An Active Gate Driver of Voltage Overshoot Suppressing for SiC MOSFETs

Compared to silicon-based devices, silicon carbide metal-oxide-semiconductor field-effect transistors (SiC MOSFETs) offer faster switching speeds. However, the fast switching speed of SiC MOSFETs and the inevitable parasitic inductance in the power loop will cause the severe voltage overshoot during the device turn-OFF transient. This paper proposes an active gate driver (AGD) that injects additional gate current into the device during specific stage of the turn-OFF process. This method effectively suppresses v<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ds</inf> overshoot peak under variable load current conditions while exerting less effect on switching speed and switching loss. Finally, an experimental platform is designed to validate the proposed AGD scheme. The experimental results demonstrate that the method achieves a better trade-off between voltage overshoot and turn-OFF loss, while effectively suppressing the v<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ds</inf> overshoot peak under variable load current conditions.