A MHz-Pulse-Transformer Isolated Gate Driver With Signal-Power Integrated Transmission for Medium-Voltage SiC MOSFETs

The conventional isolated gate driver (GD) solution for the medium-voltage (MV) SiC
mosfet
separates the signal and power transmissions and requires a bulky GD power supply (GDPS). This article presents a signal-power integrated GD for MV SiC
mosfet
s with a compact footprint. The proposed GD transmits both the pulsewidth modulation (PWM) signal and GD power by 20-MHz modulated class-E resonant flyback converters, where the transmitted GD power can maintain constant within the full PWM duty-cycle range (i.e., 0%–100%). In addition, the PWM signal transmission of the proposed GD achieves a low total propagation delay time < 75 ns by utilizing the fast transient of 20-MHz RFCs and the edge-based envelope detector. A printed-circuit-board-based coreless transformer is integrated into the proposed GD to achieve an insulation voltage higher than 10 kV
_RMS
and a low coupling capacitance of 5.85 pF. The common-mode transient immunity of proposed GD is higher than 100 V/ns, which is beneficial to drive MV SiC
mosfet
s with high
dv/dt
. The proposed GD does not require additional GDPSs nor fiber-optics, which achieves a smaller size compared to conventional isolated GDs and is promising to be integrated into SiC
mosfet
module packages. Experimental results on 3.3 kV and 10 kV SiC
mosfet
s are provided to validate the effectiveness of the proposed GD.