torsion, shafts, drives, gears, vibrations, wheels, elastic constants, railways, natural vibration frequency, wheel, torsional vibration characteristics, high-speed train drive system, torsion vibration, transmission system, motor, universal shaft, gearbox, mechanics model, torque input, torsion angle displacement, angular displacement, torsion stiffness, electromechanical coupling system, Engineering (General). Civil engineering (General), TA1-2040

The high-speed train transmission system is a complex electromechanical coupling system, which consists of a motor, a universal shaft, a gearbox, and a wheel set. In order to solve dynamic problems such as torsion vibration caused by a high-speed train transmission system, the simplified model and equivalent mechanics model of the system were established, the natural vibration frequency was solved, and the simulation results of the system under a fixed torque input were analysed. The results showed that the natural vibration frequency of the universal shaft was 4.19 Hz, the natural vibration frequency of the pinion was 7.54 Hz, the natural vibration frequency of the big gear was 35.6 Hz, and the natural vibration frequency of the wheel set was 107.45 Hz. The natural vibration frequency of each part of the system increased gradually during the transmission from the motor to the wheel set. A fixed torque was added to the input end of the simulation model. The simulation results showed that the change amplitude of the torsion angle displacement of the big gear and the wheel set decreases. It is known that the angular displacement caused by the torsional vibration is weakened by the larger torsion stiffness of the axle.