48V 25kW GaN Inverter Design Consideration for Urban-Sized Electric Utility Vehicles

Abstract

This paper presents the design considerations for a 48V multiphase GaN inverter to drive a six-phase permanent magnet synchronous motor (PMSM) with 25kW/35kW of continuous/peak power. This electric drivetrain system can be foreseen as an emerging technology for urban-sized electric utility vehicles. The inverter’s critical components such as GaN switches and dc-link capacitors are pre-sized using analytical calculations whereas a liquid-cooled heatsink is designed using finite element analysis with Ansys Icepak. The prototype of a half-bridge phase module is manufactured to evaluate the gate driver board’s capability for the high parallelization of GaN switches and the PCB layout of the power board based on an insulated metal substrate. Preliminary experimental results are presented to demonstrate the feasibility of the study.