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When power transmission cables are subjected to oscillatory displacements, due to the wind vibration, fretting fatigue phenomenon takes place, being the main prompter of catastrophic failure. In this work, we investigate the behavior of an 1350-H19 aluminum wire, that is a structural element of the IBIS (ACSR 397.5 MCM) conductor cable, when subjected to fretting fatigue. For this, a numerical methodology was developed, in which a three-dimensional finite element model was constructed to obtain the maximum Von Mises stresses in the vicinity of the wire-to-wire contact. Thus, a stress-based uniaxial fatigue approach was implemented, resulting in S-N curves. The effect of mean stresses on fatigue behavior was also considered through a series of well-known models. The data generated in this process were validated with experimentally obtained S-N curves on a MTS 322.21 machine, especially modified for this purpose. Most of the results were within the limits considered, with slightly conservative tendencies. A new value of adjustable material parameter has been proposed to be used with Walker's model, increasing the accuracy of the predictions.

It is carried out a study regarding the catenaries of the lines of a three-phase transmission system with its neutral conductor grounded at two points. It is investigated the effect of electromagnetic field impinging on such transmission lines (due to lightning currents) by performing the calculation of induced voltages on the conductors. The numerical solution of Maxwell's equations is obtained by using the non-orthogonal finite-difference time-domain method.