PERTURBATION-BASED FINITE ELEMENT ANALYSES OF TRANSMISSION LINE GALLOPING

Efficient perturbation schemes are developed to compute the large amplitude, low frequency, galloping vibrations of a multi-span, overhead transmission line. Systematic procedures are formulated to assess the stability of a conductor's wind and ice loaded static profile by employing a multiple-degree-of-freedom finite element model. The use of the computationally most demanding part of the finite element analysis, namely a time marching process, is minimized by employing the averaging methods of Krylov-Bogoliubov and Galerkin. The methods are applied successfully to simulate field galloping records and their usefulness and advantages are demonstrated through illustrative examples. Alternative designs of transmission line clearances and span lengths can be assessed readily, with the help of the procedures, to achieve a cost-effective solution.