Adaptive Multi-Level Active Gate Drivers for SiC Power Devices

State-of-the-art silicon carbide (SiC) power devices provide superior performance over silicon devices with much higher switching frequencies/speed and lower losses. High switching speed is preferred for achieving low switching loss, yet high dv/dt and di/dt can result in high EMI emission during switching transients. These switching dynamics can be controlled by the device gate driving strategy. The multi-level active gate driver (AGD) approach is able to tradeoff the switching losses with the dv/dt and di/dt for each switching transient. A novel three-level (3-L) AGD for SiC power mosfet trajectory control is introduced. Its turn-off profile has a shorter turn-off delay compared to any existing methodology. Accordingly, a comprehensive datasheet-driven trajectory model for the online model-based optimization of the 3-L turn-off is introduced. The main factors that impact the 3-L turn-off performance are analyzed with this model. The experimental results of double pulse tests validate the approach. Additionally, the benefits of the proposed 3-L AGD method over two-stage turn-off and conventional gate drivers on the market are illustrated through experiments.