PV microinverter solution for high voltage gain and soft switching

This paper proposes a high-gain flyback type microinverter for PV power generation. The proposed topology integrates a voltage-doubler circuit with the flyback converter to produce the high voltage-conversion gain. The solution is effective to minimize the high demand of the winding turns ratio in the flyback transformer. Besides, an active-clamp circuit is employed in the primary side for the resonant operation. The solution reduces the voltage and current stress and supports zero voltage switching (ZVS) of the power switching. The stress reduction achieved by the resonant operation further minimizes the conduction loss of the converter. A prototype is constructed and tested to show the experimental performance, which verified the advantages of the proposed solution for PV microinverter applications.