Preliminary Performance Test of Active Secondary Vertical Suspension using a Low Power Actuator on a Railway Roller Rig

This paper investigates a method for effectively applying active secondary suspension to mitigate vibration in the vertical direction to improve ride comfort in railway vehicles.We focus on the fact that, in modern high-speed vehicles, vibrations of higher frequency contribute relatively more to vertical ride comfort than vibrations of approximately 1-2 Hz.To effectively reduce such vibrations, we propose the use of actuators that prioritize high responsiveness over high power.To verify whether this concept is effective for real vehicles, we developed an actual prototype of a vertical linear actuator based on a linear motor system, applied it to a Shinkansen equivalent vehicle, and carried out vibration excitation tests on a vehicle roller rig.A modal skyhook control of the rigid-body mode and first-order bending mode was applied using four accelerometers mounted on the carbody floor and was particularly effective in reducing the vibration of the rigid-body mode of the carbody in the 0.5 -4 Hz range and of the bending mode around 9 Hz.The maximum force of each actuator was approximately 1.8 kN (two actuators per bogie).In this case, there was no reduction in vibration reduction performance due to the response delay of the actuators, as observed when hydraulic actuators are used.