An improved seven-level switched-capacitor-based neutral-point clamped inverter

Multilevel inverters (MLIs) have seen significant growth in a variety of medium- to high-power industrial applications and become mature viable solution for renewable energy systems over the past decade. The major concerns MLIs are high component count buck-type feature ac output voltage when used grid-connected renewable-energy-based sources such as solar photovoltaic (PV) panels. As another option, switched-capacitor (SC)-based inverter possessing boost ability is prime meet requirements power applications. Integrating an SC network with neutral-point clamped (NPC) structure makes leakage current alleviation transformerless PV systems. In this article, improved SCMLI based on NPC proposed reduce number active switches charging loop, significantly reducing loss. It can generate seven levels boosting self-balancing capacitors within single-stage conversion. working principle topology, circuit description, control technique presented. Further, was compared other recent topologies show its superiority. end, laboratory prototype developed tested seven-level module under steady-state dynamic conditions validate practical viability configuration. inverter’s maximum efficiency 97.5% at 1.2 kW rated power.