3D Finite Element Analysis of Electromagnetic Fields in Transmission Line Crossing Areas Under Different Operating Conditions

With the increasing density of transmission lines, line crossings and spans have become more common, and the electromagnetic environment of transmission lines has attracted increasing attention. Investigating the electromagnetic field distribution in transmission line crossing regions is therefore of great significance for line layout and preliminary design. In this study, the parameters of transmission lines in crossing regions are first obtained by parsing the GIM (Grid Information Model) file. A three-dimensional electromagnetic field model of a double-circuit transmission line on the same tower is then established using the finite element method, and the accuracy of the proposed approach is validated by comparison with field measurement data. Based on the developed model, the electric and magnetic field distributions of both the double-circuit transmission line and the crossing region are calculated. Furthermore, the effects of different crossing angles, phase sequence combinations, and voltage levels on the electromagnetic field distribution are systematically investigated. By comparing the electromagnetic field characteristics under different phase sequence schemes, an optimized phase sequence configuration for double-circuit transmission lines and crossing regions is proposed. The results provide a theoretical basis and technical reference for electromagnetic environment assessment and design optimization of transmission lines in crossing regions.