| With the continuous development of science and technology,more and more mechanical equipment is widely used in the production and life,and the safety of mechanical equipment has gradually received people’s attention.As the core component of energy conversion of many mechanical equipments,once the fault occurs in the operation process,it will definitely have a huge impact on the whole mechanical system,resulting in incalculable economic losses.Bearing failure is the most common and most prone to mechanical failure in motor failure.When the bearing fault occurs at the same time with other faults,such as motor broken bar fault or load system bearing fault and motor bearing fault coupling,complex strong and weak fault characteristics appear,which causes the difficulty for motor bearing fault diagnosis.The motor bearing is taken as the research object,and the fault characteristics of the motor bearing coupled fault vibration signal under different working conditions are studied.In this paper,the motor bearing is taken as the research object,and the fault characteristics of the motor bearing coupled fault vibration signal under different working conditions are studied.Development of bearing-coupled fault diagnosis system for induction motor based on wavelet-spectrum kurtosis using virtual instrument LabVIEW software development platform.Firstly,this paper studies the fault feature identification of the coupling problem between motor bearing and load bearing.By analyzing the kurtosis value and envelope demodulation results of the coupled fault vibration signal,it is found that the vibration energy of the motor bearing fault characteristic frequency is reduced under the coupling of the fault characteristics of the load bearing and the motor bearing fault characteristics,and the performance of the weak fault is not obvious.The Hilbert demodulation method can extract the strong fault features in the coupling fault,in stand of all fault features.In this paper,the wavelet-spectral kurtosis method is proposed to extract the characteristics of the motor bearing coupled fault vibration signal.The analysis results show that the wavelet-spectral kurtosis can simultaneously extract the strong and weak fault features in the coupled fault.Secondly,the fault feature identification of the motor broken strip and motor bearing coupling fault is studied.In the vibration signal analysis,the power frequency modulation of the motor caused by the broken bar fault increases the side frequency component of the power frequency and the power frequency in the spectrum,and the vibration energy at the characteristic frequency of the motor bearing fault is weakened;In the current signal analysis,it is difficult to extract the characteristic frequency of the motor bearing fault due to the influence of the power frequency modulation.The traditional analysis methods of both signals can only extract strong fault features.In this paper,the method of wavelet decomposition and spectral kurtosis is used to analyze the coupling fault signal of motor broken strip and motor bearing.The vibration signal analysis results show that the wavelet-spectral kurtosis method can simultaneously identify the fault characteristics of motor broken strip and motor bearing.Finally,using the virtual instrument LabVIEW platform,the design and development of the fault diagnosis system for induction motor bearing based on wavelet-spectral kurtosis is realized with softwares LabVIEW and Matlab.And the feasibility and accuracy of the system is proved by experimental data. |
