Response characteristic parameters of six-bundle conductor lines in ultra-heavy ice zones following ice-shedding

For a transmission line passing through ultra-heavy ice zones, the ice on the conductor line may be thicker than 50 mm, and in this case small initial tension in the conductor lines leads to obvious nonlinear vibration following ice-shedding. In this paper, dynamic responses of six-bundle conductor lines in ultra-heavy ice zones are numerically simulated by means of the nonlinear geometric finite element (FE) method, which is verified by reduced-scale modeling test. The jump height, axial unbalanced force and transverse swing of conductor lines following ice-shedding are defined to reflect the characteristics of the dynamic responses. Parameter study on the dynamic responses of isolated-span and multi-span lines with different structural, icing, ice-shedding, and wind parameters following ice-shedding is carried out and a dataset is then created. Using the dataset and the extratrees machine learning algorithm, prediction models for the dynamic response parameters are created and the software is developed. Estimation formulas for the maximum jump height and transverse swing of multi-span lines in ultra-heavy ice zones are proposed. The obtained results provide a foundation for the design of the electric insulation clearance and structure strength of the six-bundle conductor lines in ultra-heavy ice zones.