The Active Gate Drive Based on Negative Feedback Mechanism for Fast Switching and Crosstalk Suppression of SiC Devices

This article introduces the negative feedback into the gate drive. It proposes a negative feedback active gate drive (NFAGD) for silicon carbide devices to fully utilize their potential of high switching-speed capability in a phase-leg configuration. An auxiliary P-channel mosfet is introduced to construct a negative feedback control mechanism. Due to the negative feedback mechanism, the proposed drive can automatically attenuate the disturbance from the complementary device of the phase-leg. Compared to conventional gate drives, the proposed drive can suppress the crosstalk without influencing the switching speed, thus enables coordinated optimization of gate voltage stability and switching behavior. This article analyzes the operation principle and then recommend the fundamental design principle for the proposed NFAGD. Finally, experiment results demonstrate the effectiveness of the proposed NFAGD.