Transmission line system having improved stability characteristics from wake-induced subspan oscillations

摘要

A transmisson line system having improved stability from wake-induced oscillations in a bundle of subconductors wherein longitudinally spaced transmission line towers support a span of subconductors therebetween, and the subconductors are connected in bundled relation by a plurality of spacer members disposed in longitudinally spaced relation along the length of the bundle defining adjacent subspans of distinctly different, predetermined length therebetween. More specifically, the spacer members define a minimum length subspan having a length determined on the basis of required torsional rigidity in the bundle, a maximum length subspan having a length determined on the basis of physical and electrical characteristics of the transmisson line to prevent "sticking" between adjacent subconductors and on the basis of atmospheric conditions to reduce the oscillation capabilities of the bundle, and an intermediate length subspan, as required by the overall length of the span, having a maximum difference in length with respect to the maximum length subspan consistent with minimizing the quantity of spacers used in the span. The spacer members are located away from a selected number of the nodes of the rigid body modes of the wake-induced oscillations of the subconductors which can possibly be excited by wind of a given velocity so as to dampen the oscillations and prevent damage to the system.