Calculation of AC resistance for Contact Terminal Between the Ground Wire and Armor Rod Based on Axial Thermal Circuit Model

It is of great significance to acquire the AC resistance of ground wire and armor rod contact surface accurately when analyzing the breakage mechanism of the contact surface of ground wire. This paper presents a method for calculating the AC resistance of ground wire and armor rod contact surface based on axial thermal circuit. The thermal parameters in the axial thermal circuit model are determined by genetic algorithm. Moreover, the effects of different loading current and the time calculation step on the calculation results are analyzed. The study results show that the proposed method can effectively calculate the AC resistance of the contact surface at different temperatures. And the resistance at the steady state temperature decreases with the increase of loading current. The time calculation step has little effect on the calculation results.