Selective harmonic elimination for cascaded multilevel inverters using Grey Wolf Optimizer algorithm

In this paper, Grey Wolf Optimizer (GWO) algorithm is applied to determine optimum switching angles for cascaded multilevel inverter of eliminating some high order harmonics while maintaining the required fundamental voltage. As case study in this paper, 11-level and 15-level inverter are considered and the optimum switching angles are calculated off-line to eliminate the 5th, 7th, 11th, 13th harmonics for the 11-level as well as 17th, 19th harmonics for 15-level. The total harmonic distortion is used to estimate the quality of output voltages. The results are shown graphically for better understanding, the mathematical formulations and simulation results will be presented.