Fault Simulation And Vibration Separation Of Planetary Gear In Helicopter Drive Train

As critical equipment in both civil and military activities,helicopter is playing more important role in our country,which is accompanied by the emphasis on fault diagnosis and prognosis of helicopter,as well as maintenance and logistics.However,considering weight or space,transmission train of helicopter could not be designed with redundancy,it would be severe accident once a fault occurred,even results to the death of crew members.In helicopter,planetary gear is a critical component which is directly link to the rotor,fault simulation research and fault diagnosis research on planetary gear would be meaningful for condition monitoring and fault diagnosis of helicopter transmission train.Funded by the project “Research on Damage Prognosis and Its Performance Metric Evaluation for Critical Dynamic Mechanical Components of Helicopter”,a project supported by National Natural Science Foundation of China,fault simulation and vibration separation of planetary gear is studied in the thesis,the main contents include:(1)Fault mechanism and fault mode of planetary gear is analyzed;fault simulation model for planetary gear is developed based on fault related vibration character analysis,which builds up the foundation for follow-up works.(2)Meshing regularity of planetary gear is studied;unified framework of vibration separation method for planetary gear is developed according to the vibration feature of planetary gear.(3)Research on simulation and fault-seeded experiment is carried on to validate the fault simulation model proposed in the thesis,as well as vibration separation method.Following the research planet of ‘theory study-simulation analysis-experiment verification’,fault simulation models and fault diagnosis methods are summarized in this thesis,a fault simulation model for planetary gear is proposed based on meshing regularity analysis,vibration separation method for fault diagnosis of planetary gear is developed in this thesis as well.Fault simulation signal and fault-seeded experimental signal are used to validate the effectiveness of the fault simulation model and vibration separation studied in this thesis.The research in this thesis could be the basis of further research on condition monitoring and fault diagnosis of helicopter transmission train.