变工况机械动态信号瞬时耦合的理解、识别与故障预示

项目名称： 变工况机械动态信号瞬时耦合的理解、识别与故障预示

项目编号： No.51505147

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 李勇

作者单位： 华东理工大学

项目金额： 20万元

中文摘要： 实际机械系统的非线性特征使得表征其运行状态的动态信号具有本质上的非平稳与非线性特性。在变工况条件下，不仅反映设备故障的特征频率会随着工况变化，同时系统的传递函数也是时变的，并使得信号内在非线性耦合关系以及耦合程度瞬时变化，为故障特征提取带来新的挑战。开展变工况动态信号的特征提取和故障预示方法研究不仅具有切实的理论意义和工程应用前景，也是机械故障诊断领域近年来研究的前沿科学问题。在这一背景下，课题从变工况机械动态信号非线性瞬时耦合机制研究入手，结合变工况动态信号的耦合特点，研究适用于非平稳信号非线性瞬时耦合特征识别的自适应瞬时小波双谱方法，并以此为基础，建立基于动态信号非线性瞬时耦合特征的变工况故障预示方法。相关研究工作可为变工况机械设备的状态评估与故障预示提供理论基础，并可望为变工况条件下的齿轮箱、滚动轴承、滚珠丝杠等关键回转部件的故障识别等工程应用提供技术手段。

中文关键词： 非线性瞬时耦合；特征提取；瞬时小波双谱；故障诊断；变工况

英文摘要： Suffering from the nonlinearity of mechanical system, dynamic signals of machinery are non-stationary and nonlinear in nature. In varying operating condition, feature frequencies reflecting equipment fault are varying with the work condition, and system transfer function also changes instantaneously. Affected by these factors, the signal nonlinear coupling relationship and coupling degree also change instantaneously, which brings new challenges for fault feature extraction. Therefore, study on dynamic signal feature extraction method and fault diagnosis under varying operating condition is not only of the theory and engineering prospect, but also the frontier science problem in mechanical fault diagnosis field in recent years. In this project, dynamic signal nonlinear instantaneous coupling mechanism in varying operating condition is investigated firstly, on this base, an adaptive instantaneous wavelet bispectrum is proposed for nonlinear instantaneous coupling feature detection of the dynamic signal. After that, a varying operating condition fault diagnosis method is established by using the nonlinear instantaneous coupling feature of the dynamic signal. Those methods developed in this project could not only form a solid foundation for the state evaluation and fault diagnosis of machinery in variable operating conditions, but also provide a guideline for the healthy monitor of the key components such as gearbox, rolling element bearing, ball screw and so on.

英文关键词： Nonlinear instantaneous coupling;Feature extraction;Instantaneous wavelet bispectrum;Fault diagnosis;Variable operating conditions