Cascaded and Hybrid Multilevel Inverters with Reduced Number of Switches for Induction Motor

Abstract

In this paper, a modified hybrid multilevel inverter is introduced which employs bypass diode technique with H-bridge inverter topology. It aims to reduce number of controlled switches. The proposed inverter consists of a H-bridge and 3 unit cells. Each unit cell requires a serially connected voltage source and switch with a parallel diode. In a conventional multilevel inverter, presence of high number of switches increase the harmonics, switching losses, cost and total harmonics distortion. This proposed topology achieves fifteen level with only seven number of switches. It dramatically reduces complexity of control circuit, cost and low order harmonics and thus effectively reduces total harmonics distortion.