With the rapid development of semiconductor technology, the applications of silicon carbide (SiC) MOSFETs have been booming in recent years, where short-circuit fault protection plays an important role. In this paper, voltage and current waveforms under different short-circuit faults are analyzed. Then, two types of turn-off modes, namely a soft turn-off mode and a two-stage turn-off mode are introduced. The peak voltage, short-circuit energy and anti-interference performances of SiC MOSFETs under the different turn-off modes are analyzed and compared at various DC bus voltages. The obtained experimental results show that the soft turn-off mode can reduce voltage spikes. However, it needs a blanking time to improve the anti-interference performance of the system, which increases the short-circuit energy. For the two-stage turn-off mode, the anti-interference performance of the system is improved and the short-circuit energy is obviously decreased. However, the peak voltage generated by the two-stage turn-off mode is slightly larger than that of the soft turn-off mode. On the whole, the two-stage turn-off mode is more competitive than the soft turn-off mode for the short-circuit fault protection of SiC MOSFETs.

中文翻译：

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用于短路故障保护的碳化硅 MOSFET 的关断模式

随着半导体技术的飞速发展，碳化硅（SiC）MOSFET的应用近年来蓬勃发展，其中短路故障保护发挥着重要作用。本文分析了不同短路故障下的电压和电流波形。然后，介绍了两种关断模式，即软关断模式和两级关断模式。分析比较了不同直流母线电压下SiC MOSFET在不同关断模式下的峰值电压、短路能量和抗干扰性能。得到的实验结果表明，软关断模式可以减少电压尖峰。但是，需要消隐时间来提高系统的抗干扰性能，增加了短路能量。对于两级关断模式，提高了系统的抗干扰性能，明显降低了短路能量。但是，两级关断模式产生的峰值电压略大于软关断模式。综合来看，对于SiC MOSFET的短路故障保护，两级关断模式比软关断模式更具竞争力。