Design and Performance Evaluation of Overcurrent Protection Schemes for Silicon Carbide (SiC) Power MOSFETs

作者：Wang Zhiqiang^*; Shi Xiaojie; Xue Yang; Tolbert Leon M; Wang Fei; Blalock Benjamin J

来源：IEEE Transactions on Industrial Electronics, 2014, 61(10): 5570-5581.

DOI：10.1109/TIE.2013.2297304

• Desaturation
• overcurrent protection
• silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs)
• solid-state circuit breaker (SSCB)

Overcurrent protection of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) remains a challenge due to lack of practical knowledge. This paper presents three overcurrent protection methods to improve the reliability and overall cost of SiC MOSFET-based converters. First, a solid-state circuit breaker (SSCB) composed primarily by a Si IGBT and a commercial gate driver IC is connected in series with the dc bus to detect and clear overcurrent faults. Second, the desaturation technique using a sensing diode to detect the drain-source voltage under overcurrent faults is implemented as well. Third, a novel active overcurrent protection scheme through dynamic evaluation of fault current level is proposed. The design considerations and potential issues of the protection methods are described and analyzed in detail. A phase-leg configuration-based step-down converter is built to evaluate the performance of the protection schemes under various conditions, considering variation of fault type, decoupling capacitance, protection circuit parameters, etc. Finally, a comparison is made in terms of fault response time, temperature-dependent characteristics, and applications to help designers select a proper protection method.

• 出版日期2014-10