220 kV交联聚乙烯电缆接头缺陷处电场畸变特性分析  

Analysis of Electric Field Distortion Characteristics at Defects of 220 kV XLPE Cable Joints

作　　者：聂颖 罗日成[1] 王卫 华园园 NIE Ying;LUO Richeng;WANG Wei;HUA Yuanyuan(College of Electrical and Information Engineering,Changsha University of Science and Technology,Changsha 410114,China;Hunan Yi Yi Electric power Co.,Ltd.,Changsha 410114,China)

机构地区：[1]长沙理工大学电气与信息工程学院,长沙410114 [2]湖南一一电力有限公司,长沙410114

出　　处：《电力学报》2024年第5期377-388,共12页Journal of Electric Power

基　　金：湖南省教育厅科研基金项目(23A0240);长沙市自然科学基金项目(kq2402023)。

摘　　要：电缆接头是电缆的核心部件,在安装、运行中其内部都可能会出现缺陷,这些缺陷在长期高压运行和复杂环境的影响下,会形成影响接头内绝缘材料的性能的潜在威胁。为探究缺陷情况下电缆接头内部电场畸变特性,通过COMSOL Multiphysics软件搭建了220 kV电缆接头三维仿真模型,设置了单气隙、单水珠、单个铜杂质、水珠串、双气隙和气隙‒铜杂质复合等缺陷模型,分析其缺陷的大小和分布对接头内部电场的影响。结果表明:单气隙和单水珠缺陷离应力锥根部越近,电场畸变越严重;水珠串缺陷中各个水珠与应力锥根部距离越近,造成的电场畸变程度就越大,但除去与应力锥根部直接接触的水珠,其它水珠表面的最大畸变场强与水珠间距呈负相关;双气隙缺陷间距越大,造成的电场畸变越大;气隙‒铜杂质复合缺陷在远离应力锥根部后,最大畸变场强出现在杂质缺陷附近。研究结果可以掌握各类缺陷下电缆接头内部的电场畸变规律,找出容易发生局部放电的位置,为工程实际中电缆接头防护、绝缘缺陷检测及缺陷类型判断提供理论参考。The cable gland is the core component of the cable,and its internal defects may appear in installation and operation,which will pose a great threat to the performance of the insulating material in the joint under the influence of long-term high-voltage operation and complex environment.In order to explore the distortion characteristics of the electric field inside the cable joint under defective conditions,a 3D simulation model of the 220 kV cable joint is built by COMSOL Multiphysics,and the single air gap,single water droplet,individual copper impurities,water bead string,double air gap and air-copper impurity composite defects are set up,and the influence of the size and distribution of the defects on the electric field inside the joint is analyzed.The results show that the closer the single air gap and single water droplet defects are to the root of the stress cone,the more serious the electric field distortion is.The closer the distance between each water bead and the root of the stress cone in the defect of the water bead string,the greater the degree of electric field distortion caused,but except for the water droplets in direct contact with the root of the stress cone,the maximum distortion field strength of the surface of other water droplets is negatively correlated with the spacing of the water droplets.The larger the spacing of the double air gap defects,the greater the distortion of the electric field.The maximum distortion field strength of the air-gap-copper impurity composite defect occurs near the impurity defect after it is far away from the root of the stress cone.The research results can grasp the distortion law of electric field inside cable joints under various defects,find out the location where partial discharge is easy to occur,and provide a theoretical reference for cable joint protection,insulation defect detection and defect type judgment in engineering practice.

关 键 词：高压电缆 交联聚乙烯 电缆接头 复合缺陷 电场畸变 电场仿真 

分 类 号：TM854[电气工程—高电压与绝缘技术]