Study On The Fault Diagnosis Of Middle And Minitype Electric Machinery Based On The Wavelet Analysis

With the development of economy construction and the improvement of electric degree, electric machinery has been used in many fields of industry. When electric machinery is in fault conduction fault, power cut will happen in some places so that there is huge economy loss and important influence on society. So the study on the fault diagnosis theory and technology of electric machinery under all kinds of instance is a pledge, which makes equipments work normally. There are many kinds of electric machinery. For example, slow variety fault and sudden variety fault, electric fault and machinery fault, linearity system fault and unlinearity system fault, their ties are very complex. Fault diagnosis can get the information of beforehand alarm through the parameters, which can reflect the hidden trouble and trend measured by all kinds of technology. Furthermore, we draw a correct conclusion of the diagnosis degree and origin, so we can maintain electromotor in time and get rid of the diagnosis. And we can realize predict service and don't influence the produce.Through the Wavelet analysis and the study of wavelet analysis we can realize comprehensive diagnosis of electric fault and machinery fault.In the paper the mechanism, cause and exhibition in vibration frequency and current frequency of electric machinery are stated. Fault diagnosis is made in 750w fraction slot melt electric machinery and 22kw permanent magnet electric machinery with good frequency ability of wavelet analysis. Firstly, db4 wavelet reduction noise of original signal ,which shows the testing is good; secondly, FFT analysis does with the fault of electric machinery accidentally, and those which can't be deal with FFT are dealt with wavelet analysis on electric machinery. The result from the experiment of 22kw permanent magnet electric machinery shows that it only has electric fault: gas interval eccentricity; 750w fraction slot melt electric machinery has break of rotor twig and beaming bear coat shatter diagnosis, which is electric fault andmachinery fault. The examination shows that wavelet analysis can identify many faults at the same time veraciously.