Australia looks to Europe for train control technology
RailCorp is considering ETCS Level 1 to improve safety and create additional capacity on the increasingly-congested network around Sydney. A trial to evaluate how ETCS can best be adapted for the Australian environment is now underway in the Blue Mountains
Louie Anagnostopoulos is a member of the RailCorp ATP Pilot Trial project team, managing the installation and commissioning of one of the track sites and the fit-out of the first trial train. He is currently the Test Captain, responsible for the management of the running of the trial train. Bob Hammer is Principal Consultant, Transport, with Bovis Lend Lease. He has managed the ATP Pilot Trial project from conception through to the commencement of trial running.
TEST RUNNING is currently underway in the Blue Mountains of New South Wales with three trial installations of ETCS Level 1. These form part of a pilot project that may lead to the installation of automatic train protection across the Sydney suburban network.
Although RailCorp has an existing mechanical train stop system, three significant accidents in recent years have highlighted the need to introduce a more advanced form of ATP. Upgrading of the signalling and train control systems will also provide additional capacity to accommodate projected growth in patronage over the next decade.
RailCorp is a vertically-integrated state-owned operator which provides passenger services in the greater Sydney metropolitan area. Its network of 2 100 route-km also reaches 168 km north to Newcastle, 155 km west to Lithgow and 153 km south to Nowra.
The population of this area is approximately 5·1 million people, of whom 10% use the train on a daily basis. This network must provide metro-type services in the inner city areas, an urban service to the outer suburbs and an inter-city service to the outlying satellite towns. Privately-operated intra-state and interstate freight trains traverse much of the network, adding to the complexity of its operation.
RailCorp runs 2 546 passenger services carrying 900 000 passengers per day between 302 stations. Patronage has increased by 6% over the last two years and is forecast to increase by 2·5% per annum, indicating a need to increase capacity significantly within the next 10 years.
The RailCorp passenger fleet consists primarily of eight-car double-deck EMUs carrying up to 1 200 passengers. The electric trains are powered by a 1·5 kV DC overhead supply, and rolling stock varies in age between brand new and 35 years old. RailCorp has a contract with Reliance Rail for the replacement of approximately 30% of its fleet over the next six years (RG 12.06 p761).
The RailCorp network is equipped with three and four-aspect colourlight signals managed through a mixture of relay and computer-based interlockings. Like the rolling stock, the signalling varies from brand new to approximately 40 years old, and there is an ongoing programme to upgrade the signalling on life expiry.
Capacity and safety benefits
RailCorp's existing train protection system consists of mechanical train stops that are fitted to 90% of the running signals. These trip the emergency train brakes if a signal is passed at danger. The infrastructure also has long signal overlaps, generally in the order of 500 m in advance of each signal. Together these systems have provided a rudimentary but effective means to mitigate the risk of passenger trains exceeding their movement authorities. However, the mechanical trip system is prone to failure, expensive to maintain, and it is not fitted to locomotive-hauled passenger and freight trains.
There have been several significant accidents over the last nine years that might have been prevented by Automatic Train Protection. One was a derailment resulting from overspeeding through a turnout, another a collision of a train that proceeded after stopping at a red signal, and the third a derailment associated with exceeding the allowable line speed. The last two of these incidents resulted in multiple fatalities.
The drivers for change within the RailCorp network are therefore a combination of safety, in terms of mitigating the risks of exceeding allowable speeds and exceeding movement authorities; capacity gains to maximise the effectiveness of the existing network; and greater efficiency in terms of both whole-life cost reduction and improvements in reliability.
Over the last four years RailCorp has reviewed various ATP systems. Following analysis of around 65 different alternatives, the studies concluded that the European Train Control System offered the best outcomes for the RailCorp network. The particular benefits that ETCS offered include:
- addressing the risks of exceeding permitted line speeds and movement authorities;
- potentially enabling an increase in line capacity, particularly if the existing long overlaps can be reduced;
- far greater reliability than the mechanical trip system;
- a well-developed and tested set of specifications (for Level 1 at least);
- 'off the shelf' availability (for Level 1) from multiple suppliers; and
- a long and relatively stable life-span as ETCS becomes the standard for ATP systems in Europe.
However, there remained a lot of concerns and questions that needed to be answered before RailCorp could consider implementation of ETCS on its network. These related mainly to the potential difficulty of installing ETCS on the infrastructure and rolling stock, and hence the final price of the installed system. The extent to which the RailCorp operating rules are compatible with ETCS was also unknown. RailCorp therefore decided in June 2006 to proceed with a pilot trial to address these questions and provide the information required to support a business case for full-scale implementation.
Following an open tender RailCorp selected three contractors to participate in the Level 1 pilot trial: InterOp - a joint venture between Bombardier and Westinghouse (Invensys); Siemens; and a consortium of Alstom and United Group Infrastructure.
The pilot trial contracts are proceeding in four phases as indicated in Fig 1.
The first phase is the Collaborative Development Period, which RailCorp considers to be fairly unique to its approach to ETCS. All contractors were required to provide a technical expert to work collaboratively with each other and with RailCorp experts as part of the Collaborative Development Group to develop the Application Rules. These are the rules that need to be in place to design, install, operate and maintain ETCS on the RailCorp network.
The Application Rules include the National Values as identified in the ETCS specifications, and other rules that are specific to the RailCorp infrastructure, rolling stock and operating environment. The collaborative aspects of the project have been particularly beneficial to RailCorp, giving the opportunity to learn from the experiences of three different contractors working across several different European ETCS projects.
The CDG process helped to assure RailCorp that the Application Rules are robust and provide a platform for implementation that should suit all the suppliers.
The items that were developed collaboratively include:
- the programme for the pilot trial;
- the Application Rules needed to run the trial;
- the Test & Evaluation Plan that sets out the requirements for the Test & Commissioning Plan, developed independently by each contractor; and
- the Evaluation Plan, which is the detailed roadmap for running the trial trains.
The CDG is currently completing the Application Rules needed for future implementation, and will produce a final report on the completion of the trial.
Each of the contractors has been allocated approximately 15 km of double track on the Blue Mountains line west of Sydney. Lineside equipment installation commenced in August and was commissioned in early November.
One advantage of having multiple contractors has been the opportunity to trial various alternatives in components and installation methods. For example, one of the contractors is using a current-sensing interface between the signalling system and the LEU whilst the other two are using voltage-free contacts.
Each of the contractors has also been allocated one four-car V-set inter-city EMU to install its equipment in both driving cabs of that train. During the trial, the trains are not carrying passengers and are being run to a special timetable between trains in revenue service. Because of the high service demand for the rolling stock, the project is limited to trialling one train at a time.
Siemens commenced installation on its train on September 10 2007 and completed its dynamic commissioning on November 9. This was followed by five weeks of intensive testing of the train over all three test sites in accordance with the Evaluation Plan. The InterOp train was fitted out in December and is being trialled for five weeks in January and February 2008. This will be followed by a five-week trial of the Alstom train in March and April.
The contracts will be complete by April 30 2008, following which the RailCorp team will compile a project report. The plan for ETCS implementation and a detailed business case to support the plan are due to be completed by mid-2008.
The trial has deliberately been limited in scope and time to address the major issues required to provide meaningful results, in order to move on to the implementation phase as soon as practicable. The objectives of the trial are to:
- identify the key issues for implementation;
- confirm that the contractors' systems are interoperable and suitable for implementation on the RailCorp network;
- create a competitive market by having multiple suppliers able to participate in future tenders;
- confirm that RailCorp has a viable implementation plan; and
- provide some of the information required to finalise the business case.
The issue of 'interoperability' is an interesting one for RailCorp. Although trains in Australia do not have to cross land-based national borders, some trains do travel across different state and federally-owned rail networks, and an interoperable automatic train protection system would have significant benefits.
However the main benefit to RailCorp from interoperability is not between the different state and federal rail networks but between ETCS suppliers.
Hence, for example, as a result of a tender process the first fleet of trains may be fitted with equipment from Supplier A and run on an infrastructure sector fitted with equipment from Supplier B. When the next infrastructure sector is fitted, the contract may be won by Supplier C, and the contract for the next fleet of trains won by Supplier D, thus maintaining a competitive market at all times.
It is important to note in this regard that the pilot trial is not intended to be a process to select a preferred bidder for future implementation. The best outcome for RailCorp will be to have all three contractors successfully demonstrate that their systems are suitable for implementation.
The ETCS Pilot Trial project is being run in accordance with the RailCorp Safety Management System. A Safety Assurance Report has been prepared to provide a detailed description of how safety is being managed through the design, installation, commissioning, trialling and decommissioning phases. This report identifies the safety responsibilities of the contractors, the RailCorp project team and the RailCorp design authorities.
One of the major decisions made early in the project was that the trial trains would be run fully in accordance with RailCorp's existing safe-working rules. This meant that the ETCS equipment was not required to provide the primary means of safety during the trial, and the contractors did not need to certify their systems to SIL 4, saving a significant amount of time and cost.
Because of the risk that the driver would be distracted from the driving task whilst also watching the ETCS Driver Machine Interface, the trial trains operate with a second driver in the cab with the prime responsibility of watching the track ahead and the lineside signals.
Although the trials will not be complete until mid-2008, the project has already identified some preliminary outcomes of interest. Initial trial running has confirmed a successful level of interoperability with the three contractors' trackside systems.
The trackside system installation and commissioning was not as difficult as first envisaged, but the need to provide accurate track data to the contractors (such as distances, gradients and speed profiles) beforehand is clearly essential.
As yet there is no definitive specification for the DMIs. The three test installations all vary in content and display format. This has highlighted that the configurable features of the DMI (for example, dynamic colour changes during speed monitoring) need to be defined early in the design phase.
Equally, the margins for monitoring of excess speed, through warnings and brake intervention parameters, need to be clearly defined and included in the driver training programme.
Clearly, with the project still ongoing, there are several areas where more research is required. There is no agreement on the application of braking curves in the design of ETCS, and the choice of braking curve to meet safety and operational objectives will require more development.
One emerging concern centres on the lack of space and the interfaces for brakes and electrical equipment which makes fitting ETCS to older trains more difficult.
Nevertheless, the pilot trial is a significant milestone in the provision of automatic train protection on the RailCorp network. It heralds the beginning of a new phase of railway development, not only for RailCorp but for the whole industry in Australia.
- CAPTION: RailCorp staff join representatives from the signalling consortia at Penrith station ahead of the departure of the first train to use all three test sites over the 15 km stretch of line in the Blue Mountains.
- CAPTION: Balises installed at the InterOp consortium's test site
- CAPTION: Alstom engineers commission a balise
- CAPTION: Fig 1. A business case paving the way for ETCS implementation could be in place by the second half of the year
- CAPTION: The initial stages of the Blue Mountains trial have indicated that installation of ETCS lineside equipment and track balises in an Australian environment is more straightforward than had been expected. This is an LEU and Euroloop modem supplied by Siemens for its test site
- CAPTION: Each supplier has fitted Driver Machine Interfaces that give slightly differing display formats. This is the Siemens device fitted, temporarily, to the first test train