Railway Interlocking System and Method

Abstract

A computer generates European Train Control System (ETCS) interlocking data based on conventional control signals in an existing railway network. First, an ETCS data tooling 24 receives geographic con

Description

The present invention relates to a railway interlocking system for existing trackside infrastructure in a railway network, comprising conventional interlocking and ETCS level 2 interlocking, and a computer-implemented method of generating an ETCS interlocking based on conventional railway control signals in an existing railway network. The introduction of European Train Control System (ECTS) to the railway is central to the ability to provide low-cost operation, highly competitive railway networks. There are five levels of ETCS, each requiring differing amounts of changes to trackside equipment and / or locomotives or driving cars. These levels are: • Level 0: ETCS-compliant locomotives or rolling stock do not interact with ETCS trackside equipment; • Level NTC: ETCS-compliant locomotives are equipped with additional Specific Transmission Modules (STM) for interaction with legacy signalling systems, and cabs are provided with standard ETCS driver interfaces; • Level 1: ETCS is installed on trackside equipment and on board a locomotive, and spot transmission of data from track to train and vice versa occurs via balises; • Level 2: As level 1, but the balises are used for exact train position detection only, and continuous data transmission via GSMOR with the Radio Block Center (RBC) give the required signalling information to the driver's display. This level can be either as an overlay on an existing system or completely without lineside signals; and • Level 3: As level 2, but train location and train integrity supervision no longer rely on trackside equipment. An example of where ETCS can provide additional safety advantages over conventional signalling systems is illustrated in Figure 1. Figure 1 is a schematic illustration of conventional junction signalling. A railway track 1 has a junction 2, the approach to which is controlled by two signals 3, 4. A first signal 3 is provided proximate the junction 2, and is used to control access to the junction 2 as well as indicate the route a train should take by means of the route indicator 5. A second signal 4 is provided a distance away from the first signal 3 and used to control entry to the section of railway track 1 situated immedi ately before the first signal 3. In the example shown, the first signal 3 is at clear (green -indicating that a train may proceed), and the second signal is at caution (yellow - indicating that the driver must prepare to stop the train at the next signal). The route indicator 5 is used to inform the driver which route is set for the train at the upcoming junction 2. Trains that turnout can be subject to quite severe speed restrictions, and without suitable mitigations there would be insufficient time to respond to a route indicator before reaching a junction 2. Consequently, a number of measures have been developed to reduce a train's speed on the approach to a critical location. These measures include: • Approach release of signals - holding a signal protecting a junction at a more restrictive aspect to slow the train down (such as a flashing yellow signal). The protecting signal changes to a less restrictive aspect after the train has been detected in the vicinity of the signal fora specified length of time. • Modified aspect sequences - additional aspects can be added to signals in rear to modify the displayed aspect sequence. Flashing yellow and double flashing yellow signals are used to warn the drive to reduce the speed of the train. If there are two turnouts after a signal an additional method is needed to indicate the approach speed. In these cases, preliminary route indicates can be added on the approach to the turn out or split distant signals cane be added. One addition problem with the use of route indicators is that they are many different types, depending on the line speed and other factors, such as the age of the railway. This means that in practice, the driver must be trained to understand the signals on the route and can only drive the handful of routes for which they have competence. Train Protection and Warning System (TPWS) loops are added at higher-risk locations to facilitate an automatic train stop in overspeed conditions, but these are not a failsafe solution as the train could in theory increase in speed after passing the loops. TPWS also increases the cost and complexity of signalling solutions. However, Automatic Train Protection (ATP) which brings the train to an automatic stop in case of danger or overspeed is present in ETCS Level 1 and above, meaning that the use of ETCS is advantageous in terms of safety. ATP is full and continuous, rather than TPWS, which is only provided at specific locations. This also means that temporary speed restrictions can be handled more easily, since the ETCS guarantees that the train will not exceed any imposed limit. ETCS also provides continuous cab signalling to a driver. On a railway with fixed signals the driver will only receive information at fixed points where the train passes a signal. It is not possible to take advantage of the train ahead moving away, or an unseen signal ahead now displaying a less restrictive aspect. It is also possible to modify traffic flow patterns and routes using ETCS in a manner that is not possible using conventional signals. By avoiding the use of conventional signals it is also possible to reduce the amount of trackside equipment required, such as trackside signals, signal power supplies and signal controllers. Trackside point operating equipment and train detection system components will still be required, however, but by reducing the amount of infrastructure, and more specifically, the amount of concrete needed to mount and secure such infrastructure alongside the railway track is also reduced. This leads to a beneficial effect on the carbon footprint of ETCS compared to that for conventional signalling. However, the installation of ETCS systems is both a resource-intensive and technically challenging undertaking. The process is further complicated when upgrading an existing area under the control of conventional lineside signals in non-ECTS operation. Data production tools and expertise are often aimed at supporting these conventionally-signalled areas, and therefore need to be adapted to support ETCS components. The inclusion of a Radio Block Center (RBC) to the system architecture in ETCS levels 2 and 3 adds an additional component that must be supported and tested. Furthermore, in ETCS level 2 and higher, the system can be configured in a "no signals" variant, in which traditional lineside signals are not present. This causes a significant deviation in the manner in which components, such as the interlocking, must consider and control the railway network. There is usually a significant amount of work required as the existing trackside system is incompatible with the new ETCS system. The de-facto approach to this is to renew the entirety of the existing system to allow a smooth transition to the ETCS system. In effect, two new systems must be provided to enable the final one. Deployment strategies for ETCS systems depend on several factors, primarily whether it is an upgrade to an existing area of the railway network under conventional control or a new development. One situation where an upgrade may be required is where existing trackside infrastructure is to be updated to ETCS Level 2 or 3 architecture in a "no signals" configuration. In this scenario, the system will have the traditional line side signals that are controlled by the convention interlocking replaced by uncontrolled block markers denoting a position on the railway network. Control functions are then handled between the RBC and an ETCS interlocking. The upgrade process will require a modification of trackside infrastructure, such as the installation of non-controlled balises along the trackside, which are essential for enabling ETCS operation. For example, transparent data balises, which are transponders placed between the rails of a railway acting a s beacon giving the location of a train and transmitting signalling information to a train, and fixed balises, which are programmed for specific information such as speed limits and gradients will need to be installed. It is not often feasible to carry out these modifications to the trackside in a single state as this would render the railway non-operational for a significant period of time. Instead, such works are usually scheduled in stages to handle more limited areas while limiting the impact on the availability of the railway. Many of the existing issues are caused by the geographically distributed architecture of the signalling system. With many thousands of interfaces required between the trackside equipment and the interlocking, the point of interface between old and new systems is always at the trackside. This presents a volume problem in creating thousands of temporary trackside interface connections, but avoids the need for a high integrity and challengingly complicated single interface at interlocking level. The present invention aims to address these issues by providing, a computer-implemented method of generating ETCS interlocking data based on conventional railway control signals in an existing railway network, comprising: receiving geographic configuration data at an ETCS data tooling; extending the geographic configuration data by applying ETCS signalling design to generate ETCS configuration data; passing the ETCS configuration data to an interlocking generator; generating ETCS interlocking data at the interlocking generator by combining the ECTS configuration data with an existing trackside interface definition received from conventional interlocking; and outputting the ETCS interlocking data to an ETCS interlocking. Preferably, the method further comprising the steps of: passing the ETCS configuration data to an RBC compiler; compiling RBC data based on the ETCS configuration data; and outputting the compiled RBC data to an ETCS RBC. Preferably, the step of applying ETCS signalling design to the geographic configuration data comprises replacing signals with block markers and determining balise locations. Preferably, the geographic configuration data comprises a topographical map of the existing railway network. The invention will now be described by way of example only, and with reference to the accompanying drawings, in which: Figure 1 is a schematic illustration of conventional junction signalling; Figure 2 is a schematic illustration of a railway interlocking system for existing trackside infrastructure in a railway network in accordance with embodiments of the present invention; Figure 3 is a flowchart illustrating the steps in a computer-implemented method of generating an ETCS interlocking based on conventional railway control signals in an existing railway network in accordance with embodiments of the present invention; Figure 4 is a schematic illustration of a test-rig for demonstrating embodiments of the present invention; and Figure 5 is a schematic diagram of an ETCS upgrade using the embodiments of the present invention. Embodiments of the present invention offer a solution to the above issues of ETCS installation by avoiding the use of overlay systems and without needing to renew the trackside infrastructure. The process converts an existing railway signalling system comprising an existing conventional interlocking with an existing conventional trackside signalling system and lineside signals to a signal-less ETCS level 2 system comprising an ETCS level 2 interlocking, whilst retaining the existing trackside system. The new ETCS level 2 system is generated using the existing system as the input. In conventional trackside infrastructure signals are used to indicate whether or not a train can proceed, whereas in ETCS a movement authority is transmitted via the balises. Consequently, in embodiments of the present invention there is no requirement to reconcile two different proceed-authority control layers. The railway interlocking system for existing trackside infrastructure in a railway network comprises conventional interlocking, ETCS interlocking and a railway interlocking data processing system. The railway interlocking data processing system forms a common interface between the ETCS interlocking and the conventional interlocking. It is adapted to generate a like-for-like ETCS interlocking from the conventional interlocking. The railway interlocking system is further adapted to be switched between the conventional interlocking and the ETCS interlocking alongside the existing trackside infrastructure. To enable the railway interlocking data system to work a computer-implemented method of generating an ETCS interlocking based on conventional railway control signals in an existing railway network is used. In a first step, geographic configuration data is received at an ETCS data tooling. Next, this geographic configuration data is extended by applying ETCS signalling design to generate ETCS configuration data. The ETCS configuration data is passed to an interlocking generator, which generates ETCS interlocking data by combining the ECTS configuration data with an existing trackside interface definition received from conventional interlocking. This ETCS interlocking data is then to an ETCS interlocking. Embodiments of both the system and method will now be described in more detail below. Figure 2 is a schematic illustration of a railway interlocking system for existing trackside infrastructure in a railway network in accordance with embodiments of the present invention. The railway interlocking system 20 comprises conventional interlocking 21 under conventional control (trackside signals) and ETCS interlocking (ETCS level 2 / 3) 22. The ETCS interlocking is under a no signals condition, such that signal control logic is absent and the interlocking is simplified. A railway interlocking data processing system 23, illustrated within the bounds of the broken-line box, forms a common interface between the ETCS interlocking 22 and the conventional interlocking 21, and is adapted to generate a like-for-like ETCS interlocking from the conventional interlocking, such that the ETCS interlocking is functionally equivalent to the conventional interlocking. Additional functionality may be provided, but must be within the constraints of the existing trackside architecture. In this manner embodiments of the present invention reuse existing assets to deploy ETCS systems. The railway interlocking data processing system 23 comprises ETCS data tooling 24. This is adapted to receive geographical configuration data 25 in the form of a topographical map of the railway network and to extend the geographical configuration data 25 by applying an ETCS signalling design to generate ETCS configuration data 26. The ETCS signalling design comprises block marker conversions of signals in the railway network and balise locations. The railway interlocking data processing system 23 also comprises an interlocking generator 27 adapted to receive the ETCS configuration data from the ETCS data tooling 24. The interlocking generator 27 generates ETCS interlocking data by combining the ETCS configuration data 26 with an existing trackside interface definition received from the conventional interlocking 21. The ETCS interlocking data is then output to the ETCS interlocking 22. In addition, the railway interlocking data processing system 23 is provided with an RBC data compiler 28, that is also adapted to receive the ETCS configuration data 26 from the ETCS data tooling 24. The RBC data compiler 28 generates compiled RBC data based on the ETCS configuration data 26 that is then output to an ETCS RBC 29. The ETCS interlocking 22 is adapted to communicate with both the ETCS RBC 29 and existing trackside infrastructure 30. This is due to the use of the existing geographic configuration data 25 and trackside interface definition of the conventional interlocking 21. The ETCS configuration data 26 also includes ETCS configuration decisions 31. The railway interlocking data processing system 23 is therefore able to produce an ETCS RBC 29 and an ETCS interlocking 22 that controls the area covered by the conventional interlocking 21. The railway interlocking data processing system 23 provides an interface that is able to automatically generate the required data for ETCS RBC and ETCS interlocking from existing data and therefore reduces the amount of human interaction required in design decisions regarding ECTS operation, such as deciding ETCS levels and permitted behaviours. The generated ETCS components may be installed easily alongside existing conventional trackside infrastructure without adversely affecting its operation, and without requiring modifications to signal control logic, which would require extensive testing. The ETCS interlocking 22 and the ETCS RBC 29 are therefore provided in addition to the existing conventional interlocking 21 in order to utilise the generated ETCS components. Using a single source of data (the geographic configuration data) to generate all location-specific data automatically, including the data for the ETCS interlocking and the ETCS RBC simplifies adding functionality to the system. For example, it is possible to include bi-direction operation in areas where this has not been possible previously. A digital twin of the signalling system is also produced from the single source of data, and deployed in a cloud environment for testing and demonstration purposes, as described with reference to Figure 4 below. The digital twin is constructed using the automatically generated data with simulators that utilise this data. Figure 3 is a flowchart illustrating the steps in a computer-implemented method of generating an ETCS interlocking based on conventional railway control signals in an existing railway network in accordance with embodiments of the present invention. The method 400 begins, at step 302, by receiving geographic configuration data 25 at the ETCS data tooling 24. The geographic configuration data is then extended by the ETCS data tooling 24 by applying ETCS signalling design to generate ETCS configuration data 26 at step 304. As described above, this involves the replacement of signals with block markers and the determination of balise locations into the geographic configuration data. At step 306, the ETCS data tooling 24 passes the ETCS configuration data 26 to the interlocking generator 27, where, at step 308, ETCS interlocking data is generated by combining the ECTS configuration data 26 with an existing trackside interface definition received from the conventional interlocking 22. Then, at step 310, the ETCS interlocking data is output to the ETCS interlocking 23. As outlined above, the railway interlocking data processing system 23 also includes an RBC data compiler 28. At step 306 the ETCS data tooling 24 also passes the ETCS configuration data 26 to the RBC data compiler, which at step 312 compiles RBC data based on the ETCS configuration data 26 and at step 314 outputs this compiled RBC data to the ETCS RBC 29. In order to test embodiments of the present invention a test rig was created from existing product hardware and a shared trackside and train simulation. Figure 4 is a schematic illustration of a test-rig for demonstrating embodiments of the present invention. The rig 40 has a shared trackside and train simulator 41 hosted on a first computing device 42, which can be connected to one of two signalling systems. The conventional signalling system 43, comprises a conventional interlocking 44, in this example, a Siemens Trackguard Westlock™ interlocking, and a second computing device 45, linked to the conventional signalling system 43 via a communications network 46. The second computing device 45 hosts both a control system simulator 47 to control the conventional interlocking 44 and a conventional-side trackside interface simulator 48, with the conventional interlocking 44 connecting to the conventional-side trackside interface simulator48 in order to provide interlocking data. The ETCS signalling system 49 comprises a third com puting device 50, an ETCS RBC 51 and an ETCS interlocking 52. In this example, a Siemens Trackguard Futur RBC and a Siemens Trackguard Westrace™ Mk2 interlocking are used as the ETCS RBC 51 and the ETCS interlocking 52, respectively. The third computing device 50 runs a Siemens Controlguide WESTCAD™ control system 53 and an ETCS-side trackside interface simulator 54. Each of the trackside simulators 41,48, 54 are based on a Westrace™ Trackside System (WTS) in use on the railway in the United Kingdom, and use a common set of geographic configuration data as described above. Both the conventional signalling system 41 and the ETCS signalling system 49 have an ethernet network and are connected to the shared trackside and train simulator 41 via a shared ethernet switch 55. The shared ethernet switch 55 can be configured to switch between the conventional signalling system 41 and the ETCS signalling system 42. The following simulations were carried out: 1. driving a simulated train into the ETCS area under the conventional signalling system 41; 2. changing the signalling system over from the conventional signalling system 41 to the ETCS signalling system 42 using the shared ethernet switch 55 whilst the train is stationary; and 3. registering the train with the ETCS RBC 51 and driving it through the new signalling area under the control of the ETCS signalling system 42. This demonstrated successfully that it was possible to switch between the conventional signalling system 41 and the ETCS signalling system 42 based on using embodiments of the present invention. The Westlock™, Westrace™ and WESTCAD™ systems are available in the United Kingdom from Siemens Mobility Limited (www, m o b 11 i W- sie m e ns.com). However, the method is also suitable for use with other forms of interlocking, and not limited to use with the Westlock™, Westrace™ and WESTCAD™ system. The approach of the embodiments of the present invention reduces the effort and cost to deploy an ETCS system through the reuse of existing railway infrastructure and assets. By reducing the complexity of the interlocking logic and utilising data automation the extent of human effort involved in the design and data preparation stages of an ETCS implementation is also reduced. The approach is applicable to a wide range of interlock ing technologies but particularly suited where interface definitions and geographic data is available in a machine-readable format, since this also reduces the amount of human effort required in data production. The embodiments of the present invention provide a method to upgrade conventional operation to ETCS operation under a no signals configuration that can be implemented in a first stage by relying on the operation of existing conventional equipment. In traditional approaches, this existing conventional equipment is rendered inactive by the introduction of an overlay or similar system that aims to completely replace the existing conventional equipment immediately. The single-stage upgrade of the embodiments of the present invention allows ETCS-capable interlocking logic to be simplified, and therefore facilitates the greater use of data automation in the development process. By producing tools that reuse the existing trackside definitions, the embodiments of the present invention are able to automatically configure an ETCS interlocking that can communicate with the existing railway infrastructure, and so reduce the effort required to carry out an ETCS upgrade. The combined effect of the embodiments of the present invention is to provide a cost saving over the traditional overlay approach, and therefore increases the appeal of ETCS to railway operators. In addition, the ability to switch between ETCS and non-ETCS operation using conventional equipment permits an upgrade approach that can rely on the well-understood and thoroughly tested conventional equipment, whilst testing activities and training are carried out only on the newer ETCS components. Figure 5 is a schematic diagram of an ETCS upgrade using the embodiments of the present invention. This example is split between actions taking place in an operating centre 56 and actions taking place at trackside 57. A track layout diagram 58 illustrates the physical changes taking place as a result of these actions. At the operating centre 56, the interlocking processor 59 for the conventional interlocking remains in place during the upgrade, and is recovered following the final commissioning of the new ETCS signalling system 60. The railway interlocking data processing system 23 described above is used to generate the data required for the ETCS interlocking 61 (for ETCS level 2 no signals, TPWS or Advanced Warning System (AWS) are required) and the ETCS RBC 62. This facilitates incremental improvements following commissioning. Both the conventional interlocking processor 59 and the new ETCS signalling system 60 are linked to a changeover switch 63 by an ethernet network 64. This may either be recovered after commissioning, or retained to allow mixed mode operation, such as ETCS operation during the daytime when the railway network is busy with passenger trains, and conventional operation at nighttime when freight trains are using the railway network. This also removes the need to upgrade all rolling stock immediately. The changeover switch 63 is connected to an intelligent interface 65 that enables communication between the operating centre 56 and the equipment at the trackside 57. The equipment at the trackside 57 includes a number of object controllers 66a - d, that control equipment such as signals, axle counters, track circuits and points. Of these, those controlling points will be retained after commissioning, and those controlling signals will be recovered. Over time, track circuits may be replaced with axle counters, but points controllers will be retained permanently. The track layout diagram 58 shows the addition of balises 67a - h, and indicates signals 68a - h that will be recovered after commissioning. By removing the signals 68a - h the need to control trains on the railway network based on train braking distances is removed, thus enabling the existing railway infrastructure to support services that would not have been possible under the conventional signalling regime.

Claims

1. A computer-implemented method of generating ETCS interlocking data based on conventional railway control signals in an existing railway network, comprising:receiving geographic configuration data as an input to ETCS data tooling;extending the geographic configuration data by applying ETCS signalling design to generate ETCS configuration data;passing the ETCS configuration data to an interlocking generator;generating ETCS interlocking data at the interlocking generator by combining the ECTS configuration data with an existing trackside interface definition received from conventional interlocking; andoutputting the ETCS interlocking data to an ETCS interlocking.

2. A computer-implemented method as claimed in claim 1, further comprising the steps of:passing the ETCS configuration data to an RBC compiler;compiling RBC data based on the ETCS configuration data; andoutputting the compiled RBC data to an ETCS RBC.

3. A computer-implemented method as claimed in claim 1 or 2, wherein the step of applying ETCS signalling design to the geographic configuration data comprises replacing signals with block markers and determining balise locations.

4. A computer-implemented method as claimed in claim 1, 2 or 3, wherein the geographic configuration data comprises a topographical map of the existing railway network.

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