M.Mythili, N.Kayalvizhi
The Selective Harmonic Elimination (SHE) technique is the fundamental switching frequency scheme which is used to eliminate specific order harmonics. In this paper, the elimination of low order harmonics in cascaded multilevel inverter with equal DC sources is proposed. The modulation strategy used here is SHEPWM in which non linear equations that characterize the low order harmonics are obtained. The equations are solved using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) algorithm to obtain the switching angles which are used to eliminate the harmonics. Comparison of GA and PSO algorithms are done using MATLAB software to know the effectiveness of getting optimized switching angles.