Operation analysis and comparison of Multilevel Si IGBT and 2-level SiC MOSFET inverter-based high-speed drives with long power cable

Silicon Carbide (SiC) MOSFETs, as wide-bandgap semiconductor device, are becoming increasingly popular. They can switchat much higher frequency when compared to their silicon (Si) counterpartsand canviably supply high-speed electrical drives. High-speed machines are profitably used in aeronautical or electric vehicle applications, offering drastic reduction of encumbrance and weight.On the other hand, industrial motor drivesusually include a long-shieldedcableto connect the inverter to the induction motor. This, together with high frequency operation of the SiC devices, emphasizes the effect of parasitics such as stray inductances and capacitances, whichgenerates reflected wave transient overvoltage on motor terminals. In this paper, switching performance ofSiC MOSFETs is systematically studied and compared to the performance of Si devices for low-voltage induction motor loads. For the Si-based inverter configuration the Neutral Point Clamped (NPC) 3-level inverter has been chosen, being it highly utilized in industrial applications. The two systems arecompared in terms of switching performance, overvoltages, and power lossesfor the same output voltage capabilities. Simulationsarecarried out by realisticmodels of power switch modules. The goal was to analyzepotential solutions for switching performance improvement and mitigation of reflected waves, as well as for future analysis of the electric aging phenomena.