Research On Fault Of Rolling Bearing Of CRH Based On Resonance Demodulation Method

Rolling bearing is one of the important parts of EMU,and its good working condition is an important guarantee for the safe operation of the train.The rolling bearing fault is greatly harm of train operation,so bearing diagnosis is particularly important.At present,there are many methods of bearing fault detection such as temperature analysis,vibration analysis,oil sample analysis,noise analysis,acoustic emission diagnosis,etc.The vibration analysis is the most common one in rolling bearing detection.Vibration analysis is suited to various types of bearing fault detection method.Its signal processing is relatively simple and detection result is highly accurate,and it is detected more effectively for early fault,so vibration analysis method is used to research on bearing fault detection system.There are many vibrations signal analysis method,but the resonance demodulation method is selected in this thesis,and it is used to research and analyze the bearing fault detection.Firstly,the common failure forms and the causes of the bearing are introduced.What is the difference between undamage and damage of vibration is understood,at the same time,the characteristics of vibration signals under different failure modes are also analyzed.All of those are used to the next research of vibration as the theoretical basis.Secondly,Using Sensor resonance is activited by the high frequency component what is engendered by the low frequency impact caused by the fault in the operation of the bearing,and then the high frequency resonance wave is demodulated.At last,the amplitude and frequency spectrum of demodulated resonance wave are analyzed to determine the fault location.All above these are operational principle of resonance demodulation method.The method of empirical modal decomposition is used in this thesis because of the shortcoming that the resonance demodulation method cannot judge accurately the fault.The accuracy of bearing fault diagnosis is greatly improved through the combination of these two methods.MATLAB software is used in this thesis to realize the analysis of bearing fault data of these two methods.Finally,all kinds of fault type data are provided by experiment that base on the advantage of vibration method in fault diagnosis of rolling bearing,and Visual Basic software is adopted to design the bearing fault diagnosis system,it includes call MATLAB software analyses the signal graph and access to the database.The design of the diagnostic system includes the following functional modules such as signal processing and diagnosis module,information processing module,test report save and print module,system management and maintenance module.It can be used to judge whether it is fault and the fault location through the simulation analysis of test data is realized by the system.