Calculation of Equivalent Resistance for Ground Wires Twined with Armor Rods in Contact Terminals

Abstract

Ground wire breakage accidents can destroy the stable operation of overhead lines. The excessive temperature increase arising from the contact resistance between the ground wire and armor rod in the contact terminal is one of the main reasons causing the breakage of ground wires. Therefore, it is necessary to calculate the equivalent resistance for ground wires twined with armor rods in contact terminals. According to the actual distribution characteristics of the contact points in the contact terminal, a three-dimensional electromagnetic field simulation model of the contact terminal was established. Based on the model, the current distribution in the contact terminal was obtained. Subsequently, the equivalent resistance of a ground wire twined with the armor rod in the contact terminal was calculated. The effects of the factors influencing the equivalent resistance were also discussed. The corresponding verification experiments were conducted on a real ground wire on a contact terminal. The measurement results of the equivalent resistance for the armor rod segment showed good agreement with the electromagnetic modeling results.

Investigation of sag behaviour for aluminium conductor steel reinforced considering tensile stress distribution

“…The FEA model of ACSR is verified by the temperature rise experiments of a 15 m new conductor [ 23 ]. The conductor is formed into a closed loop by a parallel groove clamp, and part of it (length of 1.5 m) is set in a closed wind tunnel, as shown in figure 7 a .…”

Resilience Assessment and Its Enhancement in Tackling Adverse Impact of Ice Disasters for Power Transmission Systems

“…To support the ice loads and predict ice cover thickness, physical methods [12], empirical methods [13,14], and intelligent methods [15] were introduced. The stable operation of overhead lines affected by ground wire breakage accidents was discussed in [16]. A technique for modelling ice storms was developed in [17], which was also applied to evaluate the impact of ice storms on the Swedish transmission network.…”

A New Method for Determining the Connection Resistance of the Compression Connector in Cable Joint

“…A number of methods have been employed to calculate the contact resistance in the literature including finite element analysis (FEA), experimental measurement, and electrical contacts model analysis (ECMA) [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. In the FEA method, some researchers have added an extremely thin film on the contact interface of the two connectors.…”

“…The actual contact condition was then simulated by changing the material properties of the film [8,9]. Other researchers have adopted a number of tiny conductive bridges on the contact interface to simulate the contact condition [10][11][12]. The electric-thermal coupling model of the cable joint was also established for assessing its hot spot and ampacity [13,14].…”

“…However, in the above methods, the stranded conductor was simplified as a single cylinder to save computing resources and pursue convergence [11,[13][14][15]. To attain an accurate calculation of connection resistance, it is necessary to fully consider the stranded and compressed structure of the cable conductor, the local plastic deformation of the ferrule, and the actual contact interface between the ferrule and the cable conductor.…”