A Space-Time Interval Based Safety Protection Model for Virtual Coupling Heavy-Haul Trains

Heavy-haul railway is one of the most cost-effective ways of transporting bulk goods globally, and enhancing its capacity is critical. The dominant method of capacity enhancement is increasing the load capacity of a single train, carrying risks of accidents. Introducing virtual coupling into heavy-haul railways is expected to solve these problems and significantly increase capacity. However, the absolute braking distance based safety protection model cannot meet the demand for distance between adjacent virtually coupled heavy-haul trains. To overcome this shortage, we propose a space-time interval based safety protection model for virtual coupling heavy-haul trains. Constraints are added to the model to ensure the two trains will not collide during the entire braking process. Aiming at the feature of long braking delay caused by the extended length of heavy-haul trains, we develop a braking wave propagation model to establish a more accurate safety braking model and shorten the safe distance between adjacent virtually coupled trains. Different safety braking models are used for the preceding and following trains to improve computational efficiency. The experimental results show that the safe distance of this model is shortened by 41.8% compared with the ABD based safety protection model at 80 km/h.