Nonlinear Dynamic Analysis of Galloping of Iced Bundle Conductor Based on Curved Beam Theory

Based on the strain-displacement relationship of the spatial curved beam theory，a hybrid model for galloping analysis of iced bundle conductors with three translational degrees of freedom and one rotational degree of freedom is established. Considering the aerodynamic force nonlinearity and the geometric nonlinearity of the large amplitude motion for the iced conductor，the nonlinear dynamic equation of the iced bundle conductors is established with the virtual work principle. The equation is transformed into the sub-space according to the mode superposition method and solved by the time integration algorithm. Then，the element independence is verified by numerical calculation，and the influence of the number of elements on the first six frequencies of iced conductors is analyzed. Furthermore，the modal convergence is studied，and the effect of modal truncation on galloping response is analyzed. Finally，the influence of aerodynamic force on structural frequency is analyzed. The results show that the aerodynamic force has a significant effect on the torsional frequency of the bundle conductor，which accurately reflects the dynamic characteristics of the transmission line. On the other hand，the hybrid model of iced bundle conductors has reliable accuracy in calculating the galloping analysis of transmission lines，indicating that the hybrid model can predict the actual galloping response of transmission lines and facilitate the implementation of subsequent control design. © 2024 Hunan University. All rights reserved.