基于PDC法的水树老化电缆绝缘诊断  

Insulation Diagnosis of Water-treed Cables Based on Polarization and Depolarization Current Method

作　　者：蔡钢[1] 刘曦[1] 濮峻嵩[1] 周凯[2] 黄明[2] 

机构地区：[1]四川电力科学研究院,成都610072 [2]四川大学电气信息学院,成都610065

出　　处：《绝缘材料》2016年第7期61-64,71,共5页Insulating Materials

基　　金：国家自然科学基金资助项目(51477106);国网四川省电力公司电力科学研究院科技项目(15H0558)

摘　　要：为对10 k V运行电缆的绝缘状态进行简单、快速诊断,基于极化-去极化电流(PDC)特征研究了针对电缆水树老化的绝缘诊断判据。采用高频高压水针电极法对电缆实验样品进行加速水树老化,使用显微镜定期观察不同老化时期样品中的水树形态,并统计水树长度,同时使用PDC测试平台对水树老化样品进行测试。利用测得的极化和去极化电流曲线求得电缆绝缘层的直流电导率和非线性系数,分析两参数随样品老化程度的变化趋势及规律。结果表明:根据直流电导率和非线性系数的变化能有效判别电缆绝缘中的水树老化问题。In order to diagnose the insulation condition of 10 kV power cables simply and rapidly, the diagnosis criterion based on polarization-depolarization current （PDC） characteristics for water-treed cables was investigated. The cable samples were performed accelerated water tree ageing experiment through water needle electrode method, and the morphology of water trees in the samples was observed by micro- scope, and then the length of water trees were counted. At the same time, the water-treed samples were tested by the PDC detection system. The DC conductivity and the non-linearity factor of cable insulation were acquired by the measured polarization and depolarization current curves, and the change tendency of the two parameters with the ageing condition of cables was analyzed. The results show that the water tree ageing problems in cable insulation can be assessed effectively via the change of DC conductivity and non-linearity factor.

关 键 词：交联聚乙烯电缆 水树 极化-去极化 直流电导率 非线性系数 

分 类 号：TM247[一般工业技术—材料科学与工程]