This article presents the utilization of DPWM for the online condition monitoring of SiC power MOSFET switching at high switching frequencies in a three-phase inverter prototype. Due to the settling time imposed by the monitoring system, accurate measurements require low switching frequency and high modulation indexes when monitoring. To overcome these limitations, a DPWM strategy is proposed. This way, the monitored device does not switch during a certain time, and hence, the accuracy of the measurements is not compromised. The effect of the alteration of the modulation is analyzed in terms of power losses and current ripple, comparing the traditional with the proposed modulation. Moreover, online monitoring results performed in a SiC-based inverter prototype in different operating points are presented. An RDS-based thermal model is presented in order to estimate online the junction temperature.

中文翻译：

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用于SiC功率模块在线状态监测的不连续PWM

本文介绍了DPWM在三相逆变器原型中以高开关频率在线监测SiC功率MOSFET开关的情况。由于监控系统需要建立时间，因此在进行监控时，准确的测量需要较低的开关频率和较高的调制指数。为了克服这些限制，提出了一种DPWM策略。这样，被监控设备在一定时间内不会切换，因此不会影响测量的准确性。从功率损耗和电流纹波的角度分析了调制方式的变化，并将传统调制方式与建议的调制方式进行了比较。此外，还介绍了在基于SiC的逆变器原型中不同工作点执行的在线监视结果。