Prices for the new Vauxhall Ampera have been announced now.
Details :-
www.autoexpress.co.uk/news/autoexpressnews/260947/vauxhall_announces_ampera_price.html
Are there any other hybrid car makers building cars where the petrol engine only drives the generator ?
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It is only really how diesel trains work. If the diesel engine drove the trains wheels it would need a gearbox and there isn't any strong enough for more trains so that is why they have a diesel generator which powers the motors.
I have often too wondered why their are not more cars which use the system.
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>> I have often too wondered why their are not more cars which use the system.
watch this space. The days of the gearbox are limited.
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Still aimed at the USA I see... hence they are using an inefficient petrol engine... I suppose a small diesel is too noisy for them...
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There are plenty of diesel powered trains that are not diesel-electric but use a hydraulic transmission.
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>> I have often too wondered why their are not more cars which use the system.
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£££££££
The diesel rail=cars with underfloor engines are diesel hydraulic (generally Voith transmission), it is expensive, 15 years ago they were over £50k each and they are cheaper than electric transimissions.
To achieve anything like what you achieve in a car with a 5/6 speed gearbox you need an AC motor with a variable voltage variable frequency invertor to drive it. Not cheap - but a true CVT. Many of the new trams have drives like this.
Most diesel electric locomotives you see use AC Generators and DC motors and are not CVT but have one or two stages of field weakening (effectively gears) for the motors. The exception being the HST which has no field weakening because it does not spend much time at low speed and does not haul heavy trains, run one at 5mph for long and the motors will overheat.
The aim with most locomotoves is high starting torque, unbelievably high if you imagine starting 5000 tonnes from rest.
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>> The diesel rail=cars with underfloor engines are diesel hydraulic (generally Voith transmission), it is expensive,
>> 15 years ago they were over £50k each and they are cheaper than electric transimissions.
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Err, not in the UK they aren't... most of the modern stock with underfloor engines are actually diesel electric, Voyagers for instance use 750hp Cummings turbo charged engines driving a generator and feeding the electrics on the coach and a 750v DC electric motor which drives the inner axle on each bogie using a cardean shaft. Remember that modern stock is full of stuff that uses electricity, they have to have a generator as batteries alone couldn't cope...
The advantage they have over cars is that there's a lot more room under the coach than under the bonnet of a car!
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>> >> The diesel rail=cars with underfloor engines are diesel hydraulic (generally Voith transmission), it is
>> expensive,
>> >> 15 years ago they were over £50k each and they are cheaper than electric
>> transimissions.
>> >>
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>> Err, not in the UK they aren't... most of the modern stock with underfloor engines
>> are actually diesel electric, Voyagers for instance use 750hp Cummings turbo charged engines driving a
>> generator and feeding the electrics on the coach and a 750v DC electric motor which
>> drives the inner axle on each bogie using a cardean shaft.
OK most of the modern, fancy long distance stuff is diesel electric, but I though most of the more mundane / slightly older units (Class 158 for example) are diesel hydraulic or diesel mechanical. My understanding is diesel electrics were largely avoided (apart from the Southern Region) due to cost and weight compared to hydraulics or mechanical - at least until very recent times.
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I'll correct my statement, most modern (ie non-BR designed) is actually a mixture of both! The 22x classes are D-E, but the 185 and 180s are both hydraulic!
The original DE units were the Hastings ones... Though I prefer the Blue Pullmans myself!
Sorry, we're hijacking the thread!!
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What an ugly-looking car ... I'll stick with The 'Yo'.
:)
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GM are considering changes to the design of the Ampera/Volt so the engine in some circumstances does help drive the wheels directly. It has problems maintaining speed on motorways. That is what I had read.
www.autoexpress.co.uk/news/autoexpressnews/253672/shock_rethink_on_ampera.html
Sounds like if they didn't make changes it could have problems at speed.
Last edited by: rtj70 on Tue 14 Dec 10 at 19:19
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Oh dear, surely pretty much a complete re-design if it's changed to a hybrid at this stage.
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Yup
Thats a big engineering project to change that, plus it seems they dont have any IC for hybrid techology and will have to license it in.
Ouch!
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If the article is true - but they do quote someone at Opel. Ouch indeed. Or release it and it will be poorly received.
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Sounds on a par with GM's lack of engineering nous.
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Using an engine to generate electricity to turn an electric motor is almost certainly less efficient than driving the wheels directly (although having a seperate engine that can run at maximum efficiency independent of road-speed will mitigate this).
I see GMs system having 3 significant advantages over typical hybrids/electrics:
The engine enables a largely electric vehicle to have no great range limitation with the current refueling network - running low in leccy? - burn petrol.
The huge weight of batteries required to give an electric car >100miles of range can be reduced, very likely by more than the additional weight of the petrol engine and gubbins.
From a packaging point of view the engine can go pretty much anywhere, and the motors can be in/near the driven wheels - as the connection between the energy production (engine or batteries) and motors is simply cables a more space efficient design can be made than a typical hybrid.
Early days for this technology on the roads but looks a far better prospect than fuel-cells.
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Way back in the mists of time - well, late 70's ... I had a power hungry Sun motor tester in the back of my van which I powered up via a lorry battery running through an inverter.
Come the 80's and an even bigger SMT 1080 jobbie, I ditched the inverter and bought a cute little quiet running Kawasaki petrol generator - so I can see how now, in the naughties, a cute little quiet running engine running a leccie, is not such bad idea.
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So Vauxhall is the only one to think different ? - RattleandSmoke
