油纸绝缘热老化过程中含水量变化趋势及水分转移规律  

Moisture Content Variation and Transfer of Oil-paper Insulation During Thermal Aging Process

作　　者：廖瑞金[1] 尹建国[1] 杨丽君[1] 巩晶[1] 唐超[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030

出　　处：《高电压技术》2010年第4期828-834,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724505-1)~~

摘　　要：根据某一具体时刻的油中含水量(即水的体积分数)来估算纸中含水量误差较大,且根据油、纸的含水量绝对值来进行变压器状态评估及受潮分析不全面。为此,在110°C和130°C下设计了初始含水量分别为1%、3%、5%的绝缘纸在矿物油中的加速热老化试验。系统研究了老化过程中绝缘纸平均含水量、油中含水量及油纸绝缘系统总含水量变化趋势;通过分析系统总含水量的变化及绝缘纸内部水分分布情况,探讨了油纸绝缘的水分转移规律;分析了老化过程中油中水分与纸中水分的关系。结果表明:老化过程中油中水分、纸中水分及系统总含水量均是波动的,且3者的波动幅度相互之间有较好的正相关性;初始含水量较高(3%、5%)时,油纸绝缘系统与外部氮气环境之间的水分转移起主导作用,初始含水量较低(1%)时,水分主要在系统内部油、纸二相间转移;老化过程中油中水分与纸中水分不能构成函数关系。因此提出应根据整个老化过程中油、纸及油纸绝缘系统总含水量3者整体上的波动趋势和波动幅度来进行变压器状态评估及受潮分析。That the moisture content in oil is used to estimate the moisture content in paper has a great error,and that the absolute value of moisture content in oil and paper is used to assess insulation state and insulation damp is incomplete. We designed a aging test,in which the insulating papers with the initial moisture contents of 1%,3%,5% were aged in mineral oil at 110℃ and 130℃,respectively. The variation trends of water content in paper,in oil and total moisture content of oil-paper insulation system during the aging process were studied. Moreover,the rule of moisture transfer of oil-paper insulation system was discussed through analyzing the variation of total moisture content of oil-paper insulation system and the distributed state of moisture inside insulating papers,and the relationship of moisture content between in oil and in paper was analyzed. The results indicate that,the water content in oil,in paper and total moisture content of oil-paper insulation system are fluctuant during the aging process,the fluctuation amplitude among the three has a good positive correlation; the transfer of moisture between the oil-paper insulation system and the external nitrogen environment plays a leading role when the moisture content is higher （3%,5%）,and the transfer of moisture between oil and paper plays a leading role when the moisture content is lower （1%）;The moisture content in oil and paper can not constitute function. Therefore,to make the assessment insulation state and insulation damp effect more accurate,it is suggested that the global relationship of the fluctuations trend among oil ,paper water content and the total moisture content of oil-paper insulation system and the fluctuation amplitude should be take into consideration.

关 键 词：水分 油纸绝缘 热老化 变压器 波动 转移 

分 类 号：TM855[电气工程—高电压与绝缘技术]