Evaluation of Inverter Architectures for Output Voltage Overshoot Reduction in WBG Electric Drives

The electrification of Non Road Mobile Machinery (NRMM) has brought to light several challenges for electrical actuation systems currently in use, above all their low power density. To hit the required targets, a strong increase of the performance, for both machines and drives, will be required. On the power electronic side, wide bandgap devices promise to enable much higher operating frequencies and temperatures, that can drastically cut down on the size of heatsinks and all magnetic components. However, their fast transition times produce an increased electric stress on the stator insulation system, which can experience partial discharges in some cases, thus quickly degrading. This paper strives to thoroughly compare several drive architectures that can mitigate this challenge, guiding the topology choice by analyzing power efficiency, ability to limit or eliminate overvoltages, reliability of the inverter structure and costs.