Abstract:The calculation formulas for natural frequencies of continuous spans conductors based on the vibration theory were proposed, and the mode shapes based on the sub-structure approach were obtained.The natural frequencies and mode shapes calculated by the formulas under different span numbers and tension forces were in good agreement with the results of the finite element method, and thus the reliability of the theoretical formulas was verified.The influence of geometric parameters of continuous spans conductors on the dimensionless frequencies was revealed.The conditions for the resonance between different modes of continuous spans conductors were investigated and it is shown that the multi-mode coupling conditions were obviously different from those of single span ones.The motion equations of continuous spans conductors were discretized by using Galerkin procedure, then the non-linear ordinary-differential equations for the multi-mode coupled vibration were obtained.These results establish the base for the study of bifurcation behaviors in the strong internal resonance of continuous spans conductors.
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