Research On Fault Diagnosis Method Of Wind Turbine Gearbox

With the development of human society,global energy shortages,environmental pollution and other social problems have become increasingly prominent.Wind energy has become one of the key energy sources in various countries due to its abundant reserves,clean and environmental protection,and renewable.The research shows that the frequency of faults in the wind turbine drive system is high,and the damage caused by this fault is the most serious.Therefore,the research on the gearbox of the key components of the wind turbine(referred to as: wind turbine)transmission system is especially important.Based on the analysis of wind turbine gearbox failure data,this paper studies the fault feature extraction method of wind turbine gearbox under complex conditions to realize the accurate diagnosis of wind turbine gearbox failure.The main work of this paper is as follows:1.Based on the introduction of the common failure modes and vibration mechanism in the gearbox,the gearbox fault data of a 750 KW wind turbine is analyzed.Then,the diagnosability of each fault in the wind turbine gearbox is classified and summarized against the results of the disassemble test.2.Aiming at the weak fault of the gearbox,the wavelet envelope spectrum and the fast Kurtogram are used to analyze the fault data of the wind turbine gearbox,and the fault of the outer ring of the medium-speed shaft motor bearing is diagnosed.At the same time,the fault characteristics is also enhanced.The fault characteristics of the high-speed shaft motor side bearing inner ring,the high-speed shaft impeller side bearing cage and the medium-speed shaft impeller side bearing inner ring were extracted.Among them,the fault characteristics of the inner ring of the high-speed shaft motor side bearing,the middle-speed shaft motor side bearing outer ring and the medium-speed shaft impeller side bearing inner ring extracted by the wavelet envelope spectrum are obvious.Although the fault characteristics of the high-speed shaft motor side bearing inner ring,the high-speed shaft impeller side bearing cage and the medium-speed shaft motor side bearing outer ring are extracted by the fast Kurtogram,their fault characteristics are relatively weak.But the High speed shaft impeller side cage failure that is not diagnosed by the wavelet envelope spectrum is diagnosed.3.For the weak faults that have not been diagnosed by other methods,their fault signal can be highlighted by Cepstrum pre-whitening(CPW).So the bearing fault diagnosis method combining CPW and wavelet envelope spectrum is proposed.This method not only successfully diagnoses the bearing faults diagnosed by other methods,but also successfully diagnoses the outer ring fault of the planetary carrier impeller side bearing that has not been diagnosed by other methods,and their fault features has lessinterference components and clearer,which proves the effectiveness of the method.