A High step-Up Common Ground Thirteen-Level Switched-Capacitor Inverter with Reduced Components Count

This paper presents a common -ground switched-capacitor multilevel inverter (CGSCMLI) topology designed for photovoltaic (PV) systems. The proposed inverter achieves a DC voltage gain of six and generates thirteen output voltage levels. This topology is capable of boosting the low output voltage characteristic of PV modules directly to grid-compatible levels, thereby obviating the need for magnetic components such as transformers. Key features include inherent capacitor voltage self-balancing and low total harmonic distortion (THD), measured at 10.85%, achieved without requiring large output filters. The common-ground configuration(CGC) ensures a shared ground reference between the PV source and the load, effectively mitigating leakage currents common in transformerless PV installations. In comparison to existing CGSCMLI topologies, the proposed design utilizes fewer switching devices and capacitors, resulting in a potentially lower overall system cost relative to comparable designs. A 200-W laboratory prototype was constructed and validated through experimental testing, demonstrating an overall efficiency of 96.09% and a peak efficiency of 96.82% when supplying standalone loads.