Wire displacement of AAAC overhead line conductors at wedge tension clamp

Abstract

Overhead line conductors are tensioned to fulfill sag limitations. Free-span conditions of common conductors are investigated and documented in literature. In this paper, the structural changes of an all aluminum alloy overhead line conductor near a wedge tension clamp are investigated by x-ray tomography, digital image correlation and finite element analysis. The results achieved with these three methods consistently show that the inner layers of the conductor are slipping relative to the outer layers of the conductor. Additionally, not all wires on the same layer are clamped equally. Thus, there is a mechanical transition zone of approximately 300 mm between the tension clamp and the free-span. This mechanical transition zone and the associated structural changes of the conductor are measured and modeled. The tools used in this study can be applied on other conductors and clamps as well.