Paris-Lyon: the pilot project for a high-performance high-speed line

More, better orchestrated trains offering higher standards of service

HSL is France’s oldest and most heavily-trafficked high-speed line. At peak periods, traffic rapidly reaches saturation point. The slightest incident has an immediate knock-on regularity with thousands of passengers impacted by train delays. Its modernisation is not only one of SNCF Réseau’s priorities but also a priority for Europe, which has earmarked a €117 million contribution to its funding. Project aims are pragmatic: improved traffic regularity and punctuality, greater line capacity, even at peak hours, and adaptation to European standards (think "interoperability").

Paris-Lyon: Europe’s most heavily-trafficked line

Today, 240 trains are worked each day on the busiest section of the line, making it the most heavily-trafficked in Europe. It handles one-third of domestic high-speed traffic including trains operated on major trans-European routes with Spain, Italy and the North of Europe.

And traffic on the line is heading for further growth in the coming years. But, in its present configuration, maximum capacity has been reached. With the advent of open competition, new operators are likely to bring an extra influx of train path requests. Something must therefore be done to boost capacity on the line.

Affording fair, safe and equitable access to the Paris-Lyon high-speed line for all railway undertakings, such is the challenge that SNCF Réseau has set itself. Its strategy consists of upgrading existing infrastructure by tapping into the latest technological innovations. From 2025, it will be possible to slot a further three trains into the timetable at peak-periods. Work to transform this corridor will act as a test-bed for more general efforts to boost performance and line throughput.

European and domestic services worked via the Paris-Lyon HSL in 2019

Digital solutions

To boost performance on the Paris-Lyon high-speed line, SNCF Réseau is looking to make a major technological breakthrough by adopting a series of technological innovations for infrastructure on the line: the European Rail Traffic Management System ERTMS 2, Central Network Control (CCR) and Operation Traffic Management (GOC 2.0).

ERTMS

Already in use in other European countries, ERTMS (European Rail Traffic Management System) is the most advanced, most reliable and most robust signalling system in existence and, over the next few years, is scheduled to replace the 27 systems currently in service across Europe.

With ERTMS, train headways can be managed in real time, which releases greater capacity on the line, improves regularity and punctuality while providing the desired interoperability between European networks. At peak traffic times, the line will be able to handle 16 trains as against the present 13, courtesy of ERTMS.

This signalling technology is now about to be installed for the first time on a high-speed line in service without halting traffic flows. Investment will total over €600 million, which will cover:

• ERTMS installation as such
• interlocking replacement or adaptation
• boosting power supplies along the line
• modifying infrastructure at the entrance to Paris and Lyon to cater to the additional trains
• deployment of an environmental enhancement programme over the entire length of the line

Central Network Control (CCR)

Thousands of signal boxes and interlockings currently dotted across the country are to be controlled in future from a single point, a vast control room from which all traffic movements will be centrally managed. This should make traffic management more efficient, rationalise decision-making processes and make it easier to anticipate on potential incidents. Data will be processed in real time in a modern, ultra-connected control centre. With this new traffic control system, better orchestrated train movements will be the norm.

The three advantages of Central Network Control:

• Apposite information
  SNCF traffic controllers will be able easily to locate the precise position of individual trains, a major advantage in the event of disruption.
• Maximum regularity
  Routes will be set by computer, which will enable control room staff better to anticipate train movements and, more particularly, plan ahead to deal with contingencies.
• Response times
  All installations will be remote-monitored, which will make it easier to nip potential operating incidents in the bud.

Operation Traffic Management (GOC 2.0)

To improve train sequences on the Paris-Lyon high-speed line, SNCF Réseau is installing a new intelligent traffic control system: GOC 2.0. The system identifies trains that are running late, simulates the knock-on effects and proposes solutions to harness their impact on the line. Staff are then free to focus on train movement monitoring and incident management.

GOC 2.0 targets three objectives:

• optimising network capacity and better responding to train path requests
• anticipating conflicts and proposing appropriate solutions
• facilitating exchanges of information

Points to remember

• ERTMS is about to make its debut on a high-speed line in service without interfering with traffic flows.
• ERTMS, CCR and GOC 2.0: the new technologies forming the kingpins of the future network.
• In 2025, the Lyon-Paris high-speed line, and with it the rail system as a whole, will enter a new digital and broadband era.