A Variable DC-Link Voltage Determination Method for Motor Drives with SiC MOSFETs

This paper proposed a variable DC-link voltage determination method for motor drive using Silicon Carbide (SiC) MOSFETs. Usually, the voltage source inverter (VSI) with a constant DC-link voltage is adopted for the motor drive applications. However, operating in low-speed region does not require high voltage and higher voltage causes higher voltage harmonics. On the other hand, lower DC-link voltage limits its acceleration response. Therefore, an approach to determine the appropriate variable DC-link voltage is proposed in this paper. The power switches in the hardware prototype are implemented with SiC MOSFETs to achieve higher performance. Both simulation and experimental results are shown to verify the performance of the proposed DC-link voltage determination method.