A new switched DC –link capacitor based multilevel converter (SDC2MLC)

Abstract

At present, one of the most common techniques for high power conversion in medium voltage applications is the use of cascaded multilevel converters. In this article, a new Switched DC-Link Capacitor Multilevel converter (SDC2MLC) with considerably few numbers of power electronics switches (IGBTs) is proposed, where keeping the total harmonic distortion (THD) of the output voltage waveforms as low as possible is desired. The proposed topology is configured using two separate basic units. Each unit consists of four switches with a series-parallel combination of isolated DC sources. The performance of the presented topology for both configurations is described. The required number of switches, power diodes, gate driver circuits and voltage stresses across the switches are compared with those of other recent published techniques. Furthermore, operation and performance of the proposed SDC2MLC are illustrated with the aid of experimental results of a single-phase 11-level converter to clarify the viability of the proposed topology.