Research And Application Of Vibration Motor Fault Diagnosis

Vibration motor as the main excitation source is widely used in various types of vibration machinery,the use of vibration machinery in modern social industrial production is gradually increased,the production efficiency,accuracy and safety requirements are getting higher and higher.Due to excitation source failure resulting in the shutdown or even a security accident occurred.Therefore,it is very important to study the on-line condition monitoring and fault diagnosis of vibration motor.This paper summarized the different methods of on-line monitoring and fault diagnosis of motor based on the extensive of reading the literature at home and abroad.At the same time,it is found that the fault analysis and diagnosis of vibration motor have not been studied clearly and concretely.In view of this situation,this paper takes the double-shaft vibration motor as the research object,and puts forward the nonlinear air gap eccentricity of the vibration motor itself,and made a detailed analysis of the type of motor in the normal state and the fault state respectively.The mathematical model of the motor is established and the simulation analysis is carried out,and built the on-line condition monitoring and fault diagnosis system of the vibration motor.In this paper,the force and air gap of the rotor spindle are analyzed in detail,and the calculation formula of the gas field length of the vibration motor is put forward.Based on the basic electromagnetic principle,it is concluded that the vibrating motor generates the characteristic component of f1±fr in the stator current during normal operation.And three kinds of common faults of the vibration motor: rotor breaking bar,inter turn short circuit and air gap eccentricity are analyzed theoretically.The causes of the three faults and the influence on the stator current are obtained respectively.The inductance calculation method of the vibration motor is put forward according to the calculation formula of the alternating current motor.The alternating current motor multi-loop theory and MATLAB software are used to simulate the normal state and the fault state of the vibration motor respectively.The results are in agreement with the theoretical analysis.Developed a vibration motor on-line status monitoring and fault diagnosis system,current transformer,date acquisition cards and computer form the hardware part which is used to vibration motor stator current signal acquisition,using Lab VIEW software to build the system's front panel and complete the background programming.The whole system includes the real-time acquisition of the stator current signal of the vibrating motor and the FFT analysis of the current signal.At the same time,the current waveform and the spectrum are displayed on the front panel.Combined with the result of the theoretical analysis,the fault type identification module is added in the system,the rotor bar broken of the motor and the air gap eccentric diagnosis,and finally the vibration motor was monitored and diagnosed.