Next-generation control systems

The last twelve months have seen a number of notable developments to Siemens Rail Automation’s control systems technology, with significant improvements in the functionality, performance and configuration of the key systems components.

At the heart of the company’s suite of products is its proven Controlguide Westcad computer-based control and display system, which following the development of new Modular Control Rack (MCR) technology, is now able to incorporate train describer functionality and to interface seamlessly with the Controlguide Westronic 1024 Time Division Multiplexer (TDM) system.

Controlling the Loop

The first application of this new technology was deployed in 2012 to support Network Rail’s European Train Control System (ETCS) trials programme at its National Integration Facility. The work covered a five-mile stretch of the down line on the Hertford Loop (between Molewood Tunnel and Langley South junction) which now has the interlocking control from a relocatable equipment building (REB) in the former Hitchin goods yard.

Siemens designed, installed, tested and commissioned an MCR system in the REB to provide a local control point for the interlocking – the remote/main control work station being at Kings Cross Power Signal Box, with Hitchin being the local facility. A lockable switch at Hitchin allows for the transfer of control between the emergency Westcad at Hitchin and the main Westcad control work station at King’s Cross.

The project represented the first installation in the UK of a computer-based interlocking being controlled remotely over Network Rail’s Fixed Telecoms Network (FTN), effectively proving the ability of Westcad MCR to remotely control any interlocking anywhere in the UK over the FTN. To provide a higher level of protection than would be given by the FTN, a new proprietary communication protocol was introduced.

Bigger performance, smaller package

Having received Generic Approval from Network Rail and having been through a full safety case, Controlguide Westcad MCR and Westronic 1024 both incorporate Siemens’ new mid-plane technology, providing the smallest possible footprint and dramatically reducing the size of standard control systems equipment (reducing the space requirement for a complete control system from a full equipment cubicle to the size of a standard domestic microwave oven). The introduction of common modules also allows for standardisation in both training and spare-holding requirements, with the modules all fully EMC-certified for installation within their own housing, or for mounting in relay racking, 19 inch cubicles or at the rear of a work-station.

Due to be commissioned later this year, the Wolverhampton resignalling programme will be the first to feature a fully-duplicated control and train describer system in a single rack, both running on the same processor and with a direct interface for the required emergency alarms.

Mike Lewis, Siemens Rail Automation UK’s head of control systems, said: “This project will represent the most cost-effective control centre solution available, with the train describer running as a software module within our proven control system to deliver significantly improved performance and reduced cost, and perfectly demonstrates the dramatic reduction in required footprint – from a full cubicle to a single rack.

“Unlike other manufacturers, we took the decision at an early stage in the development process to base our system developments on bespoke hardware, rather than relying on commercial, off-the-shelf (COTS) solutions. This not only allowed us to specify equipment without having to make compromises, but also to keep full control of the hardware development and manage the whole life cycle of the product, with the design of the connectors and interfaces ensuring full backward and forward compatibility.”

A major requirement of the development programme was to ensure a familiar user interface for the systems as well as providing the flexibility for their use in a wide variety of new and retrofit applications.

Mike Lewis continued: “With this dramatic reduction in size comes some obvious benefits. The unit is more portable and features much simplified cabling and drawings; consequently design, installation and testing are all easier and significantly faster. With a range of diagnostic tools and hot-swap standby features, the system is also incredibly reliable and easy to maintain.

“The move away from industrial PCs and Compact PCI technology allows any of the cards to be hot-swapped. Consequently, the system can ‘lose’ a card and it automatically switches to another whilst the faulty one is repaired and replaced. We’re using a ten layer mid-plane to do all the interconnections, which has eliminated the need for multiple processor housings and the associated interconnects.”

Faster installation

Using a suitable communications link, the system is able to drive most types of interlocking, including solid- state interlocking (SSI), Trackguard Westlock, Trackguard Westrace and relay interlockings. Automatic Route Setting (ARS) and Automatic Route Facility (ARF) have also both been successfully integrated and are operating on Network Rail infrastructure.

Earlier this year and as part of the Thameslink programme at London Bridge, Siemens undertook a full, like-for-like replacement of the life-expired train describer equipment. The company introduced a modern system designed and developed to provide support both for the legacy equipment and future upgrade requirements, including the facility to allow simple re-control to Three Bridges rail operating centre (ROC).

By employing the new technology as front-end signalling processors, the company was able to complete a seamless changeover, with implementation having to be undertaken to minimise possession times, access times and operational disruption. The new train describer cubicles were all installed in their final position with all the new interfacing cabling and trunking pre- installed. Whereas the original equipment was installed in the 1990s over a whole weekend, this work was commissioned in less than half that time.

Another first for the application of this new technology was introduced as part of the Huyton to Roby resignalling programme which was commissioned in July 2014. Developing a bespoke signallers’ workstation, Siemens configured its Controlguide Westcad MCR system as a front-end display solution, with an ethernet connection to the equipment room interlocking management system (IMS). This custom desk incorporates ‘slide-out’ equipment bays to maximise the maintainability of the equipment and has been so successful, that Siemens has received orders to install the same solution for York, Rugby and Three Bridges ROCs.

Flexible functionality

Completing the control systems portfolio is Siemens’ Controlguide Westronic 1024 system which includes a point-to-point TDM, panel processor, emergency alarm system, signalling SCADA RTU and panel and TD input multiplexers. Again flexibility has been key to the system’s development and it can accept a number of rear transition cards, allowing for the simple ‘plug and play’ replacement of existing TDM systems such as S2 and TDM69.

The system is able to be used as part of re-control projects where existing route relay interlockings are retained – the rear cards of the product are simply changed to suit the site, rather than an extensive programme of rewiring being required. Changeover times are therefore significantly reduced and route closures minimised.

Fully compliant with Network Rail’s FTN, the systems are also capable of interfacing to all types of interlocking (including BR Freewire, geographical, Western E10K, ERSE and OCS). The complementary output card (COP) also guards against single-bit failure of TDMs and allows a direct connection to ERSE and E10K interlockings, significantly reducing the need for additional relay circuitry for these two interlockings on re-control schemes.

Mike Lewis continued: “We have now pre-installed 12 Controlguide Westcad MCR systems in the Manchester ROC this year, and have also secured the control systems work for both the York ROC Stafford resignalling programme (which is the first to be commissioned into Rugby ROC).

“With further work at the East and West Midlands control centres during the year, we will also be installing two further systems at Three Bridges ROC over Christmas 2014 as part of the wider Thameslink programme. Future phases will introduce our Westcad E software which has interfaces to the Siemens radio block controller (RBC) for ERTMS applications.

“We are however also continuing with the development of the systems group of products, with Immediate Route Setting (IRS) functionality planned to be introduced in 2015 at Cardiff and Romford ROCs as part of our ongoing Traffic Management Systems work with Thales. This will provide a direct interface between our Westcad MCR control system and Thales’ Aramis traffic management system and introduce our Controlguide Westcad technology which allows for flexible control.

“Future development work will also see the development of interfaces to the Controlguide Westcad E system from Frequentis’ telecommunications system and a novel solution to interface CCTV level crossing control – all of which will allow even greater flexibility of working between desks”.

William Wilson, Siemens Rail Automation’s director sales and commercial, said: “These are very exciting times for Siemens; having made a significant investment in new technology, we now have a portfolio of products ready for the next generation of Network Rail projects which require operational cost efficiencies, higher reliability, functionality and performance.”