A Seven-Level Inverter With Natural Balance and Boosting Capability

This paper introduces a new active-neutral-point clamped (ANPC) seven-level inverter with a switched-capacitor technique. The introduced inverter generates a seven-level ac output voltage with a maximum voltage-boosting gain of 1.5. The higher output voltage does not imply high voltage across the switches, as the maximum blocking voltage of the switches does not exceed the input voltage. The dc-link capacitor voltages are naturally balanced, and the flying capacitor achieves self-balancing through the series-parallel connection of the input voltage source, without the need for auxiliary control methods. Additionally, compared to major traditional seven-level inverters such as NPC, FC, and hybrid topologies, the proposed topology reduces the dc voltage requirement by 33.3%, eliminating the need for an intermediate dc-boosting stage and making the introduced inverter a good candidate for applications such as photovoltaic panels and full-cells systems, both characterized by a low input voltage. The operation and performance of the proposed topology are validated through simulation and experimental results.