基于场路结合法的输电线路附近工频磁场计算

Calculation of Power Frequency Magnetic Field Around Transmission Lines Based on Field Circuit Combination Method

目前架空输电线路周围的工频磁场计算主要采用模拟电流法。该法虽然简便易行,但它没有考虑地线或者屏蔽线对工频磁场的影响。本文基于电路理论和电磁场理论提出了场路结合法,可有效解决地线或者屏蔽线对输电线路周围磁场的影响。最后应用此方法对输电线路周围磁场分布的影响参数进行了仿真分析。这些参数包括:输电线路有无避雷线、相导线分裂根数、子导线分裂间距、导线布置形式及同塔双回路相序排列方式等。

Presently the current simulation method is fre- quently used to calculate the power frequency magnetic field around the overhead transmission lines. Although the method is efficient, the main drawback of the method is that it doesn＇t in- elude the influence of earth wire or shielded wire on the magnet- ic field. In this paper we propose a new method named the field circuit combination method which couples the circuit theory with the electromagnetic theory. It is shown that it is effective to include the effect of the earth wire or shielded wire on the mag- netic field. In the end different parameters are studied to derive the key factors of power frequency electromagnetic field. The parameters include： the effect of neutral wires, bundle conductor number of each phase, sub-wires space, the cross-sectional con- figuration of the transmission lines, phase sequence arrangement et al.