School of Electronics and Information, Xi'an Polytechnic University, Xi'an 710048, China.
School of Electro-Mechanical Engineering, Xidian University, Xi'an 710070, China.
Sensors (Basel). 2018 Dec 10;18(12):4355. doi: 10.3390/s18124355.
In view of the settlement problem of transmission tower foundation, the vibration characteristics of transmission towers under wind force are measured experimentally. In this paper, the 110 kV cat head transmission tower of Xi'an Polytechnic University is measured and analyzed. Firstly, the acceleration sensor and meteorological sensor are installed on the tower to collect the vibration response and environment parameters of the tower in real time. Then, an experiment platform is built to simulate the tower settlement, and the vibration response of the tower after settlement is measured in time. Finally, the low-order modal frequencies of the transmission tower before and after settlement under wind force load are extracted by stochastic subspace identification (SSI), and the relationship between modal frequencies of different modes is analyzed via temperature correction. By comparison and analysis, it is obvious that the X-direction modal frequencies before and after settlement under natural wind load are changed, and the change rate increases with the increase of settlement displacement, which can be used as effective evidence for judging the settlement of transmission tower foundation.
针对输电塔基础的沉降问题，对风力作用下输电塔的振动特性进行了实验测量。本文以西安理工大学的 110kV 猫头型输电塔为研究对象，进行了测量与分析。首先，在塔上安装加速度传感器和气象传感器，实时采集塔的振动响应和环境参数。然后，搭建实验平台模拟塔体沉降，及时测量沉降后塔的振动响应。最后，通过随机子空间辨识（SSI）方法提取了输电塔在风力荷载作用下沉降前后的低阶模态频率，并通过温度修正分析了不同模态之间的模态频率关系。通过对比分析，明显看出了自然风荷载作用下输电塔在沉降前后的 X 向模态频率发生了变化，且变化率随着沉降位移的增加而增大，可作为判断输电塔基础沉降的有效依据。
