液体介质微/纳秒脉冲放电的特性与机理：现状及进展

李元; 温嘉烨; 李林波; 郜晶; 石亚轩; 刘志濠; 张冠军

doi:10.11884/HPLPB202133.210190

液体介质微/纳秒脉冲放电的特性与机理：现状及进展

doi: 10.11884/HPLPB202133.210190

西安交通大学电力设备电气绝缘国家重点实验室，西安 710049

基金项目: 国家自然科学基金项目（51607139，11635004）

详细信息

作者简介:
李　元（1984—），男，博士，副教授，主要从事液相放电基础与应用研究

通讯作者:
张冠军（1970—），男，博士，教授，主要从事电力设备状态评估、放电等离子体特性及应用研究

中图分类号: TM85
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- 文章访问数: 1993
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- 被引次数: 0
出版历程
- 收稿日期: 2021-05-18
- 修回日期: 2021-06-10
- 网络出版日期: 2021-06-11
- 刊出日期: 2021-06-15

Characteristics and mechanisms of streamer discharge in liquids under micro/nano-second pulsed voltages: status and advances

State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an 710049, China

摘要

摘要: 液相放电是高电压与绝缘技术领域持续的研究热点，深入理解微/纳秒脉冲放电的特性与机理有利于促进液相放电在电气装备设计优化、深远海勘探、先进材料制备等前沿领域的创新与突破。总结梳理了近年来液体介质微/纳秒脉冲流注放电特性与机理研究的进展，从放电模式与转化、分叉行为、击穿过程等方面阐释了流注放电的基础特性，归纳了液体电导率、压强、溶解气体、杂质与添加剂等物性参数对流注放电特性的影响规律，分析了液体介质流注放电起始与发展机制（包括气泡理论、液相直接碰撞电离、场致分子电离、电致伸缩效应等）及其适用范围。在此基础上，展望了液相放电领域的发展方向和面临的挑战，为相关领域的基础研究和工程应用提供参考。
- 液体介质 /
- 微秒脉冲 /
- 纳秒脉冲 /
- 流注放电 /
- 场致分子电离 /
- 电致伸缩
Abstract: The studies on discharges in liquid dielectrics have been continuously gaining great attentions in the field of high voltage and insulation engineering. Profound understandings of the characteristics and mechanism of micro/nano-second pulsed discharge in liquids are prerequisites to the innovation and breakthrough of various cutting-edge applications, e.g., optimized electrical equipment design, deep ocean explorations, advanced material synthesis. In this review, we summarize the recent progress in the investigations of characteristics and mechanisms of micro/nano-second pulsed streamer discharge in liquid dielectrics. Fundamental characteristics of streamer discharge are elucidated including discharge modes and transition, branching characteristic, and breakdown. The contributing factors on the streamer characteristics, such as liquid conductivity, pressure, dissolved gas, impurities and additives, are analyzed. Prevailing mechanisms of initiation and propagation of streamer discharge in liquids as well as their application scenarios are discussed, including bubble theory, direct impact ionization, field molecular ionization, electrostriction, etc. Further, we expect the prospects and challenges of liquid discharge to enlighten fundamental researches and engineering applications in the relevant fields.
- liquid dielectrics /
- micro-second pulse /
- nano-second pulse /
- streamer discharge /
- field molecular ionization /
- electrostriction

HTML全文

图 1 非极性液体中流注放电的四类典型模式^[4]

Figure 1. Four typical modes of streamer discharges in nonpolar liquids^[4]

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图 2 水中流注放电产生气泡的半径-时间演化规律^[29]

Figure 2. Bubble radius as a function of time since bubble formation in streamer discharge^[29]

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图 3 变压器油中正负极性流注分叉的光学图像与发展模型^[39-40]

Figure 3. Optical images and propagation models of positive and negative streamers branching in transformer oil^[39-40]

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图 4 变压器油中流注分叉三维仿真^[44]

Figure 4. 3D simulation of streamer branching in transformer oil^[44]

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图 5 考虑杂质颗粒影响的油中流注分叉过程（二维）^[45]

Figure 5. Streamer branching process in transformer oil due to impurity (2D)^[45]

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图 6 不同电压下水中放电模式与电导率的关系^[60]

Figure 6. Correlation between discharge modes and water conductivity under different voltages^[60]

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图 7 不同压强下变压器油中流注放电图像^[65]

Figure 7. Image of streamer discharge in transformer oil under different pressure^[65]

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图 8 水中正极性流注放电发展过程（σ＝90 μS/cm）^[60]

Figure 8. Propagation of positive streamer in water (σ＝90 μS/cm)^[60]

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图 9 脉冲电压下绝缘油中流注放电的发展过程^[83]

Figure 9. Simulations of streamer development in transformer oil under pulsed voltages^[83]

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图 10 电致伸缩效应诱导液体电离的机制^[91]

Figure 10. Schematic of electrostriction-induced liquid ionization^[91]

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