A Single Phase Five Level Inverter based on switched DC sources with Reduced Number of Total Component Count by Novel Topology

Abstract

A Single Phase Multilevel Inverter is designed to reduce the number of power switch requirement and gate drive circuit. So, it reduces total component count in the circuit than other conventional converters for the same level. In this topology, two DC supply and six switches are used to get five level output. In case of Cascaded H-Bridge Inverter, two DC sources and eight Power switches are required for getting five level. A multilevel voltage-source inverters are the unique solution for high power dc-to-ac conversion applications. A multilevel inverter is a linkage structure of multiple input dc levels and power semiconductor devices to get a quasisquare or staircase waveform. In addition, the multilevel waveform has a less harmonic contents as compared to a two-level waveform obtained from conventional inverters. The quality of the multilevel waveform is improved by increasing the number of levels. But, If number of level increases, a large number of power semiconductor devices and gate driver circuits are also increased. So, it will increases system complexity , cost and it will reduces the system reliability and efficiency. So, it is necessary to reduce the number of switches and gate driver circuits by using new topology. This paper presents a single phase five level inverter that has reduced total component count. It consists two step down transformer and two bridge rectifier to provide DC voltage to inverter circuit. This Inverter topology is mainly divided in three parts namely control circuit, gate drive circuit and power circuit. These all the circuits are explained in this paper. The topology is investigated through simulations and validated experimentally on a laboratory prototype.