In the case of high switching frequency,the bridge arm crosstalk caused by the parasitic parameters of SiC MOSFET in the traditional drive are more serious. However,most of the existing crosstalk suppression drive circuits suppress the crosstalk at the expense of increasing the switching loss,prolonging the switching delay and adding the control complexity. Therefore,based on the idea of reducing the impedance of the drive loop in the process of crosstalk generation,a novel active Miller clamp gate drive design is proposed by adding PNP triodes connected in series with diodes and capacitors between the gate and source,and its working principle is analyzed. The parallel capacitance parameters of the improved drive circuit are also calculated and designed. Finally,an experimental platform of double-pulse test for a synchronous Buck converter with DC bus voltage of 300 V was built,and the novel crosstalk suppression drive circuit was compared with the traditional and typical crosstalk suppression circuits in terms of the positive and negative crosstalk voltage spike suppression effects and the turn-on and turn-off speeds. Experimental results show that compared with those of the traditional and typical crosstalk suppression circuits,the positive and negative voltage spikes of the proposed crosstalk suppression drive circuit were reduced by 80％ and 40％,respectively,and the switching delay of the device was reduced by 32％ in the meantime.
维普
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