±800 kV输电线路直流绝缘子串分布电导模型及其对电压和泄漏电流的影响研究  

Insulator String Conductance Distribution Model of±800 kV DC Transmission Line and Its Influence on the Voltage and Leakage Current

作　　者：曹晓斌[1] 陈友 唐平 朱军 严磊 CAO Xiaobin;CHEN You;TANG Ping;ZHU Jun;YAN Lei(Electric Engineering School of Southwest Jiaotong University,Chengdu 610031,China;State Grid Sichuan Electric Power Research Institute,Chengdu 610072,China)

机构地区：[1]西南交通大学电气工程学院,成都610031 [2]国网四川省电力公司电力科学研究院,成都610072

出　　处：《高压电器》2020年第5期86-93,共8页High Voltage Apparatus

基　　金：国网四川省电力公司科技项目(521997160025)。

摘　　要：直流绝缘子串泄漏电流不仅是绝缘子金具腐蚀的主要原因,同时也是在线监测的一项重要指标。为了研究直流绝缘子串上不同位置绝缘子金具上的泄漏电流的组成及分布特性,文中建立了直流绝缘子串三维有限元模型,研究了绝缘子串上金具对导线、大地,以及绝缘子金具之间的电导,分析了绝缘子金具处泄漏电流的影响因素及分布特性。结果表明:直流绝缘子串不同位置金具上的泄漏电流存在较大的差异;绝缘子金具泄漏电流分为沿面泄漏电流和空间泄漏电流,沿面泄漏电流沿着绝缘子串表面流动,空间泄漏电流的一部分在绝缘子金具、空气、杆塔、大地之间流动,另一部分在绝缘子金具、空气、均压环、导线之间流动;直流绝缘子串电压分布情况是分布电容和分布电导共同作用而形成的动态平衡状态。该研究成果可为绝缘子金具腐蚀、泄漏电流在线检测以及绝缘子串等效电路的研究提供参考。To analyze the composition and distribution characteristics of the leakage current in the insulator fittings in different positions of a DC insulator string,we established a three⁃dimensional finite element model of DC insula⁃tor string,calculated the mutual conductance of insulator fittings to transmission line and ground,and analyzed the influencing factors and distribution characteristics of the leakage current.The results show that there is a great differ⁃ence of leakage current in insulator fittings between different positions on the DC insulator string.The leakage cur⁃rent in insulator fittings consists of three parts—the first part flows from insulator fittings through air to ground,the second part flows from transmission line through air to insulator fittings,and the third part flows along the surface of insulator.The voltage distribution of the DC insulator string is in a dynamic equilibrium state produced by both dis⁃tributed capacitance and distributed conductance.The study may provide reference for the research on corrosion of insulator hardware,online detection of leakage current,and equivalent circuit of insulator string.

关 键 词：特高压直流 绝缘子 沿面泄漏电流 空间泄漏电流 金具腐蚀 

分 类 号：TM216[一般工业技术—材料科学与工程] TM75[电气工程—电工理论与新技术]