Abstract:In order to satisfy the safety stability-margin requirements of the new-generation high-speed bogies, based on the exploration of bogie frame acceleration alarm, the yaw soft constraint solutions and their technical implementation steps were presented. The running stability analysis is the synthesis evaluations included critical velocity and dynamical behavior. The critical velocities depend on the W/R matching features, and are influenced remarkably by the non-linear variation of both W/R contacts and bogies. The dynamical behavior evaluations are the safety index ones of bogie’s frame lateral acceleration, etc. Due to the anti-hunting dampers having the high-frequency blowing-off mechanism, the safety limits can also be reached or exceeded by the dynamical behavors of trailer bogies in spite of the small amplitude of hunting wheelset under the subcritical bifurcatuion. The frequency response analyses of bogie’s frame lateral accelerations show that the hunting oscillation is the main resonance in their vibration frequency responses, which can be controlled by the yaw soft constraint solutions.