关键词: 非线性动力学模型, 变风载, 双齿裂纹, 动态特性

Abstract: Aiming at the variable speed and changing load works characteristics of wind power planetary gear transmission system caused by natural wind,the time-varying input speed and torque of the system caused by random wind were calculated by wind speed power spectral density model,and the nonlinear dynamics model of the system was established by considering the time-varying meshing stiffness,comprehensive error and tooth backlash and other internal excitations.The dynamic response of the system with double-tooth crack of the sun gear under the excitation of variable wind load was simulated and analysis,and the influence of tooth cracks along the whole tooth width of the gear on the dynamic characteristics of the system was revealed.The results showed that the gear time-varying meshing stiffness would be decreased with tooth cracks,and the drop was more obvious as the crack deepens.When there was a root crack in the sun gear,there were components in the low order of the system order spectrum with the sun gear partial failure order as the interval,and there were some side orders equally spaced near the mesh fundamental order and its harmonic components.The amplitude increased with the propagation of the crack.The structure of the low-frequency component and sideband was related to the number of healthy teeth between the faulty teeth when the sun gear has non-adjacent double root cracks,which could provide a theoretical basis for the location of the faulty tooth.

Key words: nonlinear dynamic model, varying wind load, double-tooth cracks, dynamic characteristics