Multilevel Inverter Topologies and Modulation Techniques for Grid Connection of Renewable Energy Source

Abstract

Multilevel inverters (MLI) with non conventional energy source or renewable energy source such as solar photovoltaic (PV) or wind for grid power generation is day by day becoming more & more popular. Therefore more attention is paid by the researchers on multilevel inverters as a power conversion medium between renewable energy source and grid. For medium and high power applications such as grid connection of renewable energy source, multilevel inverters are widely accepted power converters due to their advantages over conventional inverters. Multilevel inverters are also used in Uninterrupted Power Supply (UPS), three phase induction motor drive, etc. There are different multilevel inverter topologies and different modulation techniques developed and still researchers are working on them or developing new multilevel inverter topologies as well as devising the new modulation or switching techniques for better efficiency, better power quality, less Total harmonic Distortion (THD), less number of power devices, etc. In last two decade there are different multilevel inverter topologies and modulation techniques proposed in literature. In this paper a brief survey of different multilevel inverter topologies and different modulation techniques are discussed.