高速列车万向轴不平衡故障检测的形态滤波方法

摘要

Structure element is a significant component in mathematical morphology filter,which directly influence the analysis accuracy.To overcome the defects of the widely used flat structure element and triangular structure element,a Hamming window based structure element is proposed in this paper to improve the morphology filter with an application to the fault detection of high speed train cardan shaft.Firstly,the defects of the flat structure element and triangular structure element are analyzed theoretically from the perspective of the basic constitution of structure element and their frequency response function.Then the advantages of Hamming window are shown by comparison with other common used windows.The Hamming structure element is constructed consequently and applied to morphology filter.A test rig experiment is conducted on the unbalance test bench of cardan shaft.The results show that the morphology filter using a Hamming structure element is effective to identify the fundamental frequency and multiple frequencies caused by the imbalance of the cardan shaft.Compared with the traditional triangular structure element,this method is better to manifest the fault features.%结构元素是数学形态学滤波器的重要组成部分,直接影响滤波的精度.针对目前广泛使用的直线和三角结构元素的缺陷,提出一种基于汉明窗的结构元素,对形态滤波方法进行提升,用于高速列车万向轴不平衡故障检测.首先从结构元素的基本构成形式以及频率响应的角度,在理论上对直线和三角结构元素存在的不足进行了分析.再通过对多种常用的窗函数进行比较,论证汉明窗的优势所在,据此构建汉明结构元素,并将其应用于形态滤波中.在万向轴不平衡试验台进行了试验,结果表明:基于汉明结构元素的形态滤波方法能有效地识别出万向轴不平衡引起的基频和倍频故障特征,与传统的三角结构元素相比,此方法更能彰显故障特征.