Despite the projected growth in light electric-vehicles (EVs), the innovation in drive-train is limited due to cost-constraints. In this paper, wide-bandgap (WBG) SiC/GaN based drive-train inverter designs for next-generation light EVs are evaluated in comparison with conventional Si-based inverter solutions. The analysis is executed by considering the six-switch inverter topology, space-vector-modulation (SVM), accurate power loss and volume models and cost estimates. Detailed simulations are carried out for 10 kVA inverter designs at 72 V and 300 V DC-link voltages utilizing the manufacturer’s thermal models for WBG and Si-based devices. A comparative evaluation reveals that WBG-based drive-inverter designs for light EVs can provide considerable improvements in efficiency and power-density with a slight increase in cost compared to Si-based designs. A SiC-based 10 kVA drive-train inverter prototype is fabricated which operates at 300 V DC-link voltage. It demonstrates an efficiency of 98.75%, power-density of >40 kVA/L and has a cost price of USD 485, which are quite close to the respective simulation/theoretical model based estimates.
