Vibration Features of High-speed Train Gearbox Induced by Bearing Fault

Gearbox, as one core component of the driving system of the high-speed train, consists of five sets of bearings besides the gear pair. Gearbox bearings should bear heavy loads and transfer motions, while subjecting forced vibrations and inducing coupled vibrations with gears. For the complicated structure and multiple excitations of a gearbox, bearing faults are easy to generate. In this study, a novel dynamic model of high-speed train bearing-gear system is established to delve into the vibration features of gearbox induced by bearing faults. Compared with existing studies, this model exhibits advanced integrality and accuracy. It covers all bearings in the gearbox while considering the nonlinear factors (e.g., the backlash, time-varying stiffness and error of a gear pair as well as the radial gaps, azimuth angle of bearings). The vibration responses of gearboxes with healthy and faulty bearings are calculated, and the fault vibration features are revealed.