同塔双回特高压直流线路过电压研究

Study on Overvoltage in UHVDC Double-Circuit Transmission Lines on Same Tower

采用特高压双回直流线路同塔架设的方式,在很大程度上能够缓解特高压直流工程发展过程中输电走廊选址困难的问题。文章对双回特高压直流同塔架设的过电压沿线分布特性和最高水平进行了详细的仿真研究。对导线4种不同布置方案下的过电压沿线分布特性和最高水平进行了对比研究,并与特高压直流线路单独架设的过电压水平进行了比较分析;对同塔架设双回特高压直流线路过电压水平的影响因素进行了敏感度分析。研究表明,同塔架设导线布置方式不会引起线路过电压沿线分布特性变化,同时确定了线路过电压水平最高的同塔双回导线排列方式及其过电压水平。

Adopting the way of erecting double circuit UHVDC transmission lines on the same tower,the difficulty of selecting the site for transmission corridor during the development of UHVDC power transmission projects can be alleviated to a great extent.The detailed simulation study of the overvoltage distribution along the double circuit UHVDC transmission lines on the same tower and the highest overvoltage levels are performed;the comparative study on overvoltage distribution characteristics along the double circuit UHVDC transmission lines on the same tower under four different arrangement schemes of conductors and the highest overvoltage levels are carried out and compared with the overvoltage level of UHVDC transmission line singly erected on the tower;the sensitivity analysis on factors impacting the overvoltage levels of the double circuit UHVDC transmission lines on the same tower is conducted.Study results show that the arrangement schemes of conductors do not lead to the variation of overvoltage distribution characteristics along the transmission lines,and the conductor arrangement leading to the highest overvoltage level under double circuit UHVDC transmission lines on the same tower and corresponding overvoltage level are determined.