HST 2 ideas

Keelar001 · Post by **Keelar001** » Tue Jun 06, 2006 9:44 pm

alexnick wrote:The 444s and 450s have great riding qualities - I don't know about the diesel versions. I'm afraid I don't like the 170s, however - they are very cramped inside - I'm just too tall for their seats! The 165/6s are much better if you ask me.

Nick

Dessies ride reasonably, although they have a nasty habit of rolling, especially around 40 mph on rough crossings - try one on single yellows on the the Down Fast at Wimbledon. Nasty wallowing clattery things. For all that - and it pains me to say it - they do have much to commend them over a 458 or a Slammer.

442s are the best riding electric units I've sampled- all the joys of a Mk3 with the English Electric howl under the Motor-Brake.

Not sure how distributed drive would affect ride quality; especially on a coach with one powered and one unpowered bogie. Perhaps mounting the traction motors on the body and driving via a cardan shaft and gearbox would be the answer? Matt?

BR7MT · Post by **BR7MT** » Tue Jun 06, 2006 9:47 pm

Keelar001 wrote:Perhaps mounting the traction motors on the body and driving via a cardan shaft and gearbox would be the answer? Matt?

I'm not Matt, but I know a bit about transmission dynamics

Generally it would be a bad idea. There would be more maintenance required for such a system compared to bogie mounted traction motors.

Regards,

Dan

enotayokel · Post by **enotayokel** » Wed Jun 07, 2006 5:08 am

Isn't that how the Voyagers have their drive set up?

arabiandisco · Post by **arabiandisco** » Wed Jun 07, 2006 7:24 am

enotayokel wrote:Isn't that how the Voyagers have their drive set up?

Well in that case it's certainly a bad idea.

alexnick · Post by **alexnick** » Wed Jun 07, 2006 12:01 pm

I don't know - some of the trackwork on the Southern Region is appalling, and would make any stock roll unbearably. I noticed that there was a really bad 'wet spot' (I think that's the corect terminology) at the Milford level crossing on the up line (fixed the other week), but you'd only see it if you were standing waiting to cross - you wouldn't notice it riding on a 444/450.

I rarely travel in 442s these days - I never use the Weymouth line - but I remember them being good. VEPs used to be good, until they stopped maintaining them in the last couple of years!

Still, I'm convinced trackwork is the key to ride-quality. Anyone who looks at track-laying standards on Swiss railways will know what I mean!

Nick

Keelar001 · Post by **Keelar001** » Wed Jun 07, 2006 10:18 pm

Wet spot is the correct term - tends to create a vertical rather than lateral movement, since the track distorts vertically...

alexnick · Post by **alexnick** » Thu Jun 08, 2006 9:23 am

Thank's for that!

BR7MT · Post by **BR7MT** » Thu Jun 08, 2006 10:34 am

If anybody has read the latest issue of Modern Railway - the bit about HST2 hybrid power is a good read. But the author has missed the main idea of just using the battery and getting rid of the diesel engine entirely...

Regards,

Dan

mattvince · Post by **mattvince** » Fri Jun 09, 2006 9:12 am

Dan - That's what came to mind too. Replacing one MTU/Paxman/Cummins/etc with the equivalent in Duracells might be something to investigate. Perhaps something to be trialled in a redundant '43' power car - possibly with an '87' coupled inboard to provide traction power (better still an EMU PT* vehicle)?

viperskil · Post by **viperskil** » Fri Jun 09, 2006 11:07 am

Yes, but Batteries take quite a time to recharge and as the HST 2 is meant to be available for as many routes as possible you would need battery recharging facilities at practically every depot in the UK. This wpuld cost many millions and be far slower than the "top up and go" method used on current diesels. Also what happens if it does run dry on the mainline you woldn't be able tp top up from other locomotives etc to enable yourself to get up to the next filling stop causing huge delays in the wait for a pilot locomotive.

BR7MT · Post by **BR7MT** » Fri Jun 09, 2006 11:16 am

That is why you add short sections of OHL to terminii, major juction stations and stabling points. Or to save costs you use third rail.

Trust me on this - I know it is possible but I can't publically reveal why.

Regards,

Dan

mattvince · Post by **mattvince** » Fri Jun 09, 2006 9:40 pm

Dan - 'Informed Sources' not quite as well informed?!

Fitting out depots would not be a problem - possibly just a question of adding another HV cable network alongside the existing depot shore-supply (necessary as diesels still need to have their batteries recharged when the diesel is turned off overnight). If combined with the depot improvements which would be necessary to support HST2 (of whatever power) then it's cost-effective.

How long to recharge: is four hours enough? GNER would be a good place to start, the 25kV supply would ensure by the time you reach Edinburgh, the batteries would likely be at full charge - even if fully discharged upon leaving The Cross. The problem is getting enough of them. Replacing a whole Valenta, alternator, turbocharger, fuel kit, fuel itself, etc, might lose enough weight to allow enough batteries within the 70t limit. Further to the suggestion of an EMU PTx vehicle - perhaps a modified Mk3 TGS instead - then it could be trialled in normal 125mph service with a conventional (MTU'd) '43' on the other end giving 50% of the power and an insurance policy.

On a slightly related front - a spot of dodgy maths using the Davis equations quoted in Joe Realmuto's FCalc 2.0 documents*, for an 84t 10.2m^2** Bo-Bo electric locomotive hauling forty-two 100t HTA hoppers at a steady 15mph for fifteen minutes would require at most 1.6t of batteries (bear in mind it is hauling 4200 tonnes of train). Now, in our notional electrification program, that would fit in very nicely as having the ability to pull the HTAs under the loader without having to resort to out-of-gauge solutions such as RBW-Rheinbraun's side pantographs. Possible other uses include moving intermodals into/out of their terminals, where OHLE cannot be used and third-rails present a safety hazard to staff.

*assuming Roller Bearings
**guesstimated from GE/GN8573

BR7MT · Post by **BR7MT** » Fri Jun 09, 2006 10:41 pm

Also Informed Sources talks about NiMH batteries. Old technology I'm afraid!

The future is LiPo with higher energy density (I think thats the correct technical term) i.e. it stores more energy per kg than an NiMH, in fact it stores substantially more.

The only problem is passing the far/explosion risk past HMRI, but it has been achieved in Japan.

Regards,

Dan

mattvince · Post by **mattvince** » Sat Jun 10, 2006 5:31 pm

Slight correction to the calculation - I warned you it was dodgy - I foolishly forgot transmission losses of 10%, so the answer is actually 1.8 tonnes. This is ignoring completely the conservation of energy factor, power draw of auxiliaries, etc. A two-tonne battery pack still sounds about the right weight to achieve the aim. All of this equation was worked out on the basis of 50Wh/kg - the more efficient the battery, the smaller it can be.