Today the electric cars are the quickest on the road. The classic petrol muscle cars are vying for the silver medal.
Was it obvious to the designers, from day one, that this would be the case? Is it simply a power/weight calculation?
I'm congenitally leery of simple explanations -
For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE.
electric motors have a far more useful torque curve too. That's why train locomotives are not direct drive in the civilized world but run a generator and traction motors. If you want to pickup speed fast, there's nothing better. If you're hauling freight, and need starting torque, there's also still nothing better than an electric motor.
And electric motors can usually handle quite a lot of extra power short term
Incidentally there were some torque-converter driven trainsets in the US for niche applications e.g.
Basically a city bus on rails.
The later SPV-2000 was similar but an unreliable and difficult to service design it seems:
When AC traction motors were still quite large jackshaft-driven locomotives were pretty cool-looking:
I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo.
trucks are not fast, and most of the cargo is going to be batteries ...
Going uphill, some trucks have trouble keeping up with 55. Distributed motors might help. Also better handling going down hill.
And yes, i think we need at last 500kWhr or 7500 lbs. Assuming 1 mi/kWhr and 15 lbs per kWhr.
When they are not in line to get to a charging station.
Some people enjoy alternating between max accel and max decel.
Can't recall ever lining up for one. Mostly around here they're not used very much, not that there's a shortage of EVs but most people charge at home.
Businesses and public parking lots and state parks etc. often have them but don't tend to be able to figure out how to set the pricing on them or particularly care to they tend to be set at like $0 or 50 cents a kWh, depending, totally divorced from the price of gas or electricity for that matter.
I think they tend to install them because they get a tax credit or legislation mandates it in the case of public facilities but nobody really understands the tech once it's installed or knows how to make any money off it or cares to figure out how, only Tesla's network seems to have accomplished that in a meaningful way.
RichD <r snipped-for-privacy@yahoo.com wrote in news: snipped-for-privacy@googlegroups.com:
Just wait until battery tech gets better. You'll see 0 to 60 times of less than 2 seconds. Except now we are heading into the "no longer connected to the pavement" area.
They will need an optical sensor that looks at the road and at the wheel spin and keeps the car from breaking the tires loose at max acceleration. Need a big 100 foot long plate of hot rubber ensconsed dragway surface too.
Has anyone fashioned a Tesla motor powered dragster yet? Carbon fiber.
Remember the first corbon comp hulls and Kevlar sails in the America's Cup Race? It was also a ground breaking shift.
Ed Lee snipped-for-privacy@gmail.com wrote in news: snipped-for-privacy@googlegroups.com:
For one thing you are being presumptuous... again. Not very bright.
If there is a will, there is a way. Well, but that's not it. The point of multiple motors is to be close to the wheels, without energy lost in transmission.
torsdag den 14. april 2022 kl. 05.26.39 UTC+2 skrev snipped-for-privacy@decadence.org:
sure they make electric dragsters,
The FRA imposed some big-time regulation on passenger rail vehicle strength after WW2, yeah. I think those are _maybe_ getting finally relaxed a bit as of the past couple years? Not sure with respect to diesel rail cars on freight lines maybe I'm thinking of something else.
It's too bad as light weight DRCs that could run alongside freight equipment would open up possibility of service on under-served routes like e.g. Worcester MA -> Providence, RI and Boston -> Nashua, NH (just as local examples I know of) where there's some demand but hard to make the numbers work either as a public service or commercial venture with heavy rail.
Maybe, there were some DC motors that fit between the wheels then. The shafts on those in the pic are huge though, I think at the time around the turn of the century engineers were very conservative with this new technology and their main concern was ensuring they had enough torque hence the giant shafts. But there were many improvements in insulation, core material, bearings etc. from 1910-30 and the AC motor size decreased rapidly
Er, DC motor size rather the DD1 was DC-powered. Both AC and DC motors decreased in size over that time though for similar reasons I think
Locomotives don't give a durn about "pickup speed fast". The generator/traction motor is all about avoiding the complication of a gearbox and clutch which is harder to do at such power levels with good reliability. If you've ever seen a locomotive or locomotives pull a mile long freight train from a dead stop, you would realize "fast" doesn't enter into the equation and that a clutch would be toast very quickly. Even a hydraulic clutch would need to be very large and dissipate a lot of heat.
My dad was a dispatcher on the CSX railroad and complained about the unreliable Budd cars. Seems they often broke down and the headache of a blocked track was his. They were used for commuter trains because they could be configured into different sizes easily with one driver and could even driven by one car if the others broke down, which was not uncommon according to my dad. Some failures did not allow for any operation though.
The motor turns at the RPM of the wheels. Even for an electric motor that is slow. So to get adequate torque at low speed the motor needs a large diameter. Compare to BEVs today where the motor is very compact, but turns at 9x the wheel rate which is much faster than the locomotive wheel rate. Some of the old steam engines had wheels tall as a man.
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