基于极化去极化电流法的水树老化XLPE电缆界面极化特性分析  

Interface Polarization Characteristics of Water Tree Aged XLPE Cables Based on Polarization and Depolarization Current Method

作　　者：尹游 周凯[1] 李诗雨 陈泽龙[1] 张福忠[1] Yin You;Zhou Kai;Li Shiyu;Chen Zelong;Zhang Fuzhong(College of Electrical Engineering Sichuan University,Chengdu 610065 China)

机构地区：[1]四川大学电气工程学院,成都610065

出　　处：《电工技术学报》2020年第12期2643-2651,共9页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(51477106)。

摘　　要：为实现对水树老化交联聚乙烯(XLPE)电缆进行准确、快速的绝缘状态诊断,该文基于极化去极化电流法(PDC)研究水树老化电缆极化过程中电导电流的变化,分析因水树区域电导率与相对介电常数的变化导致的“水树-XLPE”界面极化特性。通过获取不同老化时间的电缆样本并进行了PDC测试,提取电缆样本的电导电流,分析“水树-XLPE”的界面极化特性及其对极化去极化电流测试的影响。研究结果表明:不同测试电压下水树老化电缆的电导率呈现出非线性,极化过程中老化样本的电导电流呈现出先增大后逐渐衰减至稳定值的趋势,且随着老化时间的增加,这一趋势也越明显。分析认为,测试过程中由于水树区域电导率与相对介电常数发生变化,导致“水树-XLPE”界面极化电流存在先增大后减小至稳定值的趋势,从老化电缆的极化去极化电流中提取的电导电流存在峰值,电缆水树老化程度越严重,这一峰值也越大。In order to realize effective and fast insulation diagnosis of water tree aged cross-linked polyethylene(XLPE)cables,this paper investigated the change of conduction current of water tree aged cables in polarization process and analyzed the interface polarization characteristics of“water tree-XLPE”due to the variation of relative dielectric constant and conductivity of water tree region.Water tree aged XLPE cables with different aging time were obtained,and the short-time polarization and depolarization current(PDC)tests were performed on these samples.Conduction currents of aged cables were extracted to analyze the“water tree-XLPE”interface polarization and its impacts on the PDC tests.According to the results,the conductivity of water tree aged cables is nonlinear under different voltages.Conduction currents of aged cables in polarization process increase first and then decay to a stable value,and this trend becomes more obvious as the aging time increases.Analysis shows that the variation of conductivity and the relative dielectric constant in the water tree region lead to the peak value of conduction current of aged cables extracted from PDC tests due to the interface polarization,and this value is larger with more severe deterioration of water tree aged cables.

关 键 词：交联聚乙烯电缆 水树老化 绝缘诊断 极化去极化电流 界面极化 

分 类 号：TM247[一般工业技术—材料科学与工程]