Triple boost switched capacitor multilevel inverter (TB-SCMLI) with reduced components and self-voltage balance

Abstract

Multi-level inverter (MLIs) designs with switched-capacitor (SC) are on the rise due to their applicability in sustainable energy systems and high voltage applications. In this light, this paper presents a compact triple-boost switched-capacitor multilevel inverter (TB-SCMLI) topology with fewer switches and self-voltage balancing capacitors. Large spikes appear in the source current and charging currents of switched-capacitors as a result of the charging and discharging actions of the switched capacitors. In order to suppress the spikes in the source and charging currents of switched-capacitors, the proposed converter incorporates a soft switching circuit. The soft charging circuit consists of an inductor and a diode in the charging path of the proposed converter to ensure soft charging of the switched-capacitors. By inserting a small value of inductance in the soft charging circuit, the proposed converter can significantly suppress source current spikes. The proposed TB-SCMLI is able to provide seven levels of output voltage by balancing the voltage of two capacitors with the given control logic. The various SCMLIs are evaluated to determine the contribution of the suggested TB-SCMLI topology's merits and downsides. To validate the performance of the proposed TB-SCMLI, comprehensive experimental findings under various laboratory test settings have been given.