27-Level Converter for Electric Vehicles Using Only One Power Supply

Abstract

Multilevel inverters need a large amount of floating power supplies (batteries) to operate, which is unsuitable for electric vehicles. In this work, a very simple scheme, based on a small high frequency link (HFL), allows the utilization of only one battery pack for the complete multilevel drive. For example, a 27-level converter normally needs nine isolated power supplies and the proposed system reduces these nine sources to only one: the battery car. The topology also permits full regenerative braking. Simulations and experimental results show the feasibility to implement this “one-source” multilevel system.