The SiC devices have been a strong competitor than the conventional Si devices due to the superior characteristics of high operating voltage, low forward voltage, fast switching speed, and high operating temperature. However, the maturity of SiC technology is still in the progress of catching up with the Si devices, the device cost for SiC MOSFET is still much higher than the Si devices. In addition, the maximum current rating of the available SiC devices are still lower than the Si devices, this also limits the utilization of SiC device in high-power applications. In order to combine the Si IGBT’s advantages of low cost and high overload capability and the SiC MOSFET’s advantages of low switching loss. The Si IGBT and SiC MOSFET are connected in parallel as a new switching unit. In this dissertation, the Si IGBT and SiC MOSFET hybrid switch (Si/SiC HyS) in the application of voltage source converters is investigated.