非平稳循环特征极坐标增强及其在发动机故障诊断中的应用  

Polar coordinate enhancement of non-stationary circling characteristic for engine fault diagnosis

作　　者：贾继德[1] 张玲玲[1] 梅检民[1] 肖云魁[1] 

机构地区：[1]军事交通学院汽车工程系,天津300161

出　　处：《振动工程学报》2013年第6期960-964,共5页Journal of Vibration Engineering

基　　金：总后勤部重点项目(AS407C001)

摘　　要：发动机早期磨损故障特征微弱且呈现非平稳循环特征,提出一种非平稳循环特征极坐标增强方法。利用连续小波变换对发动机振动信号进行处理,然后根据发动机工作过程与配气相位的关系对于每一工作循环数据进行等角度采样,将信号特征由直角坐标系映射到极坐标系并进行同步增强,并利用模糊C均值聚类对故障特征参数进行分类识别。仿真信号的分析对比显示了该方法能够削弱噪声干扰,突出信号特征。运用此方法对某型发动机曲轴轴承磨损信号进行分析,有效地提取了曲轴轴承磨损特征信息,准确识别了曲轴轴承不同磨损故障。The early inchoate wear of engine manifests non-stationary circulation characteristic, yet very week. Hence, a polar coordinate enhancement method of non-stationary cycling characteristic is proposed. The continuous wavelet transform method is applied to achieve the time-frequency representation of the vibration signals of engine. Then the data of each working cycle are resampled according to the relationship of the working process and the gas-phase. Afterwards, the signal characteristics in the rectangular coordinate are transformed into the polar coordinate and are synchronously enhanced. Finally, the characteristic parameters are classified by the fuzzy C-means clustering algorithm. Simulated signals are used to test the effectiveness of the proposed method, showing that it can indeed weaken the noise disturbance and strengthen the signal characteristics. The meth- od is also applied to diagnose the wear of the main bearing for a certain type of engine, and the results show that the fault char- acteristics of the bearing are effectively extracted and accurately identified.

关 键 词：发动机 故障诊断 曲轴轴承磨损 特征增强 

分 类 号：TK421.24[动力工程及工程热物理—动力机械及工程]