XLPE电缆水树枝老化的介损检测方法分析及试验研究  

Analysis and Experimental Study on Test Methods of Dielectric Loss to Examine Water Tree Aging in XLPE Cable

作　　者：李鹏[1] 董雪峰[1] LI Peng;DONG Xuefeng(Zhengzhou Electric Power Technical College,Zhengzhou,Henan 450000,China)

机构地区：[1]郑州电力高等专科学校

出　　处：《东北电力技术》2019年第12期25-28,共4页Northeast Electric Power Technology

基　　金：郑州市科技局普通科技攻关项目(131PPTGG427)

摘　　要：介绍了介损正切(tanδ)与交联聚乙烯(XLPE)电缆绝缘水树枝老化的关联性,分析了工频电压下电桥法、0.1 Hz超低频电压下、串联谐振条件下现场测量XLPE电缆tanδ的适用性及优缺点。对比发现,0.1 Hz超低频电压下测量tanδ的方法得到广泛研究和认同,但超低频时tanδ值不能表征XLPE电缆工频电压下的绝缘状况;工频电压下用电桥测量tanδ能够反映XLPE电缆真实绝缘状况,电桥容量较小限制了该方法使用范围;串联谐振装置测量tanδ能基本反映XLPE电缆真实绝缘状况,配套设备体积大制约了其应用。给出用工频介损测试仪测量tanδ的结果,初步表明在配电电压下、长度较短时用电桥法测量tanδ,发现XLPE电缆绝缘内部存在严重水树枝老化缺陷。It introduces the relevance between tangent of dielectric loss(tanδ)to aged insulation due to water treeing of XLPE cables.It analyzes the applicability,merits and demerits to test tanδin XLPE cable insulation under field conditions,i.e.,power frequency voltage using dielectric loss bridge,0.1 Hz very-low frequency voltage and frequency series resonance.The compared results show that the method to test tanδunder 0.1 Hz very-low frequency voltage is widely researched and approved,but the test value cannot represent true insulation condition of XLPE cable under power frequency voltage.Using dielectric loss bridge to test tanδunder power frequency voltage can truly reflect insulation condition of XLPE cable,but the lesser capacity of bridge restrict its range of application.Test tanδunder frequency series resonance condition can fundamentally reflect insulation condition of XLPE cable,but the larger corollary equipment of frequency series resonance testing system restrict this method’s application.The test result under field condition is given using dielectric loss bridge.The result indicates that tanδvalue tested by dielectric loss bridge is effective to find serious defect of aged insulation due to water treeing under condition of distribution voltage and cable being shorter.

关 键 词：交联聚乙烯电缆 水树枝老化 TANΔ 

分 类 号：TM75[电气工程—电力系统及自动化]