交流同塔双回特高压输电线路无线电干扰研究

Study on Radio Interference of AC UHV Double Circuit Transmission Lines on the Same Tower

电磁环境问题是建设特高压输电的关键技术问题,导线电晕产生的无线电干扰将直接影响着线路导线的选取和排列方式及导线对地高度和塔型的确定,为此计算分析了交流同塔双回特高压输电线路无线电干扰,得出如下结论:1000kV同塔双回线路采用2种塔型时,8×LGJ-630及以上截面导线线路的无线电干扰完全满足好天气55dB的要求;若要满足58dB的限值,导线逆相序排列时需大范围提高导线对地高度;导线同相序排列对控制无线电干扰有利,但会大大提高地面电场强度;从控制无线电干扰角度出发,塔型1优于塔型2。

AC UHV power transmission has become the strategy and program of building strong electric power grids in our country for it can transmit high voltage and long way and realize electric resource optimizing collocation in a wide range. Compared with single-line, same tower double-line has the advantage of reducing the line corridor and saving the land resource, optimizes the arrange way of conductor at the same time, and reduces electric and magnetic field on the ground, so it could become a important way of developing AC UHV power transmission in our country. The problem of electro-magnetic environment is the key technique problem in building UHV power transmission. Radio interference as the characteristic of conductor corona will directly influence the choice and arrange way of the line conductor and the settlement of the height the conductor to the earth and the tower type. This study carried out the calculation and analysis on the radio interference of AC same tower double UHV power transmission and proposed the line parameter satisfied with the request of radio interference. We can draw the conclusion as follows： 1） 1000kV double circuit on one tower, the two kind of tower, the cross-section is larger than 8×LGJ-630, mentioned above. The value of radio interference below 55dB（μV/m）. To satisfy the limit of 58dBμV/m, the height of conductor should be increase in a large range when it is arranged in inverse array of phase. 21 The same array of phase can reduce the value of radio interference, but will increase the electric intensity on the ground. As a result, when we choose the array of the conductor, we should consider the two factors. 3） The tower 1 is recommended as a result of considering of reducing the radio interference.