打浆度对纤维素绝缘纸性能的影响  

Influence of Beating Degree on Properties of Cellulose Insulation Paper

作　　者：廖瑞金[1] 鄢水强 杨丽君[1] 袁媛[1] 黄游宇 郑小玲 LIAO Ruijin;YAN Shuiqiang;YANG Lijun;YUAN Yuan;HUANG Youyu;ZHENG Xiaoling(State Key Laboratory of Power Transmission Equipment & System Security and New Technology,Chongqing University, Chongqing 400044,China;Hunan Guangxin Technology Co.,Ltd.,Shaoyang 422900,China;Suzhou Power Supply Branch, State Grid Jiangsu Electric Power Co.,Ltd.,Suzhou 215000,China)

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]湖南广信科技股份有限公司,邵阳422900 [3]国网江苏省电力有限公司苏州供电分公司,苏州215000

出　　处：《高电压技术》2018年第12期3777-3783,共7页High Voltage Engineering

基　　金：国家自然科学基金(51437001);国家创新研究群体基金(51321063);中国电力科学研究院科技项目(GY71-14-001)~~

摘　　要：打浆度是综合反映绝缘纸纤维素被切断、润胀和纤维细化的程度,直接影响电力变压器中油纸复合绝缘性能的重要指标。为探究打浆度对油–纸绝缘系统性能的影响规律,在实验室制备了5个不同打浆度的绝缘纸手抄片,浸油后形成油纸复合绝缘样品,测试了不同打浆度油纸绝缘样品的机械性能和交/直流介电性能。利用扫描电子显微镜对绝缘纸表面和断面的纤维进行了微观形貌观测,研究了现有条件下打浆度对绝缘纸机械性能影响,并结合典型的油纸复合绝缘“纸带”模型,分析了打浆度对绝缘纸绝缘性能的影响规律。结果表明:随着打浆度的增加,纤维的分丝帚化程度增加,并逐渐变短变细,纤维分布更均匀,纤维间连接变紧密,但随着打浆度的持续上升,后期纤维质量受损严重,因此使得绝缘纸机械强度、电气强度呈先上升后下降趋势;内部陷阱能级先降低后增高,相对介电常数和介质损耗先减小后增大。综合认为,5个打浆度中,85°SR打浆度时绝缘纸具有最优的绝缘性能。Beating degree of cellulose insulation paper is a comprehensive reflection of the fiber being cut, swelled and fibrillated, and it has a direct impact on insulation performance of oil-paper composite insulation in power transformers. In order to study the influence of beating degree on the insulation properties of insulation paper, paper with five beating degrees was prepared and immersed with 25# mineral oil, then the mechanical properties, breakdown strength, and dielectric properties of paper were tested. The microstructure of fiber morphology was observed by SEM and the effect of beating degree on the mechanical strength was researched. By using the tape model of oil impregnated paper, the influence mechanisms of beating degree on electrical insulation properties were analyzed. The research results show that, as the beating degree increases, the fibers gradually become shorter and thinner, and the connection between fibers get enhanced, wheras the fibers are severely damaged while the beating degree is too high. Therefore, the mechanical strength and electrical strength present a trend of rise firstly and then fall with the increase of beating degree. In addition, the energy level inside paper decreases firstly and then increases, and the trends of permittivity and dielectric loss are as the same as energy level. In summary, it is considered that paper with 85°SR beating degree has better insulation performance compared with other beating degrees.

关 键 词：打浆度 绝缘纸 介电性能 微观形貌 陷阱能级 

分 类 号：TM21[一般工业技术—材料科学与工程]