Two Flying Capacitors Cascaded Sub-Multilevel Inverter with Five Switches for DC–AC Conversion

Abstract

This paper presents a novel topology for cascaded multilevel inverters that only two flying capacitors apply single DC source voltage to all sub-multilevel inverters. The output voltages of each sub-multilevel inverters unit, which each unit can produce five voltage levels, are cascaded using low frequency transformers. Suggested topology have advantages of both original flying capacitor and cascaded H-bridge and in the same time reduces the amount of switching devices, DC sources, capacitors and natural self-balancing of the flying capacitors. Besides, it can operates in symmetric an asymmetric states and four algorithms for calculating of turn ratio of transformers have been presented. Simulation results of the proposed inverter are presented and carried out by MATLAB/SIMULINK to verify its voltage generating ability.

Keywords

• Symmetric state, Asymmetric state, Flying capacitor, Cascaded transformer

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