±800kV特高压直流输电线路的电位转移电流特性  

Characteristics of Potential Transfer Current of ±800 kV UHVDC Transmission Line

作　　者：刘凯[1,2] 吴田[1,2] 刘庭[1] 肖宾[1] 

机构地区：[1]中国电力科学研究院,武汉430074 [2]武汉大学电气工程学院,武汉430072

出　　处：《高电压技术》2013年第3期568-576,共9页High Voltage Engineering

基　　金：国家电网公司科技项目(SG09056)~~

摘　　要：为了确保±800kV特高压直流(UHVDC)输电线路带电作业过程中线路和作业人员的安全,对带电作业进入等电位过程中的电位转移电流特性进行研究有助于采取适当的防护措施。为此,采用光纤脉冲电流测量系统对进入±800kV特高压直流输电线路过程中的电位转移电流进行了测量,进入直流等电位过程中的电位转移电流脉冲最大幅值为149.98A,脉冲宽度为几十μs,正极性和负极性脉冲都存在。根据进入交直流线路等电位的特点,采用电磁分析软件研究了进入等电位过程中作业人员与极导线间的电位分布,计算了作业人员与极导线和杆塔等接地构件间的电容,根据这些参数建立了交直流线路进入等电位过程中的电位转移电流的分析模型,对特高压交流(UHVAC)与特高压直流线路的电位转移电流进行了计算。计算与测量结果表明特高压直流线路的电位转移电流远小于特高压交流线路,可以为特高压输电线路带电作业方法的选取提供参考。To ensure the safety of both lines and working staff while live working on ±800 kV ultra high voltage DC（UHVDC） transmission lines,studies of potential transfer current（PTC） in the process of live working entering into equal-potential status will contribute to adopting appropriate protections.Thus,we measured the PTC in live workings on ±800 kV UHVDC lines by using a fibre-optic pulsed-current measuring system.The PTC has a magnitude of 149.98 A and a pulse width of tens of μs,and it has both positive and negative polarity pulses.Taking the characteristics of shifting into equal-potential status into consideration,we investigated the potential distribution in the space between the worker and line by using an electromagnetic analysis software,and calculated the capacitance between workers and grounding structures,such as polarity conductors and towers.Based on the obtained parameters,analysis models of the PTC in the shifting process of both ultra high voltage AC（UHVAC） and UHVDC lines were established,and the PTC was calculated,respectively.The measurement and calculation results show that the PTC of UHVDC lines is much lower than that of UHVAC lines.

关 键 词：±800kV 特高压直流 UHVDC 特高压交流 UHVAC 输电线路 带电作业 电位转移电流 脉冲电流 仿真计算 光纤测量 

分 类 号：TM751[电气工程—电力系统及自动化]