How our Overhead Line Monitoring Systems help support homologation and keep networks operational

Martin Loibl, Marketing Manager, DB Systemtechnik explains the benefits of the technology and the approach developed and deployed, both for Deutsche Bahn and other Networks:

ENSURING SYSTEM PERFORMACE IS KEY

Delivery of energy to rolling stock through high-voltage overhead lines is the predominant distribution method used on many of the world’s railways.  Indeed, this has become the primary choice, particularly on high speed – high profile routes.  Ensuring consistent contact at the interface between the pantograph on the train and the overhead line infrastructure is of fundamental importance to almost every aspect of operation. If this contact is broken, so is the energy supply, which can have a major impact on operations.

To ensure a reliable energy supply, where the carbon strips are in constant contact with the overhead wire, it is important that the pantograph and overhead line specifications are appropriately matched.  Furthermore, ensuring that the equipment performs as specified, day in – day out, is of fundamental importance, this will help to ensure smooth and safe running, minimising the costly delays of overhead line (OHL) failures.

HOW TO ENSURE THAT THE SYSTEM PERFORMS AS DESIGNED?

Determining conformance with the design requirements is the first stage of ensuring continuing correct system performance.

The initial stage is to perform a simulation of the whole system – train and infrastructure according to the European standard EN50318 for simulations of the dynamic interaction between pantograph and overhead line.  Such a simulation will provide confidence that the current collection system will perform as designed.  At this stage it is also possible to determine the worst case vehicle configuration.  Normally, for multiple units, this usually happens to be when units have been coupled together, resulting in two pantographs being in close proximity.  It is possible to define a homologation test strategy for the system and the expected vehicle configuration.

SO WHAT IS ACTUALLY INVOLVED IN PANTOGRAPH HOMOLOGATION TESTING?

Firstly, the test pantograph needs to be suitably instrumented and its ‘measurement system’ calibrated according the European standard EN50317.  We do this in our laboratory in Munich, which houses our calibrated test rig.

During homologation testing, according to the requirements of TSI ENE, TSI Loc&PAS and the European standard EN50367, our on-board engineers monitor the interaction of the pantograph with the overhead line.  This testing normally starts with our test engineers being located at a test track in mainland Europe, followed by specific route testing in the country concerned. We are experienced in undertaking such testing for and in the UK. For example, we have been supporting Hitachi Rail Europe with the testing and commission of their new trains for the Intercity Express programme and this has involved pantograph and OHL testing.

To summarise, we monitor the contact forces, accelerations and catenary uplift for contact loss, hard spots, height and stagger.   We are also able to measure optical wire geometry and wear, this provides the additional benefit of contact wire wear.  It is normal to include a speed and location system to ensure that the location of the captured data is accurately recorded.

Our engineers monitor the interaction between the pantograph and overhead line. As part of the testing, they also determine the contact forces between the pantograph and overhead line, as well as the aerodynamic performance in each direction of travel and the directional flow.

CAN YOUR EQUIPMENT BE USED ON IN-SERVICE PASSENGER STOCK?

Yes it can.  Effectively there is little difference.  We utilise the same technologies and deploy them in a very similar manner, albeit the equipment is capable of unattended operation without the requirement for operator intervention.

This provides a wealth of monitoring data on a daily basis simply as a consequence of passenger operations.  Collected data is transmitted off-board for data interrogation and analysis purposes.

Occasionally we are asked to also deploy our video image capture and analytics capability.  This involves the addition of high resolution cameras and a lighting system to enable the system to operate in poor light conditions and at night time.  The additional benefit here is that the operator gets to make use of our analytics software that provides additional data and analysis.  This is also capable of identifying infrastructure anomalies.

WHY IS CONTINUOUS MEASUREMENT OF THE OHL INTERFACE IMPORTANT?

Knowing who to blame is often cited as a reason to monitor this interface and whilst in the UK this can be helpful, it is important not to forget where the true benefits lie, namely the early detection of vulnerabilities in the catenary system, providing warnings of impending infrastructure failures. This leads to:

• Less incidents, leading to improved safety
• Avoidance of costly & time consuming repairs (infrastructure & train)
• Improved passenger services & confidence

One of the most important benefits that is often overlooked is the ability to ‘learn’ from such events by understanding the root cause of incidents.  Knowing this is essential to the elimination of future / repeat failures of the same type.

HOW CAN WE HELP?

ESG Rail is the route to market for the DB Systemtechnik and DB Engineering & Consulting product and service portfolios in the UK.  We can rapidly deploy existing and proven solutions on to the UK rail network, enabling values to be realised earlier in the project lifecycle.

TALK TO THE EXPERTS

To understand how DB’s overhead line monitoring systems can benefit you here in the UK, contact us directly via heidi.lee@dbesg.com.