J. Nishi , M. Roshini, G. K. Gowri , K. Immanuvel Arokia James
This paper analyses a new transformer less, single-phase PV inverter topology generates no common-mode voltage, exhibits a high efficiency. Grid-connected PV systems include a line transformer in the power-conversion stage, for galvanic isolation between the grid and the PV system, thus providing personal protection. Furthermore, it strongly reduces the leakage currents. But the efficiency is largely decreased due to the power losses and the line transformer is large, heavy and expensive. In this paper, a new topology, based on the H-bridge with a new ac bypass circuit consisting of a diode rectifier and a switch with clamping to the dc midpoint, is proposed. The topology is simulated and experimentally validated, and a comparison with other existing topologies is performed. High conversion efficiency and low leakage current are demonstrated.