Comparison of Fatigue Lifetime Estimation of a Conductor Based on a Standard Vibration Device and Other Structural Health Monitoring System Sensors

Abstract

This article presents an experimental work developed in the context of the study of conductors' fatigue due to the turbulent effect of wind on an overhead high-voltage transmission line. The research is centred on the laboratory study of a conductor segment with a 17 m length. The cable model, fitted with typical anchorages adopted in transmission lines, is mounted on a specially designed anchoring system following the normative prescriptions of CIGRE. An extensive monitoring system is installed, including a load cell, several accelerometers, LVDTs and fibre optic sensors to assess the conductor's dynamic properties and the corresponding dynamic response to the wind loads, here simulated by a random excitation applied from a shaker. Based on the conductor response measured with the different sensors, with and without a Stockbridge damper, the fatigue lifetime of the conductor is calculated. A comparison is made of the fatigue lifetime estimated from acceleration, strain or LVDT measurements, the latter simulating the procedure typically used based on the VIBREC measurements. Finally, the Stockbridge damper's dissipation capacity in increasing the conductivity lifetime subject to aeolian vibrations is analysed as a function of the position of the damper.