Time-Domain and Frequency-Domain Analysis of SiC MOSFET Switching Transients Considering Transmission of Control, Drive, and Power Pulses

Three types of pulses, namely the control, drive, and power pulses, coexist in power electronics systems. The transmission of them embodies the idea to control energy flow with signal flow. However, due to the nonideal performance of the semiconductor switches and the parasitic elements, significant delay and distortion are inevitable during the transmission, causing severe challenges in terms of both device- and system-level performance. Taking silicon carbide (SiC) MOSFET-based system as an example, this article studies the transmission of the three pulses. Time-domain studies are provided first to derive the characteristic parameters of the delay and distortion. Based on the time-domain expressions, a pulse decomposition method is proposed to study the frequency spectrum of the power pulse considering all major transient factors. Experimental results are provided to verify the proposed method and the acquired results. Based on the analyses, the impact of pulse delay and distortion on system performance is summarized, and the general idea of active gate controlling for the power pulse is briefly discussed. This article provides quantitative studies and relevant discussions from the perspective of pulse transmission to improve the analysis, gate-drive design, and active gate control of switching transient.