Modelling of Common Mode noise of one leg of SiC MOSFET based three-phase Inverter

This paper proposes a common-mode model for one leg of the SiC MOSFET based three-phase inverter. Parasitic elements of the inverter have been taken into consideration. Step by step modelling of one leg during $\frac{di}{dt}$ as well as $\frac{dv}{dt}$ of the device has been established to predict common-mode oscillation frequencies. Mathematical expressions have been established for each state of modelling. Simulation results of MATLAB and LTspice are included in this paper. 300V,10kW three-phase SiC MOSFET based inverter has been developed and a single leg of the inverter was made operational to get all the results. Hardware results from oscilloscope are provided to support proposed modelling in the time domain. Spectrum analyser results are also presented in this paper to support the results in the frequency domain.