Predicting distribution of aeolian vibration amplitude of undamped overhead transmission lines
Shaoqi Yang, Luc Chouinard, Sébastien Langlois, Pierre Van Dyke, Josée Paradis
Abstract
The most widely accepted estimation procedure of the severity of aeolian vibration is by calculating the maximum oscillation amplitudes of the conductor using Energy Balance Principle (EBP). However, the EBP is based on wind tunnel results where only one frequency is excited, while observations and experimental results show that multiple resonant modes are excited simultaneously. Furthermore, the required number of cycles of each amplitude level is not provided by current EBP-based methods. In this paper, vibration data from an experimental undamped ACSR Bersfort test line in Quebec, Canada, is recorded and analyzed. For each record of aeolian vibrations, amplitudes are fitted to a Rayleigh distribution based on the narrow-band assumption. The number of cycles and Rayleigh parameter are then related to wind conditions through a modified Strouhal frequency and EBP methodology. A statistical model is proposed to relate vibration profiles and wind input while considering wind turbulence intensity. The proposed method performs well and gives accurate estimates of both vibration amplitudes and number of cycles for ACSR Bersfort conductor. Physical and statistical theory is provided for each step of the method in order to extend the application of the method to other types of conductors or different line configurations. • Predicting the number of cycles for each amplitude level during aeolian vibration. • Modified Energy Balance Principle to accommodate turbulent wind conditions. • A statistical model linking detailed vibration profiles to maximum amplitude. • Validation through measurements from a test line featuring ACSR Bersfort conductor. • Detailed steps for broadening application to other ACSR line configurations.