A Novel Technique for the Suppression of the Displacement Current Through Power Module Base-Plate Capacitance

The voltage gradient is increased to reduce the switching losses in the wide-bandgap (WBG) semiconductors, which causes the higher power density of the system. Fast rise and fall times during switching of WBG semiconductors result in capacitive non-linearities and displacement currents through power module parasitic capacitances, which needs an appropriate filter design During the switching in the power module, the capacitive current flows through the parasitic capacitance of the power module, which causes the disturbances in the system. This leads to the need for a more oversized filter design, which then increases the overall cost and volume of the system and reduces the efficiency of the system. This paper proposes a novel technique to suppress the capacitive displacement currents without switching speed reduction. The proposed method reduces the volume of the common-mode choke (CMC) and addresses the electromagnetic interference (EMI) and electromagnetic compatibility (EMC) issues. The system was experimentally tested using the commercial 1700 V silicon carbide (SiC) half-bridge power module BSM300D12P2E001 to validate the proposed scheme.