INTRO: Opening of the Øresund fixed link on July 2 physically connects two railways. Ensuring that trains can pass seamlessly from one to the other at up to 200 km/h required ingenuity in integrating the different signalling, communications and train protection systems

BYLINE: Konrad Hove and Niels Brejnbjerg Buch*

WHEN commercial services are launched across the Øresund Fixed Link between Denmark and Sweden on July 2, trains will travel across the border at up to 200 km/h. Passengers on board will notice nothing as the trains change from one train control and signalling system to another, but ensuring that the border crossing takes place seamlessly represented a major technical challenge.

A team of Danish and Swedish railway experts and engineers came up with the answers. Perhaps surprisingly, they did not choose to implement the ERTMS-ETCS train control system that will one day be used widely across Europe. This is because the link is just a short connection between two existing railway systems, so introducing a third system between them would have made it even more difficult for operators to run trains directly between the two countries.

Similar links between two national railways will probably be necessary elsewhere in the future, and the Øresund consortium, together with its consultants, would like to share its knowledge with other railways.

The distance between the two shores is around 16 km. The link includes an artificial peninsula, an immersed tunnel, an artificial island called Peberholm and a bridge. Steepest gradient is 1·56%, and this is used on the approach bridges that climb up to the high bridge where there is a passage for ships up to 55m high.

In the tunnel the railway runs in two single-track tubes. On the island both tracks are located south of the motorway, and on the bridge the railway occupies the lower deck.

Several types of train will use the link. One is a 180 km/h dual-system EMU, which has been specially developed for regional services across the link. Danish State Railways is introducing its EG locomotive which has been developed to haul freight trains right through from Sweden to Germany over the Øresund fixed link and the Storebaelt crossing, which was completed in 1997. In addition, some of Swedish State Railways’ X2000 tilting trains will be modified to use the link, together with some of DSB’s IC3 diesel trainsets.

Coping with the differences

To ensure full flexibility of operations, train drivers have to be able to drive in both countries, but ensuring that this was possible was not an easy task. The safety regulations are different, and the signals have quite different meanings. To minimise the difficulties, the changeover points for the various systems were grouped at a single location as far as possible.

The so-called ’system border’ marks the limit between Danish and Swedish traffic control and is located at the western home signal of the Peberholm station. This is a merely a ’technical station’ for operating purposes, and has no passenger or freight facilities. The traffic management centre in København controls trains west of this point, plus the overhead power supply for the whole of the link . Other functions are controlled from Malm