Implementation of a three-phase multilevel boosting inverter using switched-capacitor converter cells

Abstract

Manufacturers of power electronic converters seek to increase not only power and voltage ratings but also power density. Inductorless converters help achieve the latter because capacitive energy storage has higher energy density than inductive energy storage. Multilevel topologies, which include some inductorless topologies, enable converters to operate at higher voltage levels by allowing voltage sharing between devices. This paper presents a novel multilevel inductorless boosting three-phase inverter that is constructed using a series configuration of switched-capacitor converter cells. This allows for the inverter to be used without an additional boost converter or output transformer when powered from a low-voltage dc source, such as the battery of a grid-connected energy storage system or an electric vehicle.