【作者】 唐秋杭；

【导师】 朱善安；

【作者基本信息】 浙江大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 滚动轴承是旋转机械中使用最多、最为关键,同时也是最易被损坏的机械零件之一。轴承的好坏对机器工作状况的影响极大,许多旋转机械的故障都与滚动轴承的状态有关,所以对轴承进行状态检测与故障诊断是十分必要的。 本文在对轴承振动检测以及故障诊断技术的发展、现状和趋势有较全面了解的基础上,提出了共振解调法和小波多尺度分析的方法,从滚动轴承振动信号中获取故障特征信息,有效地实现了滚动轴承的故障诊断。 本论文主要完成的工作如下: 论文总结分析了滚动轴承典型故障的机理及其振动类型,详细介绍了滚动轴承振动诊断方法;简要介绍了滚动轴承的简易诊断方法——时域特征参数法,对该方法中的信号预处理部分和时域特征指标作了简要的分析,并用该方法对故障轴承进行了简易的检测。 论文还介绍了目前轴承诊断中较为成熟的共振解调法,详细介绍了该方法中的三个最重要的环节:滤波器的设计、包络解调和频谱细化,给出了该方法基于matlab的仿真和基于DSP的实现。经过对大量实测数据的处理和分析,证明该诊断方法的诊断结果是令人满意的。 最后,本文简要地介绍了小波的基本理论,针对共振解调法中因不同类型轴承故障特征频率的不同,需要相应地设计不同中心频率的带通滤波器这一问题,为了简化程序,提出了基于小波多分辨分析和信号重构技术的包络分析法。该方法通过采用不同的小波尺度因子,实现了具有不同中心频率和带宽的带通滤波器,可对振动信号在不同的频率范围内进行分析,对轴承这类非平稳信号是一种很好的处理方法。本文给出了该方法在Matlab上的仿真,详细地介绍了Mallat算法在DSP上的实现,并将该方法应用于实际的嵌入式轴承检测系统上,取得了较共振解调法更好的诊断结果。更多还原

【Abstract】 Roller bearings are one of most used and important mechanical parts in rotating machines, and vnlnerable to damage. Many faults of rotating mechanism are related to the state of roller bearings. The performance of roller bearings directly affects the performance of the whole machine. Thus, developing state testing and fault diagnosis of roller bearings is necessary.Based on the understangding of bearing vibration test technology and bearing fault analysis theory, this thesis puts forword the the rolling bearing fault diagnosis method of the resonance demodulation and wavelet analysis. In these methods, characteristic information for faults is gained from rolling bearing vibration signals. By using these methods, valid results are obtained.This thesis analyzes the fault principle and the fault vibration types. The means of the fault diagnosis of the rolling bearing are also introduced in detail. This thesis introduces the method of the fault diagnosis of the rolling bearing baesd on some character parameters. In this method, the part of pretreatment and character parameters in domain are introduced briefly. We give a simple bearing test by this method.Then, this thesis presents the method of resonance demodulation, which includes the design of filter, envelop demodulation and spectrum zooming. This thesis gives the simulation of the method based on matlab and the realization on DSP. Throuth processing and analysis of many data, the diagnosis result is satisfactory.Lastly, we know that different types of bearings have different character frequencies, so in the method of resonance demodulation, it is needed to design different band-pass filters. In order to predigest the program, an envelope analysis approach based on wavelet multiresolution analysis and reconstruction is proposed. This method adopts different wavelet genes, so it can carry out different band-pass filters which have different center frequency and bandwidth. This method is very applicable in nonstationary vibration signals, such as the bearing signals. This thesis introduces the basic theory of wavelet, and gives the simulation of this method based on matlab and presents the realization of the method on DSP. This method is applied into the embedded bearing fault diagnosis system, and gets better diagnosis result than the method of resonance demodulation.更多还原