特高压直流输电线路电磁环境及对地距离探讨

Electromagnetic Environment and Line-to-ground Distance for UHV DC Transmission Lines

±800kV上海庙—山东及±800kV锡盟—江苏特高压直流线路工程采用8×1 250 mm2导线,这在特高压直流线路工程中尚属首次。通过计算±800kV直流线路在不同分裂根数和导线截面下的无线电干扰、可听噪声、地面合成及标称电场强度、离子流密度等电磁环境效应,并对比分析电磁环境效应随导线截面及分裂数的变化规律;依据电磁环境限值要求和计算结果,结合以往工程由电磁环境决定的导线对地距离取值,推荐±800kV特高压直流线路在采用8×1 250 mm2导线下的对地距离取值,为工程设计提供依据。

The line conductor which has 8 sub-conductors with the cross-section of 1 250 mm2 is first applied in ±800 kV UHV DC Transmission Lines of the Shanghaimiao-Shandong and Ximeng-Jiangsu UHV DC projects. The radio interference, noise, electric field and ion current produced by the transmission line are calculated, and their change rules are analyzed. According to requirement of the electromagnetic environment limit and the calculated result and considering line-to-ground distance decided by electromagnetic environment in the past project, the line-to-ground distance of ±800 kV UHV DC transmission line, which adopted 8xl 250 mm2 conductor, is recommended.