Thermal Design and Parametric Optimization of A Naturally Cooled GaN Based Microinverter Packaging Using CFD Simulations

Microinverters are gaining popularity over traditional string inverters. They provide higher efficiency during partial shading. The size of microinverters is shrinking while Gallium Nitride (GaN) based switches further increases the efficiency. However, the smaller sizes cause a greater challenge in thermal management of the various components in the inverter. This paper presents a study utilizing design of experiments to optimize the geometry of the microinverter packaging to maximize heat dissipation with the available design space of a 1. 6kW4-channel GaN based Microinverter. The optimization methodology including constraints, variables and approach used to manage the thermal concerns are introduced and the results from the simulations discussed in this paper. Minimizing the sum of temperatures of the various components is considered the objective of the optimization problem. The simulation results were than used to develop a prototype for experimental testing and verification.