Design of a High Efficiency and High Power-Density GaN-Based Microinverter

Gallium-Nitride (GaN)-based microinverters play a crucial role in the next generation of highly integrated distributed photovoltaic (PV) systems. The objective of this paper is to propose an effective and practical design process for a 400W natural-cooled GaN-based microinverter with both high efficiency and high power-density. Independent optimizing parameters are proposed, and loss models of key components are established for efficiency optimization. To restrict the selection of optimized parameters, constraints are proposed. Loss calculations are performed, and the results are used to determine the optimal parameters. Accordingly, a prototype is built and experimentally verified, exhibiting a boxed power density of 106 W/in
³
and a full load efficiency of 97.08%.