Reserch On Vibration Characteristics And Fault Identification Of Gearbox Of Doubly Fed Wind Turbine

As one of the most important transmission parts of a large wind turbine,the health of the gearbox directly determines whether the unit can operate normally.As the wind turbine gear box working environment is relatively poor,the probability of failure is far higher than other mechanical equipment,cause the machine stop time is the longest.Therefore,it is very important to study the vibration characteristics of wind turbine gearbox under various operating conditions,find out the vibration characteristics of fault,and establish the expert library of fault diagnosis to ensure the normal operation of the wind turbine.To this end,this paper mainly carried out the following aspects of the study:(1)Derived the planetary gear box in the planetary wheel,rolling bearing failure when the vibration characteristics.The simulation simulates that the planetary gears appear when the teeth are turned off and the inner axis of the input shaft is peeling off,gear box vibration signal,drawing and FFT analyses its.The results show that the frequency of the gearbox in the event of a planetary gear failure is equal to the meshing frequency of the planetary gear,And distribution on both sides of the shaft turns frequency as the frequency of the edge band;when the rolling bearing failure,can produce obvious in bearing natural frequency accessories modulation peaks.(2)In view of the analysis of the vibration characteristics of the gear box is difficult to determine the specific type of failure,In this paper,the vibration data of the gear box under different fault conditions of gear and rolling bearing are analyzed by wavelet analysis and Hilbert envelope decomposition.And the spectrum of different fault cases is drawn on Matlab platform.The similarities and differences of vibration signal waveforms under different working conditions are analyzed and compared,and the vibration characteristics corresponding to each fault are found out.(3)As a result of a single index to the gear box for fault diagnosis,the effect is not very satisfactory,in order to more convenient and intuitive diagnosis of various fault types,Thispaper uses the Matlab platform,taking the rolling bearing as an example,the ant colony algorithm is used to take the nine parameters of the time domain and the frequency domain as the index,preliminary implementation of automatic identification and fault diagnosis of rolling bearing.