Study Of The Current Characteristics In Three-phase Squirrel Cage Asynchronous Motor Fault State And Experimental Verification

The performance of asynchronous motor is excellent,and it is widely used in industry.Therefore,the state monitoring and fault diagnosis of asynchronous motor has always been the focus of research at home and abroad.However,the existing research has not developed to the degree of industrial application,and the demand for motor state overhaul is increasing.In this paper,the fault diagnosis technology of asynchronous motor is summarized.Aiming at the defects of existing technology,this paper studies the state monitoring and fault diagnosis method based on stator current.The experimental platform is set up to verify the relevant theories.The details are as follows:(1)Common fault of asynchronous motor and its characteristic analysis and modeling.Starting from the basic electromagnetic relation of asynchronous motor,analyzes the rotor broken bars,air-gap eccentric,bearing fault reflecting the characteristics in the stator current signal,and its operation under the normal and abnormal state of modeling analysis.(2)Research on application of current signal spectrum analysis technique in motor fault diagnosis.Based on the feature harmonic spectrum analysis of the mechanical faults,the online monitoring and the fault diagnosis,starting with the disturbance of the gas gap,the basic principle,extracting the corresponding fault characteristics,and applying it to the state monitoring and failure diagnosis of the asynchronous motor.Using the ANSOFT Maxwell simulation software to make the finite element motor model,the simulation of the ANSYS Simplorer software,which is the mechanism of the electrical fault of the motor,is modeled and emulated,using the rapid addition of the window Fourier transform to do a spectral analysis of the staten current,to test the validity and feasibility of the analysis method of the diagnostic method of the diagnostic motor,and analyze the simulation results.(3)Test platform construction and experimental verification.The experimental platform was set up,and four different types of motors were verified by the data acquisition unit.Various fault current data of each model are analyzed respectively.The signal spectrum of each fault is summarized.