Calculation of Field Strength of Bundle Conductor Surface of Transmission Lines and Analysis of It along the Transmission Line

With the development of EHV/UHV transmission technology, the calculation of the electric field strength on the surface of bundle conductors is a major problem. In this paper, considering the influence of sag, a calculation model of the field strength of the wire surface based on the CSM is proposed. The model firstly equates the bundle conductors into a single wire, and then uses the conformal transformation and considers the interaction between bundle conductors, finally get the distribution along the maximum surface field strength of the bundle conductors. The accuracy of the calculation method is verified by comparison with COMSOL Multiphysics simulation results. Finally, this model is used to calculate the distribution characteristics of the maximum field strength of the conductor surface in the cross-over region when the 1000kV line crosses the 500kV line.