Modeling of Vertical Vibration System of High Speed Train and Optimization of Suspension Parameters

Aiming at the optimization problem of vertical vibration of high-speed train, a six degree of freedom mechanical model of vehicle vertical vibration is established based on train dynamics principle, and the mathematical model of vehicle vertical vibration is established by using Lagrange equation. On this basis, the dynamic performance of the car body is analyzed. The undamped modal analysis is carried out to obtain the vibration response of different structures under external excitation. Frequency response function matrix is constructed, and amplitude-frequency characteristic curve is obtained. The time - domain analysis of the carriage vibration is carried out and the damping effect of suspension is verified. Then, the control variable method is used to analyze the influence of different suspension parameters on the vertical vibration of the carriage. The results show that reducing the stiffness of the primary suspension and increasing the damping of the secondary suspension can effectively reduce the vertical vibration of the vehicle body. Finally, based on the analysis of root mean square value of weighted acceleration, specific optimization suggestions of suspension parameters are put forward, which provides help for the design of train suspension system.