Suppressing Inter-module Oscillations for Paralleled 10 kV SiC MOSFET Modules

This paper demonstrates the parallel connection of two 10 kV SiC MOSFET modules with a focus on eliminating inter-module oscillations during the turn-on switching event. A dual-gate driver structure is proposed to drive paralleled 10 kV SiC MOSFETs. Based on the platform, the mechanism of inter-module oscillation is observed and analyzed, revealing the cause as the circulating current flowing in the loop with the lowest impedance between paralleled modules. To dampen inter-module oscillations, ferrite beads are added to the gate loop. The effectiveness of the ferrite beads in the paralleling of medium voltage modules case is analyzed and experimentally verified by a double pulse test (DPT) with two paralleled 10 kV SiC MOSFET power modules at 6000 V/ 50 A.