Optimum design of viscoelastic dynamic neutralizers for overhead transmission lines: distributed excitation model

It is well known that overhead transmission lines are particularly prone to aeolian excitations. Because of those excitations and of their own characteristics, the lines may work in resonance, with high vibration amplitudes, which could lead to fatigue. To increase the life time of those structures, dynamic neutralizers are used. The dynamic neutralizers used nowadays are extremely efficacious at some discrete frequencies, but very disappointing away from those, still within the frequency range of concern. The employment of viscoelastic dynamic neutralizers aims to control the vibrations in a wide frequency band, due to the large damping usually introduced by viscoelastic materials. In this work, a fresh methodology to optimally design a system of viscoelastic dynamic neutralizers is proposed, regarding the excitation as distributed along the line, which simulates the real action of the wind. Results based on numerical simulations over a 30 m long experimental line are presented.