Dynamic analysis of multi-nonlinear coupled planetary gear induced by crack degradation
ZHU Zhijie
JIANG Hong
ZHANG Xiangfeng
CUI Chaochao
Abstract：[Objective]Aiming at the problem that the potential energy method focuses on improving the calculation accuracy of gear meshing stiffness but ignores the influences of inter-tooth coupling,gear dynamic deflection and load on meshing stiffness,the dynamic analysis of multi-nonlinear coupled planetary gear induced by crack degradation was carried out.[Methods]Firstly,the meshing of normal teeth was divided into 4 stages and the meshing of cracked teeth was divided into 7 stages by the finite element method,and the excitation effects of load and crack fault on the stiffness of gearbox were clarified.Secondly,the meshing stiffness of normal teeth affected by load was parameterized by piecewise function,and the influence law of load on single and double tooth meshing intervals was quantified.Then,a lumped mass dynamic model of planetary gear system was established by comprehensively considering nonlinear factors such as time-varying meshing stiffness,variable tooth side clearance,support bearing stiffness and damping induced by crack fault.Finally,a wind power planetary gearbox test bench was built to verify the effectiveness of the established model.[Results]The results show that based on the convergence load,the gear contact ratio increases by 8.47%and the single tooth meshing area decreases by 42.09%with the increase of load.The crack fault has a significant influence on meshing stiffness in the small load range of 10-50 N·m,with the maximum average error reaching 3.85%,and the error converges to 0.68%when the load exceeds 100 N·m.The sun gear crack fault generates sidebands spaced by the sun gear rotation frequency on both sides of the meshing frequency and its harmonics.The simulation results are in good agreement with the test results,which provides a reference for the time-frequency domain analysis of planetary gearbox fault diagnosis.
Keywords：Planetary gearMeshing stiffnesTooth root crackFinite elementLoad
Publication Date：2026-06-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：9( 34-42 )