Low order harmonics elimination in multilevel inverters using fuzzy logic controller considering the variations of dc voltage sources

The voltage variations are inevitable in most kind of dc sources used in multilevel inverters. Therefore, using the selective harmonics elimination (SHE) techniques to eliminate low order harmonics considering specific combination of constant voltage sources seem to be impractical or less usage. In this paper, by employment of fuzzy logic controller, a suitable control method for elimination the low order harmonics and achieving the desired fundamental output voltage for a wide range of dc voltage sources variations is proposed. The simulation results on a 7-level cascaded inverter are presented to confirm the correctness of the proposed control method.