基于小波包Teager散布熵的轨道车辆路基振动特征提取方法研究

RESEARCH ON VIBRATION FEATURE EXTRACTION METHOD OF RAIL TRANSIT VEHICLE SUBGRADE BASED ON WAVELET PACKET Teager DISPERSION ENTROPY

变压器等电气设备的吊装、转运环节是疏于监控的薄弱环节,极易发生由机械冲击引起的二次损伤。对变压器轨道运输车行进过程中受路基振动引起的冲击响应开展研究。首先,建立了轨道运输车⁃变压器耦合分析模型,利用有限元分析得出轨道运输车⁃变压器耦合分析模型在路基振动作用下的核心响应区域。然后,提出了一种基于小波包散布熵的非周期瞬态响应特征提取方法。该方法通过小波包最优子带树结构对整个频带进行良好的稀疏性分割,将包含多种信息的一维数据分解到不同维度,实现信号的有效分解,通过Teager能量算子(Teager Energy Operator,TEO)增强子带信号的冲击特性,利用散布熵选取包含冲击响应特征的子带信号。最后,通过路基振动仿真信号验证了所提方法能够准确从耦合路径干扰中提取出非周期性瞬态冲击响应成分。

The hoisting and transfer of electrical equipments such as transformers are weak links that are neglected in monitoring,and secondary damage caused by mechanical impact is very easy to occur.The impact response of transformer rail transit vehicle caused by subgrade vibration was studied.Firstly,the rail transit vehicle transformer coupling analysis model was established,and the response area of the rail transit vehicle transformer coupling analysis model under the action of subgrade vibration was obtained by finite element analysis.Then,a non⁃periodic transient response feature extraction method based on wavelet dispersion entropy was proposed.This method performed good sparsity segmentation of the whole frequency band through the optimal subband tree structure of wavelet packet,decomposed the one⁃dimensional data containing a variety of information into different dimensions,and realized the effective decomposition of signals.The impact characteristics of subband signals were enhanced by Teager energy operator(TEO),and the subband signals with impact response characteristics were selected by dispersion entropy.Finally,through the subgrade vibration simulation signal,it is verified that the proposed method can accurately extract the aperiodic transient impact response components from the coupling path interference.