基于NExT的转角输电塔自振频率实测研究  

Identification on Natural Frequencies of Transmission Angle-tower Based on NExT Through Field Measurement

作　　者：吴毅江 王干军 陈波[2] 郭栩文 王年孝 

机构地区：[1]广东电网公司中山供电局,中山528400 [2]武汉理工大学道路桥梁与结构工程湖北省重点实验室,武汉430070

出　　处：《武汉理工大学学报》2014年第7期102-107,共6页Journal of Wuhan University of Technology

基　　金：国家自然科学基金(51178366);南方电网公司科技项目(K-GD2013-0222);霍英东基金(131072);中央高校基本科研业务费专项资金资助项目(2013-II-015)

摘　　要：基于自然激励技术和特征系统实现算法,通过现场实测研究了某220kV大跨度转角输电塔线体系的自振频率。基于有限元理论建立了一塔两线的输电塔线体系分析模型,并考察了有无导线时输电杆塔的动力特性的差异。基于理论分析的输电杆塔振型特点,并结合实际杆塔的构造特点,制定了测试方案和传感器布置位置。通过现场实测获得了结构的加速度响应。基于NExT技术得到了加速度的脉冲响应信号,并在此基础上采用特征系统实现算法进行了各工况下结构体系的自振频率的识别。结果表明,实测结果与理论结果较为吻合。由于导线的存在,结构体系的自振频率发生了一定程度的减小,输电杆塔表现出了较为明显的扭转振动特点。The natural frequencies of a 220 kV large scale transmission angle-tower were identified based on NExT（Natural Excitation Technique）and ERA（Eigensystem Realization Algorithm）through field measurement.The finite element model of the coupled tower-line system with one tower and two lines were constructed to investigate the variations of structural dynamic properties with/without transmission lines.The testing plan and sensor installation scheme were determined based on the properties of mode shapes and the tower configuration.The structural acceleration responses were collected through field measurement.Furthermore,impulse response functions of acceleration responses were computed by using NExT to identify the natural frequencies of the transmission tower with the aid of the ERA.The results indicate that the identified natural frequencies agree well with those from the finite element analysis.The natural frequencies of the tower decrease to some extent due to the effects of the transmission lines and obvious torsional effects can be observed.

关 键 词：输电转角塔 自振频率 自然激励技术 现场实测 

分 类 号：O346.5[理学—固体力学]