Fault Feature Extraction Of Rotating Machinery And System Development

Nowadays, fault diagnosis of rotating machine is one of the quickly developed emerging technology at home and abroad, Research and application on monitoring and analyzing system of vibration for large rotating machine is significant to avoid substantive economic loss and disastrous accident. In the development of fault diagnosis technology, the information extraction of fault feature is found to be the most important and difficult problem, and is also the key of the problem. This is the bottle neck of fault diagnosis,and directly govens the accuracy of fault diagnosis and the reliability of early diagnosis. To solve this problem completely, signal processing is the necessary academic and technical methods to explore new path of fault feature extraction of mechanical systems,and develop new theory and technology of fault diagnosis. From the viewpoint of the goal, we make the vibration signals as our object investigated,and this dissertation studies the theories, approaches and application of signal feature extraction. The main contents of this dissertation is as follows:Chapter one briefly introduced the general situation of fault diagnosis of the rotating machine, summarizes the developing and the current situations of the technology of fault diagnosis, then outlines the main elements of dissertation and shows the overall framework of it.Chapter two gives an overview of kinds of traditional methods of technology in feature extraction of rotating machinery, and studies the basic concepts and methods of fault feature extraction techonology which based on amplitude domain analysis, time-domain analysis and Fourier transform.Chapter three researches the application of filter bank in fault feature extraction of rotating machinery, and presents an approach of construction of a two-phase conjugate quadrature mirror filter bank which can be used for vibration data precompression and transmission.Chapter four researches the mechanism and common forms of gear and rolling bearing failure. and achieves accurate diagnosis of gear and rolling bearing by using a variety of feature extraction methods which combined with the work characteristics of gear and rolling bearing.Chapter five summarizes the work of dissertation and presents the prospect.