SiC MOSFET短路特性及过流保护研究  

Research on Short-circuit Characteristics and Overcurrent Protection of SiC MOSFET

作　　者：王占扩 童朝南[1] 黄伟超[2] WANG Zhankuo;TONG Chaonan;HUANG Weichao(School of Automation and Electrical Engineering,University of Science and Technology Beijing,Haidian District,Beijing 100083,China;Collaborative Innovation Center of Key Power Energy-Saving Technology in Beijing(North China University of Technology),Shijingshan District,Beijing 100144,China)

机构地区：[1]北京科技大学自动化学院,北京市海淀区100083 [2]北京市电力节能关键技术协同创新中心(北方工业大学),北京市石景山区100144

出　　处：《中国电机工程学报》2020年第18期5751-5759,共9页Proceedings of the CSEE

摘　　要：为了提高电力电子装置中SiC MOSFET可靠性,对SiC MOSFET短路特性和过流保护进行研究。首先在不同的母线电压和环境温度下,对处于短路状态的SiC MOSFET的电流IDS和导通压降VDS(ON)进行测量和分析,在此基础上设计基于VDS(ON)检测的过流保护电路,比较两种消隐电路对保护的影响,实验证明,在消隐电路工作时,较大的充电电流可有效缩短保护时间,但电路功率消耗较大。针对半桥直通短路,根据SiC MOSFET的工作特性,提出一种基于门极电压VGS检测的直通短路保护方法,将半桥两只SiC MOSFET的VGS电压于门极阈值电压比较,如果同时超过阈值电压,可判断发生直通短路,实验表明,提出的保护方法具有保护时间快,短路电流小的特点,与VDS(ON)检测的过流保护电路配合,可以有效地保护SiC MOSFET。The short circuit characteristics and overcurrent protection of silicon carbide(SiC) metal-oxide-semiconductor field-effect transistor(MOSFET) was studied. Firstly, the short-circuit current and voltage drop VDS(ON) of SiC MOSFET in short circuit state were measured and analyzed under different bus voltage and ambient temperature. Based on the analysis of short circuit characteristics, an overcurrent protection circuit based on VDS(ON) detection was designed, and the effects of two kinds of blanking circuits on protection were compared. the experimental results show that when the blanking circuit works, the larger charging current can effectively shorten the protection time. But the power consumption of the circuit is high. A short-through short-circuit protection method based on gate voltage VGS voltage detection was proposed. The gate voltage of two SiC MOSFET in half-bridge was compared with the gate threshold voltage. If the gate voltage of both SiC MOSFET exceeds the threshold voltage, it can be judged that a shoot-through short circuit has occurred. The experimental results show that the proposed shoot-through protection method has the characteristics of fast protection time and low current, and can protect SiC MOSFET effectively.

关 键 词：SiC MOSFET 特性短路 过流保护 VDS(ON)检测 VGS检测 

分 类 号：TM464[电气工程—电器]