Adaptive stability mechanism of high-speed train employing parallel inerter yaw damper

Abstract

The aim of the study is to design a secondary yaw suspension that will control both low-frequency body motion and bogie hunting under different wheel–rail equivalent conicities. In order to enable the high-speed train to adaptively adjust to different wheel tread wear stages and improve the lateral dynamic performance of the vehicle in extreme wheel–rail contact states without any sensors and control systems, the eddy current damper with the parallel inerter as the yaw damper is proposed, and the in-depth research on its working mechanism is conducted. By establishing the theoretical analysis model of the lateral dynamics of high-speed train, and the multi-objective optimisation of the vehicle performances is carried out. The optimal parameters of the yaw damper under different wheel–rail contact conditions are analysed and the importance of frequency-dependent stiffness of yaw damper is obtained. Based on the characteristics of high-frequency transmissibility of inerter, the parallel inerter is applied to solve the limitation of insufficient dynamic stiffness of the traditional hydraulic yaw damper. The parameter configuration of the yaw damper with small series stiffness and large parallel inerter is proposed, and the stable operation of trains in major wheel–rail contact equivalent conicity is realised by using its frequency-dependent stiffness characteristics. In addition, the optimal energy dissipation and negative stiffness conditions of the parallel inerter yaw damper are analysed in this paper.