Junction temperature balance control for paralleled SiC MOSFETs based on active gate control

Abstract

Power devices operating in parallel often experience thermal stress imbalances, which can lead to failures, especially in silicon carbide (SiC) MOSFETs. To enhance their reliability, controlling the junction temperature becomes crucial. Existing research focuses on addressing current imbalances in parallel devices, neglecting the issue of junction temperature imbalances. It is worth noting that even with balanced currents, the junction temperatures may still vary. To address this challenge, we propose a novel active gate control-based method for achieving junction temperature balance in parallel devices. This method not only ensures junction temperature balance but also effectively suppresses dynamic current peaks. To validate the effectiveness of our approach, we conducted experimental tests on a BUCK converter utilizing two parallel SiC MOSFETs. The experimental results demonstrate the achievement of junction temperature balance and excellent suppression of dynamic current peaks through the proposed method.