考虑弧垂的交流特高压输电线三维电磁场

The 3D electromagnetic field of AC EHV transmission lines with sag

针对1 000 kV特高压交流输电线路的三维电磁计算问题,用有限元分析方法,建立1 000 kV特高压交流线路的计算模型,分别按简化的直导线模型和具有弧垂的实际线路模型,进行线路的三维电磁计算。在相同的对地高度下,直导线和弧垂线下方的横向面电场分布趋势一致;在相同的对地高度下,直导线纵向电场相同,而弧垂线的纵向电场强度在最大弧垂处的数值最大,同时沿着纵向逐渐减弱,计算值与实测值接近。磁场的计算结果与电场有相似的规律。此种的弧垂线路三维电磁场建模方法,能准确地计算出输电线路的真实电磁强度数值。考虑线路弧垂的三维模型计算方法对于特高压输电线路电磁的研究有一定借鉴意义。

To solve the problem of calculating the 1 000 kV AC extra-high voltage transmission line 3-D e- lectromagnetic problem, based on the finite element analysis method, the calculation model of 1 000 kV AC extra-high voltage transmision line is proposed. According to the simplified straight conductor model and the actual line model with sag, calculations of 3-D electromagnetic field of transmision line were made respectively. The calculation results show that the transverse distribution trends of electric field are consistent under the straight line model and the wire with sag on the same height. On the same height, the electric field straights are consistent along the longitudinal of line. The maximum value of the longitu- dinal electric field strength of sag line is in the lowest sag part. At the same time the value of electric field strength decreases gradually along the longitudinal of the sag line. The calculated result and the measured value are close. The results of magnetic field strength and electric field strength have similar rules. The accurate results of electromagnetic strength of transmission line can be obtained by 3-D elec- tromagnetic field modeling. The calculation method of the 3-D electromagnetic field model considering sag has a certain reference value for the electromagnetic research of EHV transmission line.