电缆XLPE绝缘温度梯度对电树枝老化的影响研究  

Study on influence of temperature gradient of XLPE insulation on electrical tree

作　　者：鄂士平 刘东超[2] 熊慕文[2] 高森 E Shiping;LIU Dongchao;XIONG Muwen;GAO Sen(State Grid Hubei Electric Power Company,Wuhan 430077,China;Nanjing NARI Electric Co.,Ltd.,Nanjing 211102,China)

机构地区：[1]国网湖北省电力有限公司,湖北武汉430077 [2]南京南瑞继保电气有限公司,江苏南京211102

出　　处：《电气应用》2022年第9期28-32,共5页Electrotechnical Application

摘　　要：交联聚乙烯(XLPE)电力电缆是城市供电网络的重要环节,绝缘劣化导致的故障是威胁电缆长期稳定运行的重要因素。在运行工况下,电缆绝缘内会存在径向温度梯度,并可能影响绝缘内的电树枝劣化过程。研究XLPE温度梯度对电树枝生长的影响规律及机理,对提高电缆运行可靠性具有重要意义。选取XLPE试样及工频交流电压,研究了多个温度梯度下的电树枝生长趋势。结果表明,温度梯度的存在会促进电树枝的生长,而树枝形态也将随着温度梯度的存在而发生变化,由温度导致的电导率差异及电荷能量的变化是导致电树枝形态及生长速度差异的主要原因。Cross-linked polyethylene(XLPE)power cable is an important part of the power supply network in the city,and the failure caused by the insulation degradation is an important factor that threatens the long-term stable operation of cables.Under operating conditions,there is a radial temperature gradient within the cable insulation,which may affect the growth process of electrical tree.For XLPE,it is of great significance to study the influence mechanism of temperature gradient on the growth of electrical trees,and to improve the reliability of cable operation.The XLPE sample and AC voltage are selected to study the growth trend of electric trees under multiple temperature gradients.The results show that the presence of temperature gradients will promote the growth of electrical trees,and the morphology of trees will change with the presence of temperature gradients.The difference in electrical conductivity and the change in charge energy caused by temperature are the main reasons for the difference in morphology and growth rate of electrical trees.

关 键 词：XLPE 电力电缆 电树枝 温度梯度 树枝形态 树枝长度 

分 类 号：TM75[电气工程—电力系统及自动化]