Facts and trends in the endurance capability of overhead line conductors, the Cigrė approach

High voltage overhead transmission lines are the backbone of today’s electrical
networks. Their conductors are expected to have a lifetime of more than 50 years.
Unfortunately these conductors are also prone to wind-induced (aeolian) vibrations,
which, if not properly damped, cause fretting fatigue, which again may lead to
conductor damage and sometimes to catastrophic failures. The purpose of this paper
is to present today’s state of the art in this field. The following topics will be covered:
Fretting behaviour of stranded conductors, laboratory determination of fatigue
endurance capability, inner conductor mechanics, assessment of vibration severity
on actual lines and evaluation of conductor residual life. This paper has been
prepared by the Cigré Working Group 11 (Mechanical behaviour of conductors and
fittings – Task Force 7)*

Author: K.O. Papiliou