Study On Dynamic Property Of Airspring Vibration Isolation System Of High-Speed Train

Vibration control includes two aspects:vibration absorption and vibration isolation. And vibration isolation means that some vibration absorbers should be fixed between vibration source and equipments which need vibration isolation. So the vibration will be isolated or weaken. And air-spring is a vibration absorber which has been used widely. It is mainly used in the suspension system of railway vehicles and highway vehicles. At present, the air-spring suspension system has been used as the secondary suspension on bogies of EMU and metro vehicles in china.Air-spring is a crucial comfort equipment on railway vehicles. It has been used widely, especially on High Speed EMU. But there are still some technical issues in the selection of air-spring parameters and application of suspension topologies. At present, air-spring is generally simplified as a simple linear spring and a linear damper in parallel when doing a dynamic simulation of vehicles with air-springs. But the simplified model can't reflect nonlinear properties of air-spring. So parameters can't be taken into account, such as effective area, connecting pipe length, additional volume and throttle diameter. Because dynamic stiffness depended on frequency and damping depended on amplitude can't be reflected, so the influence rule of air-spring parameters on vehicle dynamic properties may be not correct.At first, a single degree-of-freedom spring-mass model is established in the software simpack. And three models (simplified model, linear model, nonlinear model) are taken into account and compared. So advantages and disadvantages of each model is gotten. And a single degree-of-freedom spring-mass model with nonlinear air-spring model and half-car model of vehicle are established. The influence of air-spring parameter on air-spring system vibration isolation properties is researched.At last, mechanical equations of air-spring bellow, additional volume, throttle, connecting pipe, leveling valves and difference valves are established. And the vertical simulation model of air-spring system is established in the software SIMULINK. And the non-linear dynamic model of High-speed EMU is established in the dynamic software SIMPACK. Then the vehicle dynamic model with air-spring control system model is obtained by the use of co-simulation technology. The influence of suspension topology and air-spring parameters on vehicle dynamics are researched based on this model.Through the research of this paper, the results and conclusion of this paper can provide a good guide and reference for our country's high speed train engineering design.