中国电力 ›› 2021, Vol. 54 ›› Issue (12): 73-80.DOI: 10.11930/j.issn.1004-9649.202111031

• 国家“十三五”智能电网重大专项专栏:(十)高压碳化硅器件及应用技术 • 上一篇    下一篇

1 200 V SiC MOSFET参数分散性对并联均流的影响分析

吴沛飞, 汤广福, 杨霏, 杜泽晨   

  1. 1. 先进输电技术国家重点实验室(全球能源互联网研究院有限公司), 北京 102211
  • 收稿日期:2021-08-14 修回日期:2021-11-10 出版日期:2021-12-05 发布日期:2021-12-16
  • 作者简介:吴沛飞(1989-),男,博士,从事功率半导体研发、测试、碳化硅电力电子器件在高压电力系统中的应用,E-mail:wupeifei2@163.com;汤广福(1966-),男,博士,高级工程师(教授级),从事从事电力系统电力电子技术研究,E-mail:gftang@geiri.sgcc.com.cn
  • 基金资助:
    国家电网有限公司科技项目(碳化硅MOSFET沟道自对准工艺研究,5455GB190011)

Influence of the Parameter Dispersion of Domestic 1 200 V SiC MOSFET on Parallel Current Sharing

WU Peifei, TANG Guangfu, YANG Fei, DU Zechen   

  1. 1. State Key Laboratory of Advanced Power Transmission Technology (Global Energy Interconnection Research Institute Co., Ltd.), Beijing 102211, China
  • Received:2021-08-14 Revised:2021-11-10 Online:2021-12-05 Published:2021-12-16
  • Supported by:
    This work is supported by Science and Technology Project of SGCC(Research on Channel Self-alignment Technology of SiC MOSFET, No.5455GB190011)

摘要: 基于本团队自研并金属封装的1 200V 20A SiC MOSFET器件,开展了器件参数分散性对并联组件均流的影响研究。首先引入器件偏离度和变异系数,分析了三线法和两线法测试平台对器件阈值电压和导通电阻测试结果的影响,得出三线法对于本文的测试结果更加可靠且可测参数更多;基于三线法的测试平台,实验测试了器件的基本特征参数,包括阈值电压、导通电阻、跨导等,并分析了30只器件的分散性,结果表明测试器件跨导的一致性较好,而阈值电压和导通电阻的偏离度较大;最后,以阈值电压和导通电阻为研究对象,选择了器件两参数相近与分散性较大的SiC MOSFET进行并联双脉冲实验,在排除了测试回路寄生参数的基础上,通过实验和仿真对比验证了导通电阻及阈值电压对器件并联均流的影响,结果表明阈值电压对于并联系统开关前后瞬态过程的均流影响较大,阈值电压较小的器件将承担更大的过冲电流,影响并联系统的可靠性;相比开关瞬态过程,导通电阻则是对稳态后的均流影响更大,导通电阻较小的器件将承担更大的电流,影响支路器件的可靠性。

关键词: SiC MOSFET, 分散性, 偏离度, 变异系数, 并联均流

Abstract: Based on the 1 200V 20A SiC MOSFET developed by our team, this paper studies the influence of device parameter dispersion on current sharing of parallel components. Firstly, the deviation degree and coefficient of variation of the device are introduced, and the influence of the three wire method and the two wire method test platform on the test results of the device threshold voltage and the on resistance are analyzed. The conclusion shows that the three wire method is more reliable and has more parameters to be measured. Based on the test platform of the three wire method, the basic characteristic parameters of the device are tested, including threshold voltage, on resistance, transconductance, etc, and the dispersion of 30 devices are analyzed. Finally, the threshold voltage and on resistance are taken as the research objects of parallel current sharing. SiC MOSFETs with similar device characteristic parameters and large dispersion are selected to carry out parallel double pulse experiment. On the basis of eliminating the parasitic parameters of the test circuit through the experiment, the influence of the on resistance and threshold voltage on the device parallel current sharing are verified. The results show that the threshold voltage has a great influence on the current sharing of the transient process before and after switching, and the devices with smaller threshold voltage will bear greater overshoot current, which will affect the reliability of the parallel system; Compared with the switching transient process, the on resistance has a greater impact on the current sharing after steady-state. The devices with smaller on resistance will bear greater current and affect the reliability of branch devices.

Key words: SiC MOSFET, dispersion, deviation degree, coefficient of variation, parallel current sharing