Design and Optimization of a Single-Stage Photovoltaic Microinverter with Integrated Magnetics

Abstract:
High-frequency link resonant inverter has the potential to achieve higher efficiencies due to its single-stage power conversion structure. An optimized design is carried out for a single-stage high-frequency link resonant inverter in this paper. First, the optimal phase shift angle between the primary and secondary sides is applied to reduce the RMS current of the resonant tank to reduce the conduction loss. And there is always a set of switches on the secondary that operate at low frequency, which can reduce switching losses. Then the transformer and resonant inductor in the converter are integrated, and the design is optimized based on loss and area. The final prototype is built to achieve a power density of 46 W/in3 and a full load efficiency of 95.3%.