An Asymptotic Theory for the Free Vibrations of an Iced Two-Conductor Bundled Transmission Line

摘要

A theory is presented for the calculation of the free vibrations of an iced two-conductor bundled transmission line. As a model a system of two shallow elastic catenaries, connected by rigid massless spacers is considered. The effect of ice-coating is taken into account by assuming that the two catenaries have different mass per unit length. The theory includes a dynamic coupling between the vertical and torsional vibrations. This coupling may result in internal resonance of torsional and vertical modes of vibration; the excitation of the latter mode may be associated with the starting mechanism of galloping. In the conclusions some open problems are formulated concerning the asymptotic character of the approximations.