碳化硅基直流固态断路器短路保护方法  

Short Circuit Protection Method of SiC Based DC Solid State Circuit Breaker

作　　者：秦海鸿[1] 莫玉斌 张英[1] 杨跃茹 赵朝会[2] QIN Haihong;MO Yubin;ZHANG Ying;YANG Yueru;ZHAO Chaohui(College of Automation Engineering,Nanjing University of Aeronautics&Astronautics,Nanjing,211106,China;College of Electrical Engineering,Shanghai Dianji University,Shanghai,201306,China)

机构地区：[1]南京航空航天大学自动化学院,南京211106 [2]上海电机学院电气学院,上海201306

出　　处：《南京航空航天大学学报》2020年第2期207-214,共8页Journal of Nanjing University of Aeronautics & Astronautics

基　　金：国家自然科学基金(51677089)资助项目;中央高校基本科研业务费专项资金(NS2015039,NS20160047)资助项目;南京航空航天大学研究生创新基地(实验室)开放基金(kfjj20170308)资助项目。

摘　　要：碳化硅器件比硅器件具有更低的导通电阻,用其制作直流固态断路器可以大大降低其通态损耗,减轻散热压力。然而相比于硅器件,由于碳化硅器件管芯面积小,电流密度大,其短路能力相对较弱,短路保护要求更高。为确保碳化硅器件安全可靠工作,提高碳化硅基直流固态断路器的可靠性,对比分析了硅基与碳化硅基MOSFET的短路能力,揭示了其器件恶化机理,研究了栅源极电压箝位方法,并结合去饱和检测,提出了一种基于源极寄生电感的"软关断"短路保护方法,制作了直流固态断路器样机进行实验验证。实验结果表明,所提方法可以降低功率器件的关断电压应力、抑制短路电流,适合碳化硅基直流固态断路器短路保护。Compared with silicon devices,silicon carbide devices have low on-state resistance,which can reduce on-state loss of DC solid state circuit breaker and reduce the pressure of cooling. However,silicon carbide MOSFET has the smaller die area and the higher current density than silicon MOSFET,which leads to the weaker short-circuit ability, the shorter short-circuit withstand time and the higher protection requirement. In order to ensure the safe and reliable operation of silicon carbide power devices and improve the reliability of silicon carbide based DC solid state circuit breakers,the short circuit capability of silicon and silicon carbide MOSFET are analyzed and compared. The internal fault mechanism is revealed. In addition,gate-source voltage clamp methods are elaborated and compared. Combined with desaturation detection,a"soft turn-off"short-circuit protection method based on source parasitic inductance is proposed. Finally,a DC solid state circuit breaker prototype is built for experimental verification. Experimental results show that the proposed method can not only reduce the voltage stress of the power device,but also suppress the short circuit current,suggesting that it is an effective short-circuit protection method for DC solid state circuit breaker based on silicon carbide devices.

关 键 词：碳化硅 直流固态断路器 短路能力 短路保护 

分 类 号：TM386[电气工程—电机]