| Gears or gearboxes have the function of transmitting movement and adjusting speed,and have a wide range of applications and play a vital role in the machinery manufacturing industry.However,some equipment such as wind turbines,high-speed trains,and highspeed ships often fail due to their unstable working environment,and gearbox failures account for a high proportion and are more harmful.Therefore,the failure analysis of gearboxes is very necessary.The traditional fault tree analysis method has great advantages in analyzing the causes of gearbox faults,but this method is lacking in the dynamic propagation analysis of gearbox faults.Petri nets have dynamic characteristics and have obvious advantages in the analysis of the dynamic propagation process of gearbox faults.Monitoring equipment such as sensors can monitor the real-time status of the gearbox,which can help with the health management and fault diagnosis of the gearbox.This paper takes a certain planetary gearbox as the object,combines fault tree analysis,Petri net and condition monitoring technology to carry out dynamic research and analysis of gearbox faults.The specific research content is as follows:(1)Carry out fault tree modeling analysis with planetary gearbox as the object.Carry out the fault tree modeling work for the planetary gearbox,and use the ascending method to find the minimum cut set of the fault tree and solve the structural importance.(2)Carry out fault tree-Petri net modeling analysis for planetary gearbox system.Aiming at the problems that traditional fault tree analysis cannot reflect the dynamic process of various state changes in the system,Petri nets are introduced to carry out fault tree-Petri net modeling analysis for planetary gearbox systems.The Petri net model of the planetary gearbox fault tree is established,and the incidence matrix method and state equation are used to realize the dynamic propagation of the planetary gearbox system fault.(3)Taking the gears in the planetary gearbox as the object,the fault tree and Petri nets are used to model and analyze the degree of gear failure.The fault degree tree of the gear is established,and the fault degree tree model is transformed into a fault degree treePetri net model.(4)Combine the condition monitoring with the fault degree tree-Petri net model to carry out the real-time dynamic analysis of the gear status.Use the fault diagnosis technology based on vibration analysis to analyze the data,feed back the analysis results of the fault diagnosis to the fault degree tree-Petri net model,and analyze the gear status in real time. |
