Written by Grahame Taylor
Right place, right time
Last month, the rail engineer carried the first part of Grahame Taylor’s interview with Peter Dearman, Network Rail’s Head of Network Electrification.
Peter looked at the recently authorised Great Western electrification and its impact on civil engineering structures, permanent way and how it will interface with all the other schemes under way on that route.
In the second part of our coverage, he shares his ideas about the new technologies that are emerging in the field of overhead line electrification and how these will have a major impact on costs and the viability of future schemes.
It’s obvious that this is a subject close to a railway engineer’s heart, and the tempo of the interview picked up accordingly.
Delivering reliability
There are all sorts of things being developed at the moment. All sorts of things! For the Great Western scheme, the overhead line system will be new. It will be new for a number of reasons. One is that over the years we’ve learnt quite a lot from the equipment that we’ve got and we know some of the reliability issues that it throws up.
And it would be foolhardy to build more of the same when we know that we can improve on some of these reliability issues.
In parallel with that there are improvements in Europe which are being driven principally by interoperability, although that’s not really for us. But a spin-off will be the ability to cross-compatibly purchase traction systems and, in particular, the pantographs.
So this leads us to reassess how the dynamics of the overhead line work and therefore open up the possibility of high-speed operation (140mph) using European pattern pantographs.
Has the OLE kit evolved from European kit?
“We’re talking to people all over the world – in fact I’ve spent some time in Brussels and Paris talking to European colleagues, understanding what their systems can teach us and what we can take on board and adopt.”
The quest for high output
There’s been mention in the press of a high output factory train. What’s the current position with this?
“The term is a bit misleading. It’s more of a factory system and will include a piling train, a steel erection train and also the vehicles required to enable the OLE to be attached to the masts and the wires to be run.
“In a way it’s a compilation of all the bits of kit that used to run around separately but it’ll be a much slicker version of that – in fact our wiring vehicle (and there are versions of this in Europe so this isn’t way-out technology) will be able to run both the catenary and contact wires at tension in one run.
“That has massive implications for productivity. I anticipate that as we move forward into full production and once the guys on the train become familiar with all the kit, we should be getting two wire runs a night…at tension.
“One of the innovations we’re looking at is a non-weight tensioner – a spring tensioner. It will offer simplicity of construction and also benefits of long-term maintenance. We have some on trial and testing on the GE main line.
“But, really, the high output plant – not ‘train’ – is, in a sense, not innovative at a single unit level. All the individual items have evolved of course to quite a high level of sophistication, but in themselves they’re not new.
“However the production logistics process that we envisage using to maximise the work output during short possession windows is really innovative. It requires us to work with our suppliers and for all of us to put our thinking caps on to achieve the sorts of production rates we need to achieve on a modern railway.”
So you’re thinking of shore facilities to service it to make sure everything is ready?
“Indeed. If you think this through…two wire runs a night. That means the train has to carry four runs of cable. It has to carry 50 overhead line structure cantilever assemblies and when you go to the first stanchion position you want the first one you pull off to be at the top of the pile, not the bottom!
“Now, that sounds fairly trivial, but if you then think six shifts a week, 300 of these things in the right sequence loaded during the day to be used during the night then that’s not an engineering production process…it’s a ‘Tesco Daventry logistics’ process right the way back to the supplier.
“So we’re working with the supply chains to improve our joint ability to achieve all this. I’m really encouraged by the debates that we’ve had with suppliers and manufacturers across the industry because it’s going to be a pretty complex operation and one that we have to crack.
“Linked with this of course is the overhead line itself. I mentioned this earlier where we’re making reliability improvements and bringing on board the best of learning from Europe – or anywhere else if we find it.
“But in addition we have to look at not only the reliability improvements but it all has to be linked in to the logistics, productivity and construction methods being developed, always keeping in mind the long-term maintainability and sustainability across its life.
“Now, this is exercising a number of minds in Network Rail and in our suppliers and we’re seeking to work very closely with our suppliers to get the best possible system we can out of this opportunity to rethink how overhead line is constructed.”
Smarter switching
You mentioned IPC sixty one eight fifty as something exciting – even with its extraordinarily boring title.
(IEC 61850 is a standard for the design of electrical substation automation and part of the International Electrotechnical Commission’s (IEC) Technical Committee 57 reference architecture for electric power systems.)
“Ah, indeed. I’m personally really excited about this because I think it represents a huge step forward. First though a bit of waffle for you, forgive me.”
“I characterise this issue by saying that Moore’s law has caught up with the power industry – Moore’s law referring to the exponential expansion of computer capability.
“As a result, with our ability to handle and transfer huge quantities of data and the drive for what’s called Smart Grid Technology, we now have something called IPC 61850 which, although it has a tremendously boring name, really is exciting.
“It’s an integrated protection and control scheme which will enable us to rationalise the electrical distribution system and simplify the equipment we use to distribute the power.”
So what is the practical impact?
“This is really about changing the focus of the switches that we use. Over the years we’ve had to use heavy circuit breakers capable of breaking fault currents right the way along a route.
“IPC 61850 allows us to distribute the power – still enabling us to switch – but limiting the number of fault breaking devices we need. This has two benefits. The first is that this makes the switching less costly.
“But the second benefit is that we will no longer have to compromise between the electrical distribution needs of the system and the railway operations needs of the train operating people.
“It will enable us to think very carefully about using switching to focus on achieving better reliability for the operators while still maintaining that essential feature of distributing power… all at what looks to be at a considerable saving.
“By way of an example, at the moment the only switches that can interrupt a fault are at switching stations which are normally 10-15 miles apart; 10-20 on lightly-loaded routes. But actually in the middle of a section there may be what to the operators is a crucial junction – a turnback siding or whatever – that could do with being separately protected.
“Historically we’ve never been able to afford to accommodate that. But because we’re using much cheaper switches at such locations we can afford to perhaps break that section up a little bit and put something in place that’s protected and which would enable a fault on the overhead line to do far less damage to the train service.”
Does this equipment exist yet?
“We’re commissioning the first equipment in a substation south of the Thames this December. There are huge implications if this technology was to be adopted on the network and we’re planning a sensible migration path with a similar growth path in reliability.
“After the first substation we will be doing some more work in the North West to develop it further. We’re also planning for the GW west of Reading to be equipped with the new technology.
“The early electrification schemes – for instance the section between Manchester and the WCML – are scheduled to be operational in 2013.
“What we don’t want to do is prejudice our ability to build those schemes successfully by trying to push innovation in there too early. In the latter stages in the NW, as it moves through to the 2016 completion, maybe we’ll build some of it in then. But with GW now looking to be complete beyond 2016, of course we can afford to see more of the innovation in there.
“So the great thing – the fantastic thing and what I’m really enthusiastic about – is that we’re starting to see that our investment is turning into a rolling programme which will enable us to really exploit the technology and let us learn from the experience of one scheme to the next.”
And so the business cases for future lines become ever more attractive?
“Absolutely! For example the Midland Main Line is a very attractive proposition and we will be working on some development details on that.”
Perhaps keeping the teams together rather than losing them at the end of each scheme?
“That’s something we’ve always wanted to do but never seemed able to achieve!”
Renewed enthusiasm
45 minutes is a fair chunk out of Peter’s busy schedule so that’s where the interview had to end.
With parallel technologies racing on, our electrification colleagues are keeping up with developments of their own, driving down unit costs and achieving quantum leaps in productivity.
Pausing for breath, here’s a last word from Peter: “I really sense that a whole raft of factors – the political climate, the oil price and oil supply stability, the age of our rolling stock around the country – they’ve all come together to generate a will and enthusiasm to increase the electrification of the network.”
