Current Balancing of Paralleled SiC MOSFETs for a Resonant Pulsed Power Converter

Paralleling silicon carbide (SiC) MOSFETS is a cost-effective solution for increasing pulse current rating. However, the device SiC MOSFETS mismatch and asymmetrical circuit layout would lead to imbalance current of the paralleled SiC MOSFETS. In this letter, we propose a passive approach, that is, a coupled inductor instead of the conventional resonant inductor, which is used for a resonant pulsed power converter. The coupled inductor enables even current sharing of the parallel SiC MOSFETs, and also helps with pulsewidth adjustment, which leads to a simplified system without complex control circuit compared with the active solution. The configuration of the proposed topology, operating principle, imbalance current limitation mechanism, and design guidelines are fully discussed and presented. Additionally, experiments are carried out to verify the analysis and effectiveness of the proposed solution. The proposed method can be extended to the scenario with more than two parallel.