Design and Comparison of SiC MOSFET inverter for Underwater High-Power and High-Speed Motor

The proposal of deep and high sea and the application target of high maneuverability and concealment means that the future power system of underwater vehicles should have higher speed, power density, and efficiency. In the application of underwater high-speed and high-power motors, traditional Si-based power devices face the limitation of switching performance, and there are insufficient chopping times in the commutation cycle of the motor, which brings large torque ripple and loss to the motor. Therefore, in this paper, the power device loss was analyzed first. A simulation model was established in PSpice to compare the loss of SiC metal-oxide-semiconductor field-effect transistor(MOSFET) and insulated gate bipolar transistor(IGBT) at different switching frequencies and temperatures, and the motor torque ripple at different switching frequencies was compared in Simulink. The SiC power device had the advantages of high switching frequency and low switching loss, and then the SiC MOSFET was applied to the high-power and high-speed motor inverter module of underwater vehicles. The software and hardware of the inverter module were designed and compared with the IGBT inverter in terms of efficiency. At the same time, the influence of SiC MOSFET on the motor torque ripple at high frequency was analyzed, which provides a useful reference for SiC MOSFET application in underwater vehicles.