Implementation of a Five-Level inverter using Reverse Voltage Topology: A Competitive Solution for High-Power IM Drive Applications

Abstract

Multi-level inverter technology has emerged recently as a very important alternative in the area of highpower high-voltage energy control. So multi-level inverters have been widely used for high-power high-voltage drive applications. Due to higher number of sources, lower EMI, lower % THD in output voltage and less stress on insulation, they are widely used. However, it has some disadvantages as complicated PWM controlling method, increased number of components and voltage balancing problem at neutral point. In this paper a new topology called Reverse Voltage is proposed to improve multi-level performance by compensating the disadvantages just mentioned. This topology requires fewer components compared to available multi-level inverters (especially in higher levels) and requires less carrier signals and does not need separate mechanism for balancing of the capacitor voltages. Proposed induction motor drive structure offers reduced device count, simple power-bus structure when compared to a conventional five-level NPC and flying capacitor inverter fed induction motor drives. The topology and the control method based on SPWM are shown and the required components are also compared to other topologies to show the superiority of the topology. Finally simulation and experimental results on different types of loads are presented and discussed.