A novel three-phase seven-level inverter

Abstract

Recently, multilevel-inverters with less number of switching devices are becoming more popular due to compact size, reduced cost and higher efficiency. Though the multilevel inverter has significant advantages most of the recent works are addressed for single phase applications. Therefore, in this paper, a novel three-phase seven-level inverter is proposed with the inherent benefits of reduced switches and isolated DC sources. The proposed topology is developed with the combination of a three-level inverter and a full-bridge flying capacitor circuit for medium voltage applications. The three-level inverter part alleviates the undesired positive and negative spikes as generated by a conventional three-level inverter. The performance of the proposed seven-level inverter is studied for different modulation indices with RL load and their results are presented.