Aeolian vibration‐based structural health monitoring system for transmission line conductors

Abstract

Summary The transmission line in a power network is similar to a blood vessel. Any disconnection ultimately affects the transmission of electrical energy, and broken strands and detachment of the fittings are early signs of disconnection. Because aeolian vibration occurs on almost all conductors, an aeolian vibration‐based structural health‐monitoring technology for transmission lines is proposed. First, the influence of strand breakage and detachment of the fittings on the natural frequency of the conductor is described, and the influence of temperature changes on the natural frequency is discussed from the two aspects of the temperature‐dependent elastic modulus and temperature‐dependent winding angle. Second, we conducted a vibration experiment and found the law of natural frequency variation caused by broken strands, detachment of the fittings, and temperature changes. Finally, we conducted a field test to measure the conductor vibration on a 110‐kV transmission line. The results show that the natural frequency can be calculated multiple times by the stochastic subspace identification method, and the calculation results are consistent. After a period of measurement, the natural frequency variation is analyzed. Further, how to determine the structural health of the conductor from the natural frequency measured by the technique under actual operating conditions is explained.

Dispersion Reduction of the Source Data Created by Time History Analyses for Developing More Reliable Fragility Curves of Selected Electric Substations Equipment

“…One is the age or the passed time of the operation lifetime of the equipment which may make it more vulnerable against earthquake. For example, the fatigue conditions resulted from Aeolian vibrations in the conductors of power transmission lines, (Zhao et al 2020), can create near-failure conditions in the conductor just before the earthquake. Another reason is believed to be the factors that can have either increasing or decreasing effect on the seismic response of the electric equipment, such as the coupling effect with the adjacent equipment (Yang 2021).…”

Collapse Analysis of a Transmission Tower-Line System Induced by Ice Shedding

“…Ultimately, ninety percent of all transmission tower collapses are caused by longitudinal unbalanced tension caused by uneven icing and uneven ice shedding [4]. With the development of the study on structural vibration control and structural healthy monitoring, these two methods are used to improve the safety operation of the transmission line [5][6][7][8][9]. To determine the key parameters for monitoring and controlling, the failure mechanism of the transmission line caused by ice-shedding should be studied.…”

A structural health monitoring system of the overhead transmission line conductor

“…Although these methods can monitor the motion status and environmental status, they cannot reflect the structural state of the transmission line conductor. The online monitoring technology of aeolian vibration is the most widely used method [6]. This technology estimates the fatigue life of the conductor using the data of bending amplitude monitoring, but it cannot achieve an accurate calculation [7].…”