覆冰水在自然环境下冻结过程中电解质晶释效应实验与分析  

Experiments and Analysis of Crystallization Effect During Transition of Freezing Water From Liquid Phase to Solid Phase in Natural Environment

作　　者：巢亚锋[1] 蒋兴良[2] 张志劲[2] 胡建林[2] 胡琴[2] 

机构地区：[1]湖南省电力公司科学研究院,湖南省长沙市410007 [2]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044

出　　处：《电网技术》2013年第2期539-544,共6页Power System Technology

基　　金：国家重点基础研究发展计划项目(973项目)(2009 CB724501;2009 CB 724502)~~

摘　　要：就覆冰水在由液态至固态相变过程中冰层中电导率的空间分布展开讨论,在自然环境下研究了不同电导率的液态水在相变过程中电解质晶释的物理过程。对相同体积、不同电导率的试品进行冰冻,通过测量得到覆冰水在由液态至固态的相变过程中,靠近冰层外表面空间的导电离子浓度最大的结果。分析了覆冰水在相态转变过程中冰层内部空间电导率分布出现差异的原因,揭示了融冰水电导率与覆冰水电导率差异的本质。提出了覆冰闪络时覆冰体电阻的表达式,指出了在分析覆冰绝缘子闪络特性时应考虑覆冰的晶释效应的影响。The spatial distribution of conductive ions within ice layer during the transition of freezing water from liquid phase to solid phase is discussed,and the physical process of the electrolyte crystallization during phase transition of freezing water with different conductivities in natural environment is researched.Freezing specimens with the same volume and different conductivities and then measuring frozen specimens,measurement results show that during the phase transition of freezing water from liquid phase to solid phase the maximum conductive ion concentration appears in the space near to outside surface of the ice layer.The reason causing the difference of conductivities in the inner space of the ice layer during the transition of freezing water from liquid phase to solid phase is analyzed,and the essence leading to the difference between the conductivity of melting ice water and freezing water is revealed.The expression of the volume resistance of ice coating during icing flashover is put forward,and it is pointed out that the influence of crystallization effect of ice coating should be considered during the analysis on flashover characteristics of ice-covered insulator.

关 键 词：覆冰水 相变 晶释效应 融冰水 绝缘子 覆冰闪络 

分 类 号：TM852[电气工程—高电压与绝缘技术]