Abstract:Based on mass induction method, state space theory and modal space theory, three methods were proposed for identifying physical parameters of the mass above the suspension of the bogie system. Designed directional excitation test conditions for physical parameter identification. The above physical parameter identification methods were verified and compared by simulation test. The results show that when using mass induction method, state space theory, and modal space theory, the additional mass size is selected as 8%, 17% and 7% of the system quality respectively, the higher recognition accuracy can be achieved. In general, the modal space theory has the highest recognition accuracy, the state space theory is second, and the mass induction method is the worst. For the identification of quality parameters, inertia parameters, vertical stiffness and damping parameters, the influence of the height between the centroid of the mass above the suspension of the bogie system and the position of the lower point of the suspension can be ignored. When the height is small, the influence of the structural parameter identification error can be ignored.