基于振动加速度模态分解与重构的轨道局部不平顺分析方法  

Analyzing Method for Local Track Irregularity Based on Mode Decomposition and Reconstruction of Vibration Acceleration

作　　者：曾俊玮 任利惠 季元进 ZENG Junwei;REN Lihui;JI Yuanjin(Institute of Rail Transit,Tongji University,Shanghai 201804,China)

机构地区：[1]同济大学铁道与城市轨道交通研究院,上海201804

出　　处：《铁道机车车辆》2024年第3期11-21,共11页Railway Locomotive & Car

基　　金：博士后创新人才支持计划(BX20200240);中国博士后科学基金(2020M671207)。

摘　　要：低地板轻轨列车的异常振动信号多为非平稳非线性信号,针对传统时频分析方法在非平稳非线性信号处理上的局限,提出将Hilbert-Huang变换(HHT)应用于低地板轻轨列车的异常振动分析研究。针对经典HHT采用的EMD方法存在的模态混叠等困境,提出了先利用完全自适应噪声集合经验模态分解(CEEMDAN)对振动数据进行分解,再通过相关系数法剔除趋势项分量,利用小波阈值法对高频含噪分量去噪,对去噪后的高频分量和低频信息分量进行加权重构,最后进行Hilbert-Huang变换的优化处理流程。以某型低地板轻轨列车为研究对象,通过HHT得到轴箱垂向加速度的Hilbert谱,获取时间—瞬时频率—瞬时能量对应关系并实现冲击点定位,结合边际谱分析振动特征计算质量指数,判断低地板轻轨列车的异常振动原因及故障模式,结果表明该方法对低地板轻轨列车振动的特征提取与振动冲击分析有效可行。The abnormal vibration signals of tramcars are mostly non-stationary nonlinear signals.Aiming at the limitations of traditional time-frequency analysis methods such as Fourier transform in non-stationary nonlinear signal processing,the Hilbert-Huang transform(HHT)is applied to the abnormal vibration analysis of tramcars.In order to solve the mode mixing problems existing in the EMD method adopted by classical HHT,the original vibration data were decomposed by fully adaptive noise set empirical mode decomposition(CEEMDAN),then the trend component was removed by correlation coefficient method,and the high frequency noisy component was denoised by wavelet threshold method.The high frequency and low frequency information components after denoising were weighted and reconstructed,and finally the optimization process of Hilbert-Huang transform was carried out.Taking a certain tramcar as the research object,Hilbert spectrum of vertical acceleration of axle box was obtained by HHT,corresponding relation of time-instantaneous frequency-instantaneous energy was obtained,and impact point was located.Combined with marginal spectrum analysis of vibration characteristics,mass index was calculated,and abnormal vibration causes and fault modes of tramcar were determined.The results show that this method is effective and feasible for feature extraction and vibration and impact analysis of tram vibration.

关 键 词：轴箱加速度 轨道不平顺 振动冲击 经验模态分解 希尔伯特黄变换 边际谱 

分 类 号：U239.5[交通运输工程—道路与铁道工程]