A High-Efficiency Single-Stage DAB Microinverter with New Switching Modulation and Integrated Transformer

This paper proposes a high-efficiency modulation scheme and magnetic integration for single-stage microinverter module-level power electronics. The proposed 400W microinverter achieves full zero voltage switching for dc input voltages ranging from 18V to 58V, using a half bridge matrix-based DAB structure. The proposed switching modulation method is easy to control and enables high power density due to the use of a constant switching frequency. In addition, the integration of transformer and series inductor reduced the volume of the converter by 18%, and power loss by 50% of separated cores. To validate the proposed method, a 400W micro-inverter prototype was built and achieved a peak efficiency of 97.33% and a CEC efficiency of 96.58%.