Research On Modeling And Vibration Characteristics Of Compound Planetary Gear System Excited By Multiple Sources

Planetary gear transmission has the characteristics of large transmission ratio,stable transmission,strong carrying capacity,high power density per unit volume and mass,coaxial input and output,strong impact resistance,power splitting and confluence while transmitting power,and it is widely used Various industrial fields^[1].With the changes in the number of planetary gears and their phases and the diversification of the meshing conditions with the ring gear sun gear,the design of planetary gear systems is also complex and diverse,and there have always been some nonlinear excitations in the gear transmission system,such as time-varying meshing stiffness.,Tooth side clearance and comprehensive error,etc.,which cause large vibration and noise problems.In addition,there are also problems such as uneven load distribution in the compound planetary gear system.For these problems,this paper takes the compound planetary gear system in the integrated transmission as the research object.Under a variety of internal and external nonlinear excitations,the system establishes a bending-torsion coupling nonlinear dynamic model,from the inherent characteristics of the system,time-frequency characteristics,and stability.The coupled vibration characteristics of the system under various working conditions are analyzed from the angles of uniform load and other aspects,and the dynamic simulation results of ADAMS are compared and mutually verified,mainly including:（1）Research on modeling methods for nonlinear excitations such as time-varying stiffness,dynamic clearance and gear installation manufacturing errors in the dynamic meshing of gears,analyze the variation characteristics and influence laws of the respective nonlinear factors,and show the bending of the compound planetary gear transmission system.Torsional coupling nonlinear dynamic modeling provides accurate mathematical models.（2）Taking a RAVIGNEAUX type compound planetary gear system as the research object,analyze the bending and torsion coupling meshing deformation relationship of each meshing pair of the compound planetary gear system in the translation and torsion directions.In the compound motion coordinate system,the time-varying phase angle of the planetary gear is considered.Factors,a dynamic model of bending-torsion coupling of the compound planetary gear system under multi-source excitation is established.（3）Numerically solve the established system bending-torsion coupling dynamics model,study the characteristics of the natural frequency and mode shape of the system and the law of the influence of parameters such as moment of inertia and meshing stiffness,and study the internal and external excitations of the system The relationship between the carrier frequency,modulation frequency and sub-frequency components of the coupled vibration response is analyzed by phase diagram,Poincarémapping,axis trajectory,and maximum load factor to analyze the stability and load characteristics of the system.（4）Based on CAE software and virtual prototype technology,the ADAMS dynamic prototype model of the system was established,and the natural vibration mode and time-frequency response results of the system were obtained,and then compared with the numerical response results for comparison analysis and mutual verification.