Control of vibration of transmission lines

Abstract

The problem of vibration control of overhead line conductors subjected to laminar transverse wind, which induces stationary vibrations by Karman effect, is important due to the consequences on these structures lifetime and service. We consider the conductor (cable) model as the Euler-Bernoulli beam, fulfilling the authors' condition that detaches the conductor model of the beam model with viscous, hysteretic, or dry friction internal-damping hypothesis. The aeolian vibration control of the conductor is based on the energy-balance principle that takes accounts for the wind-energy input, the energy dissipated by the conductor due to hysteretic self-damping properties (or equivalent viscous damping) and, eventually, the energy dissipated by the Stockbridge dampers. The aim of this approach is to mitigate the vibration level of overhead line conductors. The original analytical expression of the free-vibration modes and the resonance-frequencies equation for the cable with clamped extremities have been produced. The analytical expression of the kinetic energy of the cable is compared with the amount of dissipated energy, obtained by experimental means, for the control of vibration of transmission lines. Some applications are presented here.