Conference article

This article describes the main differences between level 1-3 in the new European signaling standard ERTMS and conventional signaling systems focusing on communication differences, the ability to look ahead and braking curves. Based on this description, the capacity differences between level 1 and 2 are investigated for theoretical as well as real-life cases using line headway calculation models developed for the study. The results show ERTMS level 2 generally has shorter headways than level 1 and hence higher capacity. However, in homogeneous operation where the braking distance is well-adapted to the block lengths, level 1 can have shorter headways than level 2 due to less system delays. The results also show that Level 2 due to continuous update of the Movement Authority (MA), result in higher capacity than level 1 for longer block sections and lower speeds. The article discusses that a 1:1 replacement of conventional signaling with ERTMS can lead to loss of capacity as the ERTMS braking curves are likely to be longer. The article also discusses how extra capacity can be gained with ERTMS as it is possible to look more block sections ahead.

Railway capacity, Signaling, ERTMS, ETCS, Braking curves