Efficiency characterization and thermal study of GaN based 1 kW inverter

Rapid advancement of gallium nitride (GaN) based device technologies enables the possibility to design inverters that have superior performance capabilities compared to Si-based inverters. It is prevalently acknowledged that GaN-based switching devices outperform the Si-based counterparts in many aspects such as lower power consumption, and faster switching frequencies. GaN devices will benefit many applications such as hybrid and plug-in electric vehicles, solar power inverters, industrial motor drives, and aerospace. Nevertheless, the superiorities of GaN devices in inverter design have not been fully explored by researchers, and the purpose of this paper is to evaluate the high-efficiency capabilities of inverters that can be achieved using these new devices and the resulting benefits on the thermal aspect. As a case study, 1 kW GaN FETs inverter is considered. Loss and efficiency analysis is performed under various load conditions, and the requirements on heat sink for various ambient temperatures are specified according to the loss values obtained. Analysis results are compared with conventional Si-based inverters.