Experimental Verification of a Gate-Drive Circuit Using Distributed Signal Processing for Fast-Switching Operation of SiC MOSFETs

This paper proposes a high-noise-immunity gate-drive circuit for fast-switching of silicon carbide (SiC) MOSFETs. The proposed gate-drive circuit is equipped with two signal processors, which are distributedly arranged on both primary and secondary sides of galvanic isolation. One of the processors calculates a duty-ratio command value, and the other generates a gate control signal via PWM processing. This enables the proposed gate-drive circuit to prevent mis-triggering of the gate control signal even when a fast-switching operation of SiC MOSFETs induces a large common-mode current in the gate-drive circuit. This paper theoretically clarifies the operating principle of the proposed gate-drive circuit with the distributed signal processing and confirms its operating performance using a double pulse testing system. Experimental results demonstrate that the proposed gate-drive circuit can drive MOSFETs without turn-off failures under a 39.2- V/ns switching condition.