Vibration Signal Simulation And Localized Fault Diagnosis Of Planetary Gearboxes Based On Transmission Mechanism Analysis

As a kind of key equipment focusing on changing speed and transmitting power,planetary gearboxes has been widely used in various fields such as military,industry,life etc.As the same time,it is difficult to estimate the loss caused by the fault(s)of planetary gearboxes.Compared to fixed-axis gearboxes,the mechanical structure and transmission structure of the planetary gearboxes are more complex.In addition to the percentage of localized gear fault is the largest in all kinds of planetary gearboxes fault(s).Therefore,localized gear fault of planetary gearboxes is the object of study in this paper.In planetary gearboxes,“the vibration response of multiple gear meshing couple with each other” and “the vibration transmission paths from gear meshing points to the fixed transducers are time-varying” are two special characteristics.Therefore,it is more difficult to do fault diagnosis in planetary gearboxes than fixed-axis gearboxes,so that “going deep into analyze fault(s)problem based on transmission mechanism” and “reasonably constructing the vibration signal model” is the key to solve the localized gear fault diagnosis problem of planetary gearboxes.And it is the task in this research.According to the background of the task above,I finished four parts of works which providing new ideas about related work or improving the existed results.(1)According to the transmission mechanism analysis,simulated the gear meshing process of sun,planet gear localized fault point in planetary gearboxes.Summarized the time-varying rule of meshing position,and improved the time-varying equation.(2)Summarized the equations of sun,planet gear localized fault tide frequency based on the localized fault characteristic frequency of planetary gearboxes(meshing frequency,rotating frequency of carrier,localized fault frequency).(3)Added the sun,planet localized fault tide frequency to the vibration signal simulation of planetary gearboxes.Established the improved vibration signal simulation of planetary gearboxes,and analyzed the frequency spectrum.(4)To validate the correctness of the preceding three parts works,accomplished the localized fault diagnosis of planetary gearboxes.Designed the fault experiment to analyze the truth localized fault signal of planetary gearboxes,and compared with the theory above.This research demonstrated the applicability of the running rules,characteristic frequency,simulation signal to the localized fault diagnosis of planetary gearboxes through the comparison of the simulation and experiment.And the results can be viewed as a valuable reference for the research and development of planetary gearboxes fault diagnosis.