Leakage current is one of the key issues which need to be solved in a non-isolated photovoltaic grid-connected inverter system. In this paper, three major problems associated with the leakage current and its suppression techniques including leakage current analysis model, switching modulation mode, and new non-isolated inverter topologies are studied through literature reviews. The single-phase non-isolated photovoltaic grid-connected inverters is discussed. The advantages and disadvantages of different circuit topologies are analyzed and compared. Finally, some suggestions on improving the performance and efficiency of the non-isolated grid-connected inverter while suppressing leakage current are offered.
