基于车辆动态响应的车轮多边形自动识别方法

当列车高速运行时,车轮多边形会导致高频轮轨冲击,对车轴、车轮、钢轨等轨道-车辆系统零部件疲劳寿命产生极为不利的影响。本文基于车辆动态响应,利用广义共振解调方法实现了车轮多边形磨耗诊断。首先利用同步压缩短时傅里叶变换得到信号的高分辨率时频谱,然后从时频谱上自动提取时间-能量信息,用于冲击引起的高频振动和低频信号分离;通过Lp范数准则确定带通滤波范围之后,利用广义Hilbert包络解调方法对带通车辆动态响应信号进行解调,提取其中隐含的车轮多边形磨耗信息。分析结果表明,该方法可以有效地诊断车轮多边形磨耗。

Automatic Method for Polygonalization of Wheel Treads Based on Vehicle Dynamic Response

When the train runs at high speed,the polygonalization of wheel treads will produce high-frequency wheelrail impact. This impact may be detrimental to the fatigue life of the vehicle system and the rail system components such as axles,wheels and rails. Based on the vehicle dynamic response,the generalized resonance demodulation method was applied to realize the diagnosis of polygonalization of wheel treads. At first,the high-resolution time-frequency spectrum of the signal was obtained by synchrosquezed short-time Fourier transform. The time-energy information was automatically extracted from the time-frequency spectrum. This information may be used to separate the low-frequency signal and the high-frequency vibration due to impact. The band-pass filtering range was determined by norm criterion. The generalized Hilbert envelope demodulation method was used to demodulate the dynamic response signal of the bandpassed signal,and the polygonalization information of the wheel treads was extracted. The analysis results show that this method can effectively diagnose polygonalization of wheel treads.