100 kW氮化镓牵引逆变器的系统性效率-密度协同优化：方法与集成

The increasing pursuit of high efficiency and power density in EV traction inverters is accelerating the deployment of the wide bandgap device, including silicon carbide (SiC) and gallium nitride (GaN). As the efficiency-density boundary of the SiC traction inverter has approached its limitation, the traction inverter utilizing GaN devices, with lower power loss and higher switching speed, is considered as a promising solution. Focusing on the GaN traction inverter for EV applications, this article proposes a design methodology considering the co-optimization of the pursued efficiency and power density objectives. Based on the created mathematical models of design concerns, including power loss, dc-link ripple, and thermal resistance, the efficiency-density design domain of the GaN inverter is established, upon which the optimal design space of the efficiency-density is determined through Pareto frontier analysis. Based on the co-optimization results, a 100 kW / 400 V GaN traction inverter prototype is compactly integrated, incorporating meticulously designed key components, including the GaN power module, dc-link capacitor, and heat sink. Experimental validation confirms the effectiveness of the proposed co-optimization methodology and demonstrates the feasibility of the integrated GaN inverter, achieving the high power density 62.1 kW/L and peak efficiency 99.3%.