Development and Simulation of an Hil Full-scale Test-rig to Study High Speed Train Dynamics under Degraded Adhesion Conditions

In this paper, an innovative Hardware In the Loop (HIL) architecture is presented to test braking on board subsystems on full-scale roller-rigs. The new approach is based on an innovative control strategy to reproduce a generic wheel-rail adhesion pattern on the roller-rig and particularly suitable for degraded adhesion conditions. The presented strategy is also implemented by the full-scale roller-rig of the Railway Research and Approval Center (RRAC) of Firenze-Osmannoro (Italy). A complete model of the HIL system has been developed based on the real characteristics of the components to validate the proposed approach. Results obtained from the simulation model have been compared to the experimental data provided by Trenitalia and relative to on-track tests performed in Velim, Czech Republic, with a UIC-Z1 coach equipped with a fully-working WSP system. The preliminary validation performed with the HIL model highlights the good performances of the HIL strategy in reproducing the complex interaction between degraded adhesion conditions and railway vehicle dynamics during the braking manoeuvre on the roller-rig.