Original real-time observations of aeolian vibrations on power-line conductors

Aeolian vibrations of power lines are induced by Von Karman vortex shedding. Vortex shedding is characterized by vibration frequencies in the approximate range of 3-100 Hz (sometimes higher) and by amplitudes that can reach conductor diameter for the lower range of frequencies, under very slow to medium wind speed (0.5 m/s to about 7 m/s). Conductor vibration causes localized bending, which may cause fatigue failure of the conductor strands. The amplitude of vibration very much depends on conductor self damping, which may be very low. The purpose of this paper to show measurements of these vibrations carried out by a new experimental device (developed by the authors), which is able to perform continuous measurements in the full range of frequencies and amplitudes. A statistical overview of measurements is presented and Lifetime is estimated