Optimum Design of Wireless Power Transfer-Based Snubbers for SiC MOSFET Switching Oscillations

This letter proposes a novel wireless power transfer (WPT)-based snubber circuit aimed to suppress the ringing of SiC mosfet resulting from parasitic impedances in the switching circuit. The key innovation lies in the artful transfer of the ringing energy to an optimally designed receiver via magnetic resonant coupling. It reveals that the oscillation time of switching ringing can be reduced by up to 67%, significantly expanding the upper limit of the switching frequency and reducing electromagnetic interference. Compared to the traditional RC snubber, permissible voltage and energy loss of the WPT snubber is reduced by 87.84% and 86.84%. This technology greatly reduces the sizes of passive components, resulting in a huge enhancement of power density. Finally, both theoretical analyses and experimental results confirm the effectiveness of the proposed system.