【摘要】 利用小波变换的多分辨特性,对轨道不平顺局部检测数据进行一维小波变换多尺度分解,然后对各尺度下重构信号进行幅值谱分析,以发现在轨道不平顺中存在的特征不利波长;同时,基于小波分解后的各层重构信号能有效放大不平顺特征和缩小频段范围,利用Wigner-Ville分布对信号能量的时频聚集性,对各层重构信号进行Wigner-Ville时频分析能很好地提取各波长不平顺大小沿线路里程的分布情况;通过相干分析发现引起车体激扰的不利波长,然后用小波方法提取不利波长所在的特征频段,最后通过互Wigner-Ville分布表征相干不利波长不平顺的时频分布情况。结果表明:结合小波分析理论和Wigner-Ville分布能十分有效地从时频域角度分析轨道不平顺,是一条保证铁路安全运营、提高养护维修质量的良好技术途径。更多还原

【Abstract】 By exploiting the multiresolution characteristic of wavelet transform,we can put the local testing data into multiscale decomposition through 1D wavelet transform,and then analyse the reconstructing signal of each scale using the amplitude spectrum to find the feature unfavorable wavelength existed in the track irregularity;At the same time,we can reduce the cross distraction of the Wigner-Ville distribution based on the fact that the wavelet decomposition can effectively magnify the characteristic of the irregularity and narrow the frequency band,through using the Wigner-Ville distribution which can draw the time-frequency clustering of the signal energy;Finding the unfavorable wavelength that causes the car-body vibration,then extracting the feature frequency band of the unfavorable wavelength,at last,we can finally represent the time-frequency distribution condition of cross unfavorable wavelength through the method of cross Wigner-Ville distribution.The result shows that we can effectively analyse the track irregularity from the time-frequecy domain through combining wavelet method and Wigneer-Ville distribution.It’s a new technical method for guaranteeing the safe running of railway and improving the maintenance quality.更多还原