FC-72介质液态、气态及两相态工频击穿特性研究  

Study on Power Frequency Breakdown Characteristic of FC-72 Medium in Liquid,Gaseous and Two-phase State

作　　者：莫申扬 张金强 李学宝[1] 毛塬 赵志斌[1] 崔翔[1] MO Shenyang;ZHANG Jinqiang;LI Xuebao;MAO Yuan;ZHAO Zhibin;CUI Xiang(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《高压电器》2021年第5期77-83,92,共8页High Voltage Apparatus

基　　金：国家电网有限公司总部科技项目资助(5209502000D5)。

摘　　要：相变冷却技术逐渐成为高压功率电力电子器件散热瓶颈的解决方案。但在高压应用场景中,由气泡引发的绝缘问题需要重点关注。针对相变冷却的沸腾特征,掌握制冷剂液态、气态以及两相态的绝缘特性是开展相变冷却技术绝缘分析的基础,而现有研究尚没有系统性的制冷剂多相态绝缘特性测试方法。因此,文中研制了用于制冷剂多种相态工况的绝缘实验装置,首次实现了低沸点液体蒸汽的介电强度测试,进而提出了制冷剂蒸汽及两相态环境的击穿实验方案。利用FC-72制冷剂,对其液态、气态及两相态展开了系统性的击穿特性研究,获得了FC-72蒸汽在多种气压下的介电强度,以及其两相态下的击穿测试结果。结合气泡在电场下的行为特性,分析了两相态环境下的击穿机制。最终,形成了以蒸汽介电强度为依据的两相态间隙绝缘阈值评估方法。Two-phase cooling technology is gradually becoming a solution for the heat dissipation bottleneck of high voltage power electric and electronic device.However,in case of high voltage application,the issue of insulation due to the boiling bubble needs special attention.As for the boiling characteristic in the two-phase cooling condition,mastering the insulation characteristic of refrigerants in liquid,gaseous and two-phase condition is the base for the development of insulation analysis of the two-phase cooling technology.However,the existing study does not yet have systematic method for multi-phases insulation test of the refrigerants.Therefore,the insulation experimental device for multiple phase conditions of refrigerants is developed and the dielectric strength test for the liquid vapor of low boiling liquid is achieved for the first time.Then,the breakdown experimental scheme for the vapor and two-phase flow of refrigerant is proposed.The systematic breakdown characteristic study of the liquid,gaseous and two-phase condition is developed by the use of FC-72 refrigerant.The dielectric strength of FC-72 vapor under various pressures and the breakdown test result at its two-phase condition is obtained.The breakdown mechanism at a two-phase condition is analyzed with combination of the behavioral characteristic of the bubble at electric field.Finally,the evaluation method of insulation threshold of two-phase gap with vapor dielectric strength as base is formed.

关 键 词：FC-72 蒸汽 两相流 介电强度 击穿 气泡 相变冷却 

分 类 号：TB66[一般工业技术—制冷工程] TM721.1[电气工程—电力系统及自动化]