In order to adapt to the development trend of high frequency and high power density of converter products, the application of high-power all-SiC-MOSFET device in converter was studied. The problem of stray parameters and bridge arms crosstalk in application of all-SiC-MOSFET devices was discussed. The effect of drive resistance and absorber on the closing peak of high-power all-SiC-MOSFET device was studied. The application of high-power SiC-MOSFET device in Boost converter was studied. The experiment showed that compared with the original Si-IGBT, the adoption of SiC-MOSFET device could bring an all-round improvement in light weight, working frequency and efficiency to the converter.