Finite Element Analysis of Dynamic Characteristics of Large Span Transmission Line

The dynamic characteristics of large span transmission line are researched by finite element method (FEM). Based on spatial cable interpolation functions and the strain- displacement relations of spatial cable theory, the finite element model of the transmission line which has 3 DOF node is proposed. The parameter of FEM emulation mode such as aero-vibration force, the conductor self-damping are emphasized by the energy equivalent theory. The damping power of a single-degree of-freedom system is equivalent to modal self-damping., the wind input power is translated into the micro-wind excitation force for unit nodes, and all the units of mass and stiffness matrix are obtained through the principle of virtual work. The motional equation is solved through NEWMARK method. The results of an example show that the dynamic characteristics of the transmission line simulated by the cable element are in good agreement with test results, which verify the correctness of the finite element model of the conductors. The method lays foundation for further research on protecting breeze vibration of transmission lines.