基于级联常通型SiC JFET的快速中压直流固态断路器设计及实验验证  

Design and experimental verification of an ultrafast medium-voltage DC solid-state circuit breaker using cascaded normally-on SiC JFETs

作　　者：何东 徐星冬 兰征 王伟[2] HE Dong;XU Xingdong;LAN Zheng;WANG Wei(College of Electrical and Information Engineering,Hunan University of Technology,Zhuzhou 412007,China;College of Electrical and Information Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南工业大学电气与信息工程学院,湖南株洲412007 [2]湖南大学电气与信息工程学院,湖南长沙410082

出　　处：《电力系统保护与控制》2024年第5期158-167,共10页Power System Protection and Control

基　　金：湖南省自然科学基金项目资助(2021JJ40172)。

摘　　要：固态断路器(solid state circuit breaker, SSCB)是直流配电网中实现快速、无弧隔离直流故障的关键保护装置。首先提出了一种基于级联常通型碳化硅(silicon carbide, SiC)结型场效应晶体管(junction field effect transistor, JFET)的新型中压直流SSCB拓扑,直流故障发生时利用金属氧化物压敏电阻(metal oxide varistor, MOV)向SSCB主开关级联常通型SiC JFET器件的栅源极提供驱动电压,可快速实现直流故障保护。其次详细分析了SSCB关断和开通过程的运行特性,并提出了SSCB驱动电路关键参数设计方法。最后研制了基于3个级联常通型Si C JFET器件的1.5 kV/63 A中压SSCB样机,通过短路故障、故障恢复实验验证了设计方法的有效性。结果表明该SSCB关断250 A短路电流的响应时间约为20μs,故障恢复导通响应时间约为12μs,为中压直流SSCB的拓扑优化设计和级联常通型Si C JFET器件的动静态电压均衡性能提升提供了支撑。The solid-state circuit breaker(SSCB)is a crucial component in the protection of DC distribution networks in that they facilitate reliable,arc-free,and fast isolation of DC faults.First,a novel medium-voltage DC SSCB topology based on cascaded silicon carbide(SiC)junction field effect transistors(JFETs)is proposed.When a DC fault occurs,metal oxide varistors(MOVs)are used to provide driving voltage to the gate-source terminals of cascaded normally-on SiC JFETs of the SSCB main switch.These can achieve fast DC fault protection.Additionally,the operational characteristics of the SSCB turn-off and turn-on processes are analyzed in detail,and the design method of key parameters of the SSCB drive circuit is proposed.Finally,a 1.5 kV/63 A medium-voltage SSCB prototype based on three cascaded normally-on SiC JFETs is developed,and the effectiveness of the design scheme is verified through short-circuit fault and fault recovery experiments.The results indicate that the response time for the SSCB to turn off the 250A short-circuit current is about 20ms.Fault recovery conduction response time is about 12ms.This provides a foundation for the topology optimization design of medium-voltage DC SSCB and the improvement of dynamic and static voltage balance performance of cascaded normally-on SiC JFETs.

关 键 词：直流配电网 固态断路器 碳化硅结型场效应晶体管 金属氧化物压敏电阻 短路故障 

分 类 号：TM561[电气工程—电器]