Noise suppression in SiC-MOSFET body diode turn-off operation with simple and robust gate driver

摘要

SiC-MOSFETs are being increasingly implemented inpower electronics systems as low-loss, fast switching devices. Despite theadvantages of an SiC-MOSFET, its large dv/dt or di/dt has fear of electromagneticinterference (EMI) noise. This paper proposes and demonstratesa simple and robust gate driver that can suppress ringing oscillation andsurge voltage induced by the turn-off of the SiC-MOSFET body diode.The proposed gate driver utilizes the channel leakage current methodology(CLC) to enhance the damping effect by elevating the gate-source voltage( _(GS)) and inducing the channel leakage current in the device. The gatedriver can self-adjust the timing of initiating CLC operation, which avoidsan increase in switching loss. Additionally, the output voltage of the GSelevation circuit does not need to be actively controlled in accordance withthe operating conditions. Thus, the circuit topology is simple, and ringingoscillation can be easily attenuated with fixed circuit parameters regardlessof operating conditions, minimizing the increase in switching loss. Theeffectiveness and versatility of proposed gate driver were experimentallyvalidated for a wide range of operating conditions by double and singlepulse switching tests.