ProRail researching ‘hybrid ERTMS Level 3’ version
ProRail, together with Network Rail and SNCF, is currently looking at the possibility of using a ‘hybrid ERTMS Level 3’ version on the track. Live testing is expected to start on a track owned by Network Rail in England this October. If the testing with ‘hybrid ERTMS level 3’ is successful, it is anticipated that the costs for the implementation will be lower than with the roll-out of ERTMS Level 2. Furthermore, bigger capacity gains can be made.
During an ERTMS seminar by the Royal Netherlands Society of Engineers (KIVI) at Arcadis in Amersfoort, various experts talked about the latest developments in the European safety system. There was an in-depth discussion about the Hybrid ERTMS Level 3 version that is currently in the development phase.
Do you want to learn more about the latest developments of ERTMS in Europe? Take part in the ERTMS Conference at 28 March at RailTech Europe 2017 in the Jaarbeurs Utrecht, the Netherlands.
At the beginning of the seminar, Eelco Schrik, ERTMS expert at Mott MacDonald and chair of the event, made the provocative suggestion that it would possibly be best if the Netherlands, when making the switch to ERTMS, started using the Hybrid ERTMS Level 3 straight away. “In April 2014, the cabinet decided to implement ERTMS Level 2, but also to take account of adaptations with these sorts of technological developments. With the development of Hybrid Level 3, this commitment can be realised”, suggests Marcel van der Vliet, ProRail’s Project Manager Innovation.
The costs of the installation of a Level 2 version are certain if an increase in capacity is needed and existing detection has to be replaced or expanded, and they will probably be higher than if the Hybrid Level 3 is chosen. With the latter, capacity growth can be realised on the existing track through software configuration. Furthermore, no more external installations are required.
However, at the moment ERTMS Level 3 remains unproven technology on the track, and there are still a number of problems to overcome. That is why ProRail, together with Network Rail, SNCF, Arcadis and various ERTMS providers, are looking into the possibilities of adopting a ‘hybrid ERTMS level 3’ version. “With this, within ERTMS Level 3 the proven functionalities of Level 2 for trains that do not have train integrity are employed, meaning the model for the trains has approximately the same characteristics as Level 2. So this concept elaborates on the Level 2 systems. The investments in the preparation of Level 2 therefore respond well to and are largely necessary for the realisation of Hybrid Level 3”, according to Van der Vliet.
In the Netherlands, Level 2 of the ERTMS has been implemented on the Betuweroute, the Hanzelijn, the HSL-Zuid and the Amsterdam-Utrecht section. On these lines, trackside signals are no longer required. Using detection equipment connected to the rails, the ‘embankment’ monitors where the trains are. However, this equipment needs a lot of cabling, making it an expensive and maintenance-intensive solution. With Level 3, the trackside detection and the cables are not used. Trains report their own position and length using the rail communication system GSM-R.
As far back as 2013, ProRail noted that as soon as the operational model for ERTMS Level 2 was available, only small adjustments would be required to use the hybrid Level 3 version. This makes it possible to reduce trackside detection. Van der Vliet: “ProRail, Alstom, Arcadis and Bombardier carried out tests on the section of track between Lelystad and Almere. We looked if we could get the Hybrid Level 3 to work.”
“The results show that the step from Level 2 to 3 is not so big, but it is complicated. The biggest difference is the TIM [Train Integrity Monitor]. In the hybrid version, we can make a distinction between trains with integrity and those without. We can deal with them at the same time. Trackside train detection is therefore used as a fallback option if there is an interruption to or disappearance of train integrity or communication between train and embankment.”
High demands on the train fleet
ProRail ERTMS System expert Maarten Bartholomeus explains why implementation of the full ERTMS Level 3 version is not simple: “ERTMS Level 3 makes high demands on the train fleet. All trains need to have active train integrity supervision. That is difficult to achieve for goods trains and locomotive-hauled trains. There are also high demands on the transportation process. Trains have to stay standing still without communication. And the traffic managers are ‘blind’ to the trains moving without communication. Therefore the preferred solution selected is proven technology with Level 2.”
“Level 3 is possible if we use a fallback system. In the Netherlands we already have a trackside detection system we can fall back on. In practice, this means that we have two ways of reporting a position. We can free up the infrastructure on the basis of the ERTMS position report, and if this is missing or fails we can fill in the gaps with track information. This means we can integrate train and track information and so achieve optimal performance and availability.”
“With the hybrid ERTMS Level 3 version, it is possible to deal with trains with and without integrity. It is possible to make the blocks on the track smaller with the ‘virtual blocks’. With trains that report having integrity, a capacity increase can be achieved, as these virtual blocks are removed more quickly for the next train”, explains Bartholomeus. A block represents a track that becomes free as soon as a train leaves the line. The earlier that integrity functionality becomes available in the material and can be reported, the earlier the potential capacity gains can be realised.
In his presentation, rail safety expert Willie Notten from Ricardo Rail sketched out the history of train safety, which begun with a railway worker with a flag on the track when a train approached, to the EU plans to create a single European track safety system. Back in 1989, the EU decided to switch to one train safety system in order to make the European railway network more attractive and to reduce costs, said Notten. A few years later, the decision was made to introduce the European Rail Traffic Management System (ERTMS).
“Since its introduction in 1970, the principle operation of the current ATB system [Automatic Train Influencing] has not been changed, except for the addition of the Improved Version in 2008.” Many of the ATB systems in vehicles are still based on B relays. This is a technology in radio-based train safety systems that have been replaced by computer-controlled systems. This is why the KIVI seminar was given the jokey title ‘Elimination of Relay Technique Must be Speedy (ERTMS)’.
Notten outlined the differences between ETCS and CBTC. CBTC stands for Communication-Based Train Control, and is used in metro trains. The presentations by Bartholomeus and Van der Vliet made clear that the experiences with CBTC can be applied to the Hybrid ERTMS Level 3 version.
In the meantime, the Netherlands, in partnership with various providers and the European Railway Agency (ERA), has made big strides forward in terms of the implementation of the European system, Van der Vliet explains. “With the completion of the validation tests in the Siemens lab environment in 2016 and the alignment with other countries via the ERTMS Users Group and the ERA, we are now at the stage of operational field tests. System providers have been challenged to make tests possible in England from October. The results of these will, in dialogue with the ERTMS programme, be part of the roll-out in the Netherlands.”
Learn more about the implementation of ERTMS in Europe at the ERTMS Conference during RailTech Europe 2017 on the 28th of March. Go to the website for more information: https://www.railtech.com/railtech-2017/conference/