Computational analysis on unbalanced tension in overhead power lines under non-uniform accreted ice

Abstract

Unbalanced tension in the overhead power lines under non-uniform ice is important for the design of towers. Based on the constant conductor length and numerical iteration methods, a numerical calculation method to determine the unbalanced tension under non-uniform accreted ice in one span for both the single-span and multi-span sections has been developed. Meanwhile, the horizontal tension and sag distribution calculated by the numerical calculation method are in good agreement with the finite element analysis (FEA) model established in the ANSYS software and the field situation. The responses of the unbalance tension and the maximum relative displacement of the conductor under different parameters, including span length, ice length, ice thickness, number of spans, and elevation difference were investigated. Also, the application of a numerical calculation method to practical line situations was discussed. The results show that the non-uniform ice clearance reaches the flashover condition first compared with the static clearance and the dynamic clearance under different span lengths, ice thicknesses, and voltage levels, especially in the low voltage level power lines.