绝缘护套包覆对500kV输电线路导线与杆塔间空气间隙击穿特性的影响  

Electrical Breakdown Characteristics of Air Gap Between Conductor and Tower Covered by Insulation Sheath in 500 kV Transmission Line

作　　者：陈杰 刘洋 周立 周志成 梅红伟[2] 谢天喜 

机构地区：[1]江苏省电力公司电力科学研究院,南京211100 [2]清华大学深圳研究生院,深圳518055

出　　处：《高电压技术》2015年第7期2315-2320,共6页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209406);国家自然科学基金(51307094)~~

摘　　要：为有效解决输电线路风偏放电问题,对输电线路及金具进行绝缘包覆以提高放电击穿电压,仿真和试验研究了绝缘护套包覆对500 k V输电线路模拟杆塔中导线与塔身间空气间隙击穿特性的影响。试验过程中,对单导线及4分裂导线分别施加1 min 1.1倍工频相电压(318 k V),通过改变导线与杆塔间距研究不同间距下的耐压情况。仿真结果表明,导线包覆绝缘护套后,其表面最大场强随间距增大而降低;裸导线空气间隙击穿电压与间隙距离呈线性关系;单导线包覆绝缘护套后可缩短13.6%的间隙距离,4分裂导线包覆绝缘护套可缩短9.3%的间隙距离;击穿点均位于绝缘盒连接处,其原因是此处以室温硫化硅橡胶填补缝隙密封时施工密封不严。绝缘护套包覆导线及金具措施可有效提高输电线路导线与杆塔间空气间隙击穿特性,但应严格控制施工工艺以提高实际效果。In order to effectively solve the windage yaw discharging problem of transmission lines, we covered transmission lines and hardware firings by insulation sheath to improve discharging breakdown voltage, and studied the influences of insulation sheath on the electrical breakdown characteristics of air gap between conductors and tower for 500 kV transmission line tower. During experiments, we applied AC 318 kV voltage to the conductors for 1 min, and studied the withstand voltage under different gaps through changing the distance between conductor and tower. Simulation results show that the maximum electric field of conductors decreases with the length of air gap. At the same time, electric breakdown voltage is in linear relationship with gap distance for bare conductor. When 318 kV voltage was applied, the distance of electric breakdown decreased by 13.6% for single conductor and 9.3% for quad-bundle conductor covered by insulator sheath. The breakdown points were located in different sheath connection space which was filled with room temperature vulcanized silicone rubber. It is concluded that conductors covered by insulation sheath can effectively improve the electric breakdown characteristics of air gap between the lines and the tower. However, the construction process should be strictly controlled in order to improve the actual results.

关 键 词：输电线路 风偏 间隙 击穿 绝缘护套 导线 室温硫化硅橡胶 

分 类 号：TM75[电气工程—电力系统及自动化]