特高压交流输电线路分裂导线表面电场计算分析

Calculation and Analysis on Surface Electric Field Intensity of Bundled Conductors for UHVAC Transmission Lines

为研究特高压交流输电线路分裂导线表面电场强度,笔者基于偶极子法,计算了4种典型塔型特高压交流输电线路分裂导线表面电场强度,进而分析讨论了导线对地平均高度、导线布置方式、分裂间距、相间距、分裂数、子导线截面、相序、架设屏蔽线等因素对分裂导线表面电场强度影响的规律和特点。结果表明:分裂导线各子导线由于空间位置不同使得其表面最大电场也不同;分裂导线分裂数、截面对导线表面最大电场的影响最大,导线对地平均高度、分裂间距、相间距离及布置方式对其表面最大电场强度的影响相对较小;双回线路相序排列方式对上、下相分裂导线表面电场强度影响较大,对中相导线表面电场影响相对较小;架设屏蔽线会增大分裂导线表面电场强度。

According to the actual situation of the UHVAC transmission lines, the surface electric field intensity on the bundled conductors is calculated based on the dipole method. Then, the effects of the factors, such as the average height of lines to ground, layout, bundled distance, distance among phases,number of bundles, cross-section area of a conductor, phase sequence, and shielding lines, on the surface electric field intensity of bundled conductors are analyzed and discussed. The results show that： 1 The surface electric field intensity of the bundled conductors is different; 2 The number of bundles and cross-section area of a conductor impose significant effects on the surface electric field intensity, while other factors, such as the average height of lines to ground, layout, bundled distance, and distance among phases, impose relatively smaller effects on the surface electric field intensity; 3 The phase sequence has significant effect on the surface electric field intensity of the top and bottom phases of transmission lines,and has smaller effect on the middle phase; and 4 The shielding lines can enhance the surface electric field intensity of bundled conductors.