摘要
水电站厂房空间结构复杂,同时振动测试信号中常混杂各种噪声,使得水电站厂房结构振源传递路径的分析难度增大;论文将传递熵方法与基于EMD分解的小波熵阈值去噪方法相结合,实现水电站厂房振动传递路径的识别。首先采用EMD分解和小波熵方法自适应地根据信号能量特征确定对应尺度的去噪阈值,对振动测试信号去噪;然后采用传递熵的方法识别厂房结构振源的传递路径。通过模拟信号的分析证明了该方法在判断信号传递方向方面的合理性。将该方法应用到一大型水电站厂房,结合现场实测振动数据对尾水涡带的垂向传递路径进行了识别,并计算了测点之间的信息传递率。结果表明尾水涡带引起的垂向振动主要传递路径为:尾水管→机墩(定子基础、下机架基础)→厂房上部结构楼板。
The hydropower house is a sophisticated spatial structure,and its vibration testing signals are of-ten mixed with various noises, which makes it more difficult to analyze the vibration source transmissionpath. In this paper,a new method was presented,which is combined the adaptive wavelet threshold denois-ing method based on EMD and the transfer entropy method. The method can accurately identify the verticalvibration transmission path of hydropower house. First, in order to denoise the vibration test signal, EMDdecomposition and wavelet entropy method were adopted to adaptively determine the denoising threshold ofthe corresponding scale according to the energy characteristics of the signals. Then, the transfer entropymethod was used to identify the transmission path of structural vibration source. The validity of the methodwas proved by the numerical simulation of the harmonic signals. Based on the field experiments vibrationsignals of a large scale hydropower house structure,the transfer direction and vertical transfer path of vor-tex belt were identified, the rate of information transmission between measuring points was also calculated.The results show that the main vertical vibration transfer path caused by vortex belt is as follows： drafttube → turbine pier（the foundation of stator and the foundation of lower bracket） → superstructure of thepowerhouse（generator floor slab）.
作者
王海军
王宁
练继建
WANG Haijun;WANG Ning;LIAN Jijian(State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300350,China;College ofCivilEngineering,Tianjin University,Tianjin 300350,China)
出处
《水利学报》
EI
CSCD
北大核心
2018年第6期732-740,共9页
Journal of Hydraulic Engineering
基金
国家重点研发计划项目(2016YFC0401902)
天津市重点领域创新团队(2014TDA001)
高等学校学科创建引智计划项目(B14012)
关键词
水电站厂房
经验模态分解
小波熵
传递熵
传递路径
hydropower house
empirical mode decomposition
wavelet entropy
transfer entropy
transfer path
