Surface flashover in liquid nitrogen

1999 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.99CH36319) Pub Date : 1999-10-17 DOI:10.1109/CEIDP.1999.807890

M. Butcher, Andreas A. Neuber, H. Krompholz, L. L. Hatfield

{"title":"Surface flashover in liquid nitrogen","authors":"M. Butcher, Andreas A. Neuber, H. Krompholz, L. L. Hatfield","doi":"10.1109/CEIDP.1999.807890","DOIUrl":null,"url":null,"abstract":"The use of cryogenic high voltage components to achieve higher energy densities is limited by virtually unknown insulator characteristics for cryogenic conditions. Using a fast coaxial setup, the flashover phenomena of dielectric test samples (Lexan, Alumina) immersed in liquid nitrogen are measured with optical and electrical diagnostics with nanosecond time resolution. The flashover voltage reaches a maximum of 30 kV for a 1.75 mm gap after 3 shots, and averages to about 10 kV after conditioning. Three phases in the discharge development can be distinguished: Phase 1 is a rapid current rise to the mA-regime, with several current spikes with amplitudes of less than 5 mA and durations of typically 20 ns. This phase lasts up to several 100 ns. Phase 2 is characterized by a rapid ionization with a current rise to the impedance limited value of several 100 A of phase 3 in a few nanoseconds. Waveforms of the luminosity follow the ones of the current in general. The physical mechanisms leading to this development, and the difference to the flashover phenomena in vacuum, are discussed qualitatively.","PeriodicalId":267509,"journal":{"name":"1999 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.99CH36319)","volume":"528 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"1999-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"1999 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.99CH36319)","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/CEIDP.1999.807890","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}

引用次数: 0

Abstract

The use of cryogenic high voltage components to achieve higher energy densities is limited by virtually unknown insulator characteristics for cryogenic conditions. Using a fast coaxial setup, the flashover phenomena of dielectric test samples (Lexan, Alumina) immersed in liquid nitrogen are measured with optical and electrical diagnostics with nanosecond time resolution. The flashover voltage reaches a maximum of 30 kV for a 1.75 mm gap after 3 shots, and averages to about 10 kV after conditioning. Three phases in the discharge development can be distinguished: Phase 1 is a rapid current rise to the mA-regime, with several current spikes with amplitudes of less than 5 mA and durations of typically 20 ns. This phase lasts up to several 100 ns. Phase 2 is characterized by a rapid ionization with a current rise to the impedance limited value of several 100 A of phase 3 in a few nanoseconds. Waveforms of the luminosity follow the ones of the current in general. The physical mechanisms leading to this development, and the difference to the flashover phenomena in vacuum, are discussed qualitatively.

查看原文本刊更多论文

液氮表面闪络

低温高压元件的使用，以实现更高的能量密度是有限的，几乎未知的绝缘体特性的低温条件。采用快速同轴装置，对浸在液氮中的介质测试样品(Lexan，氧化铝)的闪络现象进行了纳秒级时间分辨率的光学和电学诊断。3次射击后，1.75 mm间隙内闪络电压最高可达30 kV，调节后平均约为10 kV。放电发展的三个阶段可以区分:阶段1是电流快速上升到mA状态，有几个振幅小于5 mA的电流尖峰，持续时间通常为20 ns。这一阶段持续长达100纳秒。相2的特点是快速电离，电流在几纳秒内上升到相3的阻抗限制值几个100a。光度的波形一般遵循电流的波形。定性地讨论了导致这一发展的物理机制，以及与真空中闪络现象的区别。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

1999 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.99CH36319)

自引率

0.00%

发文量