变压器油纸绝缘热老化过程中铜类产物生成规律及其危害  

Formation Laws of Copper Products and Their Harms During Transformer Oil-Paper Insulation Thermal Aging Process

作　　者：廖瑞金[1] 郝建[1,2] 杨丽君[1] 尹建国 朱孟兆[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400044 [2]重庆电力科学试验研究院,重庆401123 [3]湘潭电力局,湘潭411100

出　　处：《电工技术学报》2012年第10期52-59,共8页Transactions of China Electrotechnical Society

基　　金：国家重点基础研究发展计划项目(973项目)(2009CB724505-1);输配电装备及系统安全与新技术国家重点实验室自主研究项目(2007DA10512708103)

摘　　要：变压器内部铜材料受腐蚀而引起变压器故障的现象日渐受到国内外研究学者和工程人员的广泛关注。本文将国内变压器广泛使用的油纸绝缘材料(25#环烷基变压器油、25#石蜡基油、纤维素绝缘纸)和电工用铜组成含铜与不含铜油纸绝缘试品,开展了不同组合油纸绝缘试品的热老化特性研究,运用X射线光电子能谱(XPS)表征了绝缘纸表面沉积产物的存在形态,分析了绝缘油中和绝缘纸表面铜类产物含量的变化规律,并通过原子力显微镜(AFM)研究了铜类产物对绝缘纸表面粗糙度的影响。结果表明:油中铜类产物的存在加速了绝缘油的老化,降低了绝缘油的击穿电压;绝缘油中溶解的铜类产物含量随老化时间呈现先增大后减小的趋势;绝缘油中未出现油泥前,25#环烷基变压器油中溶解的铜类产物含量低于老化同期的25#石蜡基油;铜类产物会向绝缘纸表面沉积,离铜片最近的绝缘纸表面沉积的铜类产物含量最大;XPS结果表明在绝缘纸表面沉积了铜和氧化铜;铜类产物的存在增大了绝缘纸表面粗糙度。Transformer failure caused by the corrosion of copper material in transformer attracts great attention of domestic and foreign researchers and engineers.25 # naphthenic transformer oil,25 # paraffin-based transformer oil,kraft paper and copper are used to compose four combinations of oil-paper insulation samples.The thermal characteristic of four combinations of oil-paper insulation samples are compared,the existence form of deposition products on insulating paper surface is characterized by X-ray photoelectron spectroscopy（XPS）,the content variations of copper products dissolved in insulating oil and deposited on paper surface are analyzed,and the effects of copper products on the paper surface roughness are studied by atomic force microscope（AFM）.The results show that the content of copper products dissolved in insulating oil increases with aging time at first and then decrease.The copper products can accelerate the aging rate of insulating oil and reduce its breakdown voltage.Before the oil sludge appearing,the content of copper products dissolved in 25 # naphthenic transformer oil is less than that in 25 # paraffin-based transformer oil after aging the same time.The copper products can deposit on the insulating paper surface and the largest content of copper products depositing on the insulation paper surface is the paper which is the most recent away from the copper.XPS results show that there are copper and copper oxide depositing on the insulating paper surface.The copper products increase the insulating paper surface roughness.

关 键 词：变压器 油纸绝缘 铜类产物 X射线光电子能谱 原子力显微镜 粗糙度 

分 类 号：TM835[电气工程—高电压与绝缘技术]