大跨越输电塔线体系断线响应分析

Analysis of Transmission Line Rupture Response for Long⁃span Transmission Tower⁃line System

为研究大跨越输电塔线体系的断线动力冲击问题,利用ANSYS软件建立了输电塔线体系的有限元模型,采用生死单元法模拟导(地)线的突然断裂。用时程分析的方法分析不同工况下绝缘子以及地线夹具的位移及轴力,发现在靠近绝缘子处断线对绝缘子最为不利,远离地线夹具处断线对地线夹具最为不利。通过对塔身主材的轴力进行动力分析,发现随着高度的增大,塔身主材受到的冲击作用逐渐增大。通过获得输电塔线体系的断线张力,并将断线张力结果与设计规范值即静力计算结果进行比较,发现应用动力有限元的计算结果比规范的静力计算方法得到的导线断线张力大3.5%,即考虑断线的动力冲击作用时,按规范设计的结果存在安全隐患,应适当提高裕度。

In order to study the dynamic impact of transmission line rupture for long⁃span transmission tower⁃line system,the finite element model of transmission tower system was established by using ANSYS software,and the birth⁃death element method was used to simulate the sudden rupture of the conductor/ground line.The method of time history analysis was used to analyze the displacement and axial force of insulator and ground clamp under different working conditions.It is found that transmission line ruptured near the insulator is the most disadvantageous to the insulator,while the transmission line ruptured far away from the ground clamp is the most disadvantageous to the ground clamp.Through the dynamic analysis of the axial force of the main material of the tower body,it is found that the impact effect of the main material of the tower body increases gradually with the increase of the height.The disconnection tension of transmission tower line system was obtained and compared with the value calculated by static calculation method in design specification.It is found that the disconnection tension of transmission tower line system calculated by dynamic finite element method is 3.5%higher than that in design specification.That is to say,when considering the dynamic impact of transmission line rupture,there are hidden dangers in the results designed according to design specification,and the margin should be appropriately increased.