Integrated tilt and active lateral secondary suspension control in high speed railway vehicles

The use of tilting bodies on railway vehicles is increasingly widespread with a number of well-established services using tilt technology already existing around the world. The motivation for tilting railway vehicles is that they give a cost-effective means of achieving a substantial reduction in journey time by increasing the vehicle speed during curves, without the need of building new high speed railtrack infrastructure. A tilting railway vehicle is a dynamically complex structure. Many of the dynamic modes of the system are coupled and the coupling in certain situations, i.e. coupling between the vehicle lateral and roll modes, is very significant which unavoidably causes difficulties in control system design, especially for the local vehicle control strategies. Meanwhile, the high speed results in the worse ride quality on straight track, and an effective solution is to use the active secondary suspension. This research investigated control strategies for the integration of tilt and active lateral secondary suspension. The simulation results showed the efficiency of this research on enhancing local tilting control performance both on straight and curved track. Furthermore, Multi-input and Multi-output system configuration, control and optimization, as well as model-based estimation are also investigated for this tilt and lateral actuators control system aiming to further improve the control system robustness and performance. Finally, a FPGA-based Hardware-In-the-Loop simulation system is set up with the considersion of the controller practical implementation.