Research On Fault Diagnosis Method Based On Vibration Energy

With the development of science and technology, modern mechanical equipment is moving toward the maximization, precision, automation, continuous, high-speed and heavy-load direction. Once the mechanical equipment breaks down, it will cause huge economic loss and may even lead to catastrophic consequences of fatal crash. State monitor and fault diagnosis can avoid excessive maintenance, lower maintenance costs, increase equipment runtime and reduce the accident rate, bring great economic and social benefits to enterprises, so more and more attention. Usually use two mutually perpendicular sensors of the same section to collect vibration information, however the traditional state monitor and fault diagnosis only use one single channel vibration information, information on any single channel is not complete and can’t not fully reflect the running status of the rotor, so it is easy to missing and misjudgment. The vector spectrum based on homologous information fuses two channels of information, the numerical algorithm is simple and robust,and can combine with traditional signal analysis methods.Large engineering applications show that the vector spectrum can fully and accurately reflect the running status of the rotor and has great advantages.In this paper, based on the vibration energy of single freedom vibration system under the harmonic excitation, put forward the ideas and methods based on vibration energy, and use it for fault diagnosis,at last combine it with vector spectrum to further expand the vibration energy method.The main content of this paper is as follows:1. Analyse the vibration energy of single freedom vibration system under the harmonic excitation, get the vibration energy and vibration power under a single frequency from this, the results show that the vibration energy can comprehensively reflect the influence of amplitude and frequency on the system.And then combine with traditional signal analysis methods in order to get vibration energy spectrum and vibration power spectrum which can fully reflect the influence of amplitude and frequency of the signal on the system. 2. First carry out the theoretical research of vibration energy and vibration fatigue life of single freedom system, then conduct fatigue life analysis of the transverse bending vibration of beam with ANSYS/FE-SAFE software. The results show that:in a certain range, the greater the vibration energy, the vibration fatigue life shorter and vice versa,so vibration energy can reflect the vibration fatigue properties of the equipment and can be used for state monitor and fault diagnosis of the equipment.3. Combine the ideas and methods based on vibration energy with traditional analysis methods,and used for state monitor and fault diagnosis of the equipment, the results show that the methods based on vibration energy is effective.4. Combine the ideas and methods based on vibration energy with vector spectrum,we can get the vector vibration energy spectrum of double channel vibration signal, then carry out the diagnosis of rotor fault and acquire a good diagnosis effect.