Common-Ground Single-Stage Transformerless Inverter using Switched-Capacitor for Single Phase PV Application

Abstract

This paper presents a new topology of transformer-less inverters (TLI) for photovoltaic (PV) applications. It is based on the common ground configuration (CGC). CGC TLI has an inherent ability to reduce the leakage current (LC), one of the principal issues. This uses eight switches, two switched capacitors (SC) and a dc linked capacitor to generate the 5-level double-boosted output voltage. This inverter is suitable for grid integration of PV voltage that is lower than the grid voltage because of the boosting capability. The SCs are self-balanced by charging and discharging at a fundamental frequency. The Inverter control is accomplished by level shift pulse width modulation (LS-PWM). Further, component selection procedures and comparative studies are carried out. The performance of the topology is further verified on MATLAB/Simulink.