Abstract: A new non-linear dynamic model of the air spring system(TPL-ASN model) includes the sub-models of the orifices, the connecting pipes and all the chambers is established based on the theories of aerodynamics, fluid mechanics and engineering thermodynamics, etc. Three quarter-car dynamics simulation models respectively include the equivalent model, the linear model and the TPL-ASN model are set up using the dynamics simulation software SIMPACK and the self-designed air spring dynamic characteristics simulation software ASDS. The dynamic characteristics of a high-speed electric multiple unit(EMU) air spring are calculated under different excitation amplitudes and frequencies, and take the simulation results of the dynamic stiffness, the damping ratio and the transmission ratio compare with the experimental results. Results show that, the simulation results of the equivalent model and the linear model have great difference with the experimental results, the two models can not accurately reflect the amplitude characteristics and the frequency characteristics of the dynamic stiffness, the damping ratio and the transmission ratio, but the simulation results of the TPL-ASN model are in good agreement with the experimental results. All the results show that the TPL-ASN model can accurately simulate the air spring non-linear dynamic characteristics.

Key words: air spring, amplitude characteristics, frequency characteristics, model, non-linear