Experiments and numerical simulation on the broken conductors in transmission lines

A three continuous span transmission line section is established.For different types of conductors and ice thickness,conductors breaking experiments are carried out.Under different broken cases,time histories of the tensions and displacements at the middle of conductor spans are measured.The damping coefficients of the line section for different breaking cases are calculated.The dynamic impact factors of the conductor tensions are determined.The experimental results show that the impact effect is more significant for the location nearer to the breaking point.The dynamic impact factors decrease with the increasing of the ice thickness,and the impact factors of conductors without accreted ice are much higher than those of conductors with accreted ice.With the increasing of the ice thickness,the initial tensions before breaking as well as the ratios of the residual static tensions to the initial tensions increase.Nearly all the first peak tensions are close to the initial tensions for the breaking cases with accreted ice.The damping coefficients by the experimental identification are applied to the FEA model.The numerical simulations are performed for different breaking cases.Both the residual static tensions and the first peak tensions by the numerical simulations are well agreed with the experimental values.The maximum differences are 5.6 percentages and 12.9 percentages respectively.