Total Harmonic Distortion Reduction of a Multilevel Inverter Voltage byA Combined Continues GA-PSO

Multilevel inverters are increasingly employed in the structures of fuel cells, solar cells and wind turbines. So, techniques to cope with total harmonic distortions (THDs) in multilevel inverters should be regarded. Mathematical approaches to suppress the harmonic distortions have already been reported in the literatures. However, these approaches are not sufficient for high level inverters. In this research, a combined continues genetic algorithm (CGA) and particle swarm optimization (PSO) method is employed to multilevels in order to define optimal switching angles for cascaded multilevel inverters, eliminating some higher-order harmonics while maintaining the main order. This technique can be utilized for multilevel inverters with a desired number of levels. Here, two algorithms are employed to optimize THDs in multilevel inverters: CGA and PSO. They are applied on ۷th and ۱۱th level inverter and the theoretical and simulated results are compared to validate the efficacy of the proposed method. In addition, this work presents a method for optimizing the specific harmonics and improving the switching characteristics in the same level inverters.

کلیدواژه ها:

Multilevel inverter ، continues genetic algorithm ، particle swarm optimization ، total harmonic distortion