Variable Gate Voltage Driving Circuits for Mitigation of Coupling Noise in Silicon Carbide MOSFET

Silicon carbide (SiC) MOSFET exhibits low channel resistance, low junction capacitances, and wider temperature range compared with silicon counterpart. However, the high dv=dt in a bridge-leg connected SiC MOSFETs induce the detrimental coupling noise, increasing device stress and EMI and restricting the converter operation at a high switching frequency. This paper presents two single-supply based variable gate voltage driving (SSVGVD) circuits for SiC MOSFETs to exploit the switching-speed capacity by mitigating the coupling noise during switching transients. Both driver circuits employ a simple auxiliary circuits comprising a transistor, zener diode, and resistor to control the gate voltage of power devices in a bridge-leg configuration. The proposed driver circuit can be easily realized with a driver IC using only positive driver supply, offering a compact, low-cost, and reliable solution. Experimental tests with SiC MOSFETs demonstrate the effectiveness of the SSVGVD gate driver.