Methods for Reducing Vertical Carbody Vibrations of a Rail Vehicle : A Literature Survey

Abstract

The trend towards higher rail vehicle speeds generally results in increased vibrations in the carbody, which has a negative impact on ride comfort. Carbody vibrations can be reduced either by focusing on the structural stiffness of the system or by optimizing the damping components. When a conventional passive damping system cannot be further optimized, active components can be a solution to achieve improvements. Previous research concerning active control in rail vehicles to improve ride comfort show that significant benefits may be gained compared to a passive system. The overall goals are normally to improve, or at least maintain, ride comfort at increased vehicle speed or when running on tracks of inferior quality. Therefore, active suspension can be regarded as a cost-efficient solution if vehicle speed can be increased or track maintenance costs can be minimised. However, despite satisfactory results throughout the years, active suspension in rail vehicles has not yet made a convincing breakthrough in operational use. The main reason for the lack of success is most likely that the solutions offered so far have been too expensive in relation to the benefits gained. The purpose of this literature survey is to give an overview of previous studies regarding methods to passively or actively achieve vertical vibration reduction in a rail vehicle. The main focus is on active components.