Issues of Control15 April 2008
As rail markets across Europe merge and overlap, standardisation in rail control systems is increasing apace. Drew Turney investigates.
Much like the nascent computer programme market that developed in the 1980s, witnessed by many of today's generations, the railway spread across the earth at what seemed like lightning speed in the 1800s with the invention of the steam engine. The expansion of rail networks across the Eurasian and North American continents led to an explosion in resources trading and paper wealth, not dissimilar to that of the dotcom boom a century and a half later.
Early rail was also like software development in that it happened in regional isolation – each operator, government or owner developed standards that weren't compatible with each other.
The railway gauges of America's New England region, for example, differed from the rest of the US for a long time as most of the region's rolling stock was imported from the UK.
In a new world of trade interoperability – and with the world's economy facing a downturn – it is now more urgent than ever to consider rail networks in a global sense rather than national, taking into account expanding trade and current environmental concerns.
EUROPE TAKES THE LEAD WITH COMMUNICATIONS
The first step toward a coordinated approach in Europe was the European Rail Traffic Management System (ERTMS), a programme with the stated aim of making rail that enables trains to cross borders without stopping.
The first component of ERTMS is the European Train Control System (ETCS), a specification written in 1996 after an EU council directive. Testing commenced in six countries in 1999 and the process of deployment continues. The first deployment was the high-speed Zaragoza-Huesca line in Spain in 2004. This year, the upgraded Cambrian line in the UK will pilot the system for the projected UK-wide rollout in 2011.
ETCS requires functional and equipment standards to be applied or fitted to trains under the scheme, particularly those operating on high-speed lines. It allows drivers to receive movement authority and route information on an up-to-the-minute basis. The ETCS package is termed 'EuroCab', and any train fitted with the kit can operate on any designated ETCS route without restriction.
The other component of the ERTMS is wireless mobile communications. Called the Global System for Mobile communications – Railway (GSM-R), it has been adopted by all EU member states as well as others in Asia and Africa.
The GSM-R is an attempt to move rail communications away from in-track cable and analogue radio networks by providing a single, secure digital network. It will offer voice and data communication between drivers, dispatchers, shunting team members, engineers and station controllers and has provision for services from group calls and voice broadcast to tracking, video surveillance and passenger information services.
The GSM-R will replace over 30 analogue systems across Europe, not only greatly enhancing interoperability but superseding a huge amount of cabling that is expensive to install and maintain.
The system is currently being implemented by 12 EU countries and India.
Meanwhile, three further EU countries are in planning and 11 countries are conducting feasibility testing, including the US, Russia and Australia.
The initial roll-out of the GSM-R has been using small handheld communicators not unlike mobile phones such as the Sagem TiGR 350R, but there are cab-fixed models ready for deployment from providers such as Siemens. GSM-R has already been trialled in the UK and it is estimated that the network will be operational by 2013 at a cost of £1.2bn.
The first commercial railway with full GSM-R coverage was opened in France in June 2007, linking Paris Gare de l'Est to Strasbourg via the LGV Est, and Germany's ICE train conducted the first high-speed test.
BIG NAMES BEHIND ERTMS
Providing the services of the ERTMS are some of the biggest names in European electronics and telecommunications. Alstom, Invensys, Ansaldo Signal, Alcatel, Siemens, Bombardier and others are all playing a part in developing track, cab or communications equipment and systems.
France-based Alstom describes the challenge facing the rail industry as being "[to] safely transport more passengers and freight, on the same tracks, while decreasing operations and maintenance costs."
Alstom claims to offer the solution to this problem by taking a modular approach. The company says this can be scaled depending on the needs of the network and involves incremental upgrade costs rather than a 'back to square one' approach.
Alstom's two main offerings in new generation signalling are urban (Urbalis™) and main line (Atlas™) based systems, and the company's sales points highlight the differences between the distinct needs of each kind of network.
Urban, city-based networks need heavy-load traffic regulation and a robust control centre, and needs real-time information to deliver information to passengers.
It must be aware of station equipment, the shunting or interlocking of rolling stock, trackside positioning or communications equipment, failsafe on-board communications between driver and control centre and data generated by movement authority and route planning.
By contrast, mainline networks with a higher incidence of freight traffic have quite different needs. A communications signalling system must manage interoperability with urban and industrial networks at either end of the journey, operate at speeds of up to several hundred kilometres an hour and be in constant GSM-based contact for both data and voice communication and positioning.
Increasing digitisation and standardisation in control systems is catching on around the world. In Australia, the Victorian government announced in March 2007 that the ageing state rail control apparatus was set for an overhaul. The government awarded an A$27m (£12.7m) contract to Westinghouse Rail Systems Australia.
With 11,000 services a week, the office of the Victorian Public Transport minister said the current system was perfectly adequate, but according to the department's ten-year transport blueprint, planned expansion to the rail infrastructure meant a new system was needed. The new system promised "capacity for real-time monitoring of 100% of the rail network, with capability for future expansion."
Although the benefits of the Victorian system were more concerned with delivering comprehensive timetable information to commuters in real time, other rail signalling or communication upgrade systems leverage different benefits. In a region with high rail traffic, overstretched control systems often cannot cope with the addition of new infrastructure.
In March 2005 Alcatel announced a €20m contract from the government of Shanghai to apply its SelTrac® solution to an extension of over 23km incorporating 22 stations. One aspect of SelTrac® is a wireless communications system between the track and the train, removing almost all track-embedded communications equipment and providing the capacity for other services such as on-board video surveillance to operate over the same network backbone.
Alcatel claimed the new system would simplify maintenance operations and allow the Shanghai metro system to not only operate trains at close to 90 seconds apart, but also add trains automatically during peak periods.
Improved, wireless or mobile-based communications – or ones that use the track itself as a cable – are very much the future. They will not only greatly expand capacity as rail travel becomes a more realistic option in energy-hungry times, they will also allow rail networks to exert a smaller aesthetic and electromagnetic footprint on our landscapes.