摘要
水树是交联聚乙烯(XLPE)电缆老化的一种重要形式,基于短时极化/去极化电流(PDC)测试方法,分析了水树缺陷引起的极化/去极化过程中的超低频介损不对称现象。实验模拟电缆实际运行中遇到的老化情况,对实验室短、长电缆进行人工加速老化,分析电缆水树老化前后的低频介质损耗特性。为了进一步说明该现象,引入了超低频介损不对称系数(Kas)量化不对称程度,构建电缆等效电路模型协同Comsol仿真,对其加以分析。结果表明:水树老化会使得电缆极化超低频介损大于去极化超低频介损,呈现明显的不对称性。将电缆等效模型中去极化电路绝缘提升,Comsol仿真显示通过水树区域的电流减小。
Water tree is an important ageing form of XLPE cables. The asymmetry phenomenon of ultra-low frequency dielectric loss during polarization and depolarization process caused by water tree defects was analyzed basing on short-term polarization and depolarization current test method（PDC）. To simulate the ageing situation of cables during actual operation, the artificial accelerated ageing experiments were conducted on the short and long cables in the laboratory, and the ultra-low frequency dielectric loss characteristics of the cables before and after water tree ageing were analyzed. To further illustrate this phenomenon, the asymmetry coefficient（Kas） of ultra-low frequency dielectric loss was introduced to quantify the degree of asymmetry. A cable equivalent circuit model was constructed and simulated by Comsol to analyze the phenomenon. The results show that the ultra-low frequency dielectric loss of cable during polarization is greater than that during depolarization after water tree ageing, which shows obvious asymmetry. After increasing the insulation of depolarization circuit in cable equivalent model, the Comsol simulation shows the current passed through the water tree region decreases.
作者
黄科荣
周凯
黄明
龚军
李明志
HUANG Kerong;ZHOU Kai;HUANG Ming;GONG Jun;LI Mingzhi(College of Electrical Engineering and Information Technology,Sichuan University,Chengdu 610065,China;Nanchang Power Supply Company of State Grid Jiangxi Electric Power Company,Nanchang 330012,China)
出处
《绝缘材料》
CAS
北大核心
2018年第9期36-40,47,共6页
Insulating Materials
基金
国家自然科学基金资助项目(51477106)
关键词
XLPE电缆
水树
极化/去极化
超低频介损
不对称性
XLPE cable
water tree
polarization and depolarization
ultra-low frequency dielectric loss
asymmetry
作者简介
黄科荣（1993-），男（汉族），四川内江人，硕士生，主要从事高电压技术与应用的研究；;周凯（1975-），男（汉族），四川宜宾人，教授，主要从事电缆状态监测及固体电介质的研究。
