A Seven-Level Common Ground Inverter for Power Quality Improvement in a Distribution Network

Power quality (PQ) improvement in distribution networks with integrated solar photovoltaic (PV) systems is a growing challenge, especially with the widespread adoption of transformer-less inverters. These inverters are extensively utilized for their high-power density, cost-effectiveness, low dv/dt stress, and enhanced efficiency. However, they often suffer from ground leakage currents, compromising safety and PQ. This paper presents a modified seven-level common-ground (CG) transformer-less inverter topology that eliminates the need for an H-bridge and significantly reduces component count. The proposed inverter utilizes a single-input switched capacitor network to generate a seven-level output voltage, achieving a triple voltage gain while inherently suppressing ground leakage current through the CG configuration. The performance of the proposed topology is validated experimentally and verifies the triple voltage gain with improved PQ, making it a suitable solution for nextgeneration solar PV-based distribution systems.