±1100kV特高压长悬臂输电铁塔风振特性研究

WIND-INDUCED DYNAMIC RESPONSE AND VIBRATION COEFFICIENT OF ±1100 KILOVOLT DC UHV TRANSMISSION TOWER WITH LONG CANTILEVER

1100 kV长悬臂输电塔结构第一振型为扭转振型,结构的力学特征与传统输电铁塔有较大差异,其风致响应和风振系数具有研究意义。在论证DL/T 5154—2012《架空输电线路杆塔结构设计技术规定》忽略结构物外形、质量沿高度突变的影响,未能准确反映整塔风振系数的基础上,基于MATLAB采用线性滤波法中的自回归法对大气边界层的脉动风速进行了模拟,利用ABAQUS软件对该输电塔进行动力时程分析。根据结构的动力响应,计算输电塔结构塔身和横担部分的风振系数,并进行安全性验证。经分析可知:风振系数沿高度呈线性分布,但在横担附近存在较大突变,且沿长悬臂方向变化幅度不大。

The first vibration mode of the±1 100 kV DC UHV transmission tower is torsion,and the structural mechanical properties of the tower are different from that of the ordinary transmission tower,so it is worth to study the wind-induced dynamic response and vibration coefficient of the tower.In Technical Code for the Design of Tower and Pole Structures of Overhead Transmission Line(DL/T 5154—2012),the normative value failed to accurately reflect the wind-induced vibration coeffcient of the whole tower,due to ignoring of the influence of structure shape and the mutation of quality along the height.On this basis,the auto-regression method in linear filtering method was used to simulate the fluctuating wind velocity of the atmospheric boundary layer,and the time-history analysis was conducted by using ABAQUS.The wind-induced vibration coefficients of the tower body and cross arm were calculated using the data above.The results showed that wind-induced vibration coefficients were linearly distributed along the height,but there was a large mutation near the cross arm,and the variation in the direction of the long cantilever was not large.