Self-excited Vibration Analysis of Wheelset Transverse Movement and Shaking Head in Rolling Stock

Abstract The serpentine motion of the vehicle wheelsets produces automatic guidance, but the violent serpentine motion destroys the stability of the lateral motion of the rolling stock, and even serious accidents occur. In order to judge the serpentine instability, countries follow the acceleration at different frequencies, such as China, Australia and UIC/EN adopt 10 Hz, and the United States adopts both 10 and 15 Hz, while TSI utilizes a frequency range of 3 to 9 Hz; through the coupling analysis of the transverse motion of the single-axle bogie and the rocking-head motion, the two motions form a negative feedback with each other, but with the increase of speed, the However, as the speed increases, the phase angle hysteresis also increases, and when the phase angle hysteresis exceeds π/2, the negative feedback becomes positive feedback, resulting in self-excited vibration of the wheelset. The study analyzes the relationship between gain and phase during self-excited vibration, as well as the frequency of self-excited vibration under different suspension parameters, and analyzes the critical speed of rolling stock from the perspective of the control system.