Comparison of SPWM technique and selective harmonic elimination using genetic algorithm

A comparison of sinusoidal pulse width modulation (SPWM) and selective harmonic elimination (SHE) in a multicell DC/AC converter is presented. The genetic algorithm finds the existence optimal solution set of switching angles for each required harmonic profile. The dc links of each full bridge cell are supplied by individual high frequency DC-DC isolation stages which are connected in parallel considering the dc input of the total system. Furthermore, the cells which are operated in an interleaved SPWM mode or SHE mode are connected in series, so that the desired output of a multilevel inverter is synthesized by the low voltage level output of each cell. Conclusions about the effectiveness of the proposed converter are supported by analysis and simulation results.