Research on Voltage Oscillation Suppression of SiC MOSFETs Based on Gate‐Notch Filter and PCB Optimization

ABSTRACT Wide‐bandgap devices, exemplified by SiC MOSFETs, significantly enhance the performance of power converters due to their high switching speed. However, such rapid switching introduces oscillations within the circuit, leading to additional voltage stress on the power devices, increased electromagnetic interference (EMI), and potential threats to system stability. To suppress these switching oscillations, this paper first establishes a model of a SiC MOSFET‐based half‐bridge circuit that includes parasitic parameters, and subsequently analyzes the switching transient states in a segmented manner. On this basis, a gate‐notch filter is designed, and an initial estimation of its parameters is derived through a dynamic characterization approach based on the transfer function. Furthermore, an oscillation‐characteristic index function is constructed, and the filter parameters are finely optimized using the Pareto front method. Additionally, the influence of power loop parasitic parameters on oscillation is evaluated by analyzing circuit states during switching transients. To mitigate these parasitics, an optimized PCB layout for the power loop is proposed, which achieves partial cancellation of leakage inductance through layered stacking. The effectiveness of the proposed oscillation suppression method is validated through both simulation and experimental results, demonstrating improved system stability.