Abstract
Some conventional railway tracks are subject to lower maintenance criteria, unlike Shinkansen lines. This usually implies large vertical irregularities and/or depressions at the rail joints, which are a known cause of vertical rigid-body-mode vibration of the car body. Since suppressing such vibration is necessary for improving ride comfort, a secondary suspension damping force control system with variable vertical dampers (a vibration control system) is being developed. For improving the performance of vibration suppression of the system, this paper proposed a control technique taking into account forced vibration caused by running through depressions at the rail joints. While the vehicle runs at a constant speed, the frequency of the forced vibration stays constant. Therefore, the weighting functions for controlled variables are set with a large value at the frequency so as to reduce the forced vibration selectively. Numerical simulations using 7-DOF vehicle model with variable secondary vertical damper were carried out, and the proposed algorithm can effectively suppress vertical rigid-body-mode vibration of the car body.
