at the desired values. As a case study, The proposed methods are applied and tested on a 13 level inverter These results show the higher effectiveness and faster speed of generalized pattern search in comparison with SA and GA.