New single-stage soft-switching photovoltaic grid-connected flyback micro-inverter

Due to the leakage inductance of transformer, flyback inverter needs snubber in order to limit voltage spike across the primary switch. However in conventional flyback inverter, energy of leakage inductor is dissipated. In this paper, a new soft switching flyback inverter is proposed. The auxiliary circuit of the proposed inverter is composed of one auxiliary switch. The auxiliary circuit provides soft switching condition for main switch. All main and auxiliary switches are soft switched. In this paper, operating principles, theoretical analysis and design procedure are presented. Also, simulation results are presented to verify the validity of theoretical analysis.