Modeling and Loading Effect of Wind on Long-Span Cross-Rope Suspended Overhead Line with Suspension Insulator

Abstract

The long-span Cross-Rope Suspended (CRS) system is composed of a transmission line (conductor), a long-span suspension cable, and an insulator. The previously introduced long-span CRS with a Tension Insulator (CRSTI) has shown applicability in mountainous areas. However, the tension insulator divided the suspension cable into several sections, which made the construction of a long-span CRS rather difficult. This paper introduces long-span CRS with a Suspension Insulator (CRSSI), in which the suspension cable was not disconnected, and the conductor was supported by a suspension insulator connected to the suspension cable. For the purposes of assessment, the initial shape of the suspension cable with concentrated loading from the self-gravity of the suspension insulator and the conductors was studied, and practical lengths in construction could be calculated exactly. Secondly, the structural performance of CRSSI, including its dynamic properties and the loading effect of wind, was discussed by means of numerical analysis. Vibration modes of the structure were obtained by FE analysis. Finally, structural deformation under static wind loading was studied. The result of the analysis showed that the stiffness of CRSSI was lower than CRSTI. The first frequency of CRSSI was 6% smaller than CRSTI. Regarding static wind loading, additional displacement of the insulator contributed to the maximum displacement of long-span CRSSI. Apparently, the displacement of the suspension insulator increased with wind speed. Moreover, the number of spans has an insignificant influence on tension force and deformation.