Vibration And Control For Undeframe Suspended Equipment Of High Speed Trains

By the end of 2015, the operation length of China’s high-speed railways has surpassed 19,000 kilometers, and in the upcoming years China’s high-speed railways will certainly develop further. High-speed railway aims to fulfill the principles of safety, comfort and rapidness, and its development requires technological support from various perspectives. While carbody underframe suspended equipment, which usually weighs eight to ten tons, has significant influence upon the dynamic performance of train operation. This thesis aims to study the vibration characteristics and control of high-speed trains’underframe suspended equipment. And a semi-active vibration damper is proposed to be installed between carbody and underframe suspended equipment, in order to control the transmitted vibrations from underframe suspended equipment to carbody. Moreover, a spring and damp absorber is considered to install between suspended equipment and the vibration features of carbody and underframe suspended equipment are investigated.Firstly, the thesis presents a review on high-speed railway’s development history and high-speed trains’ vibration issues, and then introduces the application of rigid-flexible coupling dynamics, as well as the approaches and utilization of vibration control for the carbody underframe suspended equipment.Secondly, the rigid-flexible coupling dynamics model of vehicle system is established by using the dynamic simulation software SIMPACK and the coupling vibration features of carbody and underframe suspended equipment are studied, The ride performance and running safety of the vehicle system are analyzed, and the vibration transmission features between wheelset, bogie frame, carbody and underframe suspended equipment are investigated. Furthermore, the impact of active suspended equipment on carbody’s vibration is studied and the vibration isolation method is suggested.Then, the influence of semi-active control on the coupling vibration of carbody and underframe suspended equipment are studied. A semi-active damper is installed between carbody and underframe suspended equipment, the vibraton reduction characteristics under harmonnic excitation and actual track irregularity excitation at different operation speed are analyzed.Finally, the installation of a damping device between underframe suspended equipment is considered, and its damping features for carbody and underframe suspended equipment at different operation speeds are analyzed, and the stiffness parameters are studied.