Numerical Algorithms for Calculating Temperature, Layered Stress, and Critical Current of Overhead Conductors

Abstract

Accurate calculation of temperature, stress, sag, and critical current (corresponding to critical temperature) of operational overhead conductors is important for ensuring the strength and sag safety of overhead lines. Based on 2D steady-state heat transfer equations, this article studies the temperature fields of the cross section of typical electrified conductors and establishes numerical simulation methods for calculating the layered stress, sag, and critical temperature. Using the algorithm, the relationship between the critical temperature and characteristics of conductors (e.g., the sag and tensile force) is studied. The results are verified by a comparison with the test results for heat-resistant aluminum alloy conductors JNRLH1/G1A-400/65 and JNRLH1/G1A-630/55. Finally, the paper studies the relationship between the critical temperature of the conductor and its most sensitive factors.

Calculation Methods of High-Voltage Direct Current (HVDC) Line Sag Considering Meteorology

“…The use of finite element simulation analysis to analyze the temperature distribution of aluminum stranded wire has a good effect, but such studies often overlook the influence of radial thermal expansion [16]. Therefore, some scholars divide the conductor temperature into different layers, that is, by analyzing the temperature of each layer of the conductor and calculating the layer stress, sag, and critical temperature of the conductor, but they ignore the temperature difference caused by convective heat dissipation at different positions on the same layer [17]. In fact, steelcore aluminum-stranded conductors have thermal expansion properties like those of other metals [18].…”