±800kV滇西北至广东特高压工程极导线与接地极线共塔电磁环境研究

Research on the Electromagnetic Environment of Polar Wires and Ground Electrode Wires on the Same Tower of ± 800 kV Dianxibei to Guangdong UHVDC Project

直流输电线路经过高度城市化的地区时,将直流线路和接地极线路共塔架设是解决输电线路走廊紧缺问题的最佳选择,但目前国内外对于这种塔型的电磁环境鲜有研究。本文对传统电磁环境计算方法进行了拓展,以便能够考虑接地极线对极导线电磁环境的屏蔽作用。以±800 kV滇西北至广东特高压工程为例,分析了水平排列和垂直排列两种共塔架设方式下线路可听噪声、无线电干扰、地面电场和地面离子流密度等的分布特点。结果表明,共塔架设线路的地面电场优于独立架设直流线路,采用极导线垂直排列(上层负极导线)的布置型式可将输电线路走廊压缩约44%。

In highly urbanized areas,erecting ± 800 kV polar wires and ground electrode wires on the same tower is the best choice to solve the shortage of transmission line corridors and scarcity of land resources. However,there are fewresearches on the electromagnetic environment of this type of tower at home and abroad. In this paper,the conventional calculation method is expanded to consider the shielding effect of ground electrode wires to the electromagnetic environment of polar wires. Taking the ± 800 kV Dianxibei to Guangdong UHVDC Project as example,the audible noise,radio interference,total field strength above ground and ion current density under horizontally and vertically arranged modes of same tower hybrid transmission lines are discussed. The results showthat the total electric field strength above ground of same tower hybrid transmissin lines is less than the DC line,and the transmission line corridors can be compressed about 44% by using the vertical arrangement of same tower hybrid transmissin lines.