Single-phase transformerless nine-level inverter with voltage boosting ability for PV fed AC microgrid applications

Sci Rep. 2022 Aug 4;12(1):13442. doi: 10.1038/s41598-022-16057-x.

Abstract

This letter presents a new single-stage common ground type nine-level (9L) switched-capacitor inverter topology with single-phase operation. The primary objective of this topology is to reduce the leakage current, voltage boosting, and maintain the voltage across the switched capacitors. The output voltage (vo) can be boosted up to two times the input voltage (vin). The various modes of operations are explained in detail, and the simulation results are provided to illustrate the effectiveness of the proposed topology. Next, the experimental results are obtained from a 500 W prototype setup and tested under different scenarios such as load variations, input voltage, and modulation index. Both simulation and experimental results have a good agreement regarding efficiency and performance. Finally, a detailed comparative study is performed with other recent 9L switched-capacitor inverters to prove the merits of the proposed topology.