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electric midget?!

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zimmy

zimmy

Jedi Knight
Offline
well, my plan is to take a
generator and run an electric
motor from it to power the car....
yes, i know, it sounds so simple.

heres where i need some help.
i have a 240 volt, 20 amp,
4000 watt generator.
what size motor can i run
and how much"horsepower"
can i expect to get from it?

i really dont see how this
wouldnt work for a small
vehicle...
a traveling car could get 120+
MPG!.....any ideas, suggestions?
 
Where to begin, basic physics. Is the generator motor capable of powering the car by itself? It better be, because by the time you take its output and then use it to make electricity, then feed it to an electric motor and only THEN actually turn a wheel, you will have lost quite a bit of the generator motor's power output in system losses and the inherent inefficiency of conversion.
Like the "stranded on an island with a bag of grain and a chicken" problem, you mustn't feed the grain to the chicken and expect to get it all back as eggs. The answer is to kill and eat the chicken and then settle back and eat the grain.

There is a very good reason you don't see this setup on the road. Even if it worked well, it would give better mileage if you just ran the car on the generator's gas motor. You're going to be listening to the roar of the motor either way.

Glen
 
well im no physics-ian and assumed there was
a catch somewhere!!
guss i could make a nice go cart with the
motor :wink:
it just seems that 240 volts could
run more than a 5 HP motor....
any more comments? ........z
 
Glen,

The trick is to run a small battery pack along with the generator. The battery pack powers acceleration, while the generator charges the battery pack and runs the car down the road in low power cruise situations.

And you will see this configuration ALOT in the near future as it is the design premise behind the Chevy Volt. It was also a popular "hack" for some of the EV's available in CA in the 90's.

Zimmy,

I would love to see you attempt this project, but I think even with the generator on hand, you should expect to budget $3000-$6000 for batteries, controllers, a decent motor etc. And expect to drive like a granny on qualudes if you want to get any range/gas mileage out of this set up.
 
I think if you use ohm's law you will find first that 240V * 20A = 4800W, then the manufacturer expects 83% efficiency, therefore 4800 * 0.83 = 4000W. Then look at the conversion factor 1HP = 0.746 KiloWatt, divide and you get 4 kW / 0.746 = 5.36 HP

Use a battery pack like the Opel and how fast can a car go with 5.4 HP? The battery pack will get up to speed, so it's only a question of wind resistance and recharging the batteries for continued operation. If you want to drive 100 miles, the car's motion resistance will equal the power input.
 
If you read the "Amazing-75-MPG-Hybrid-Electic-Car" article, you will see that the budget for the project was 1500 1979 dollars (which is about $789,500 with the dollar at its current value). And that guy was able to build with mostly junk yard parts that are no longer readily available.

Not saying the project is not doable or worth doing, but you should definitely do some serious cost-benefit analysis before starting the project.

Consider also that you could probably pick up 948 engine for nearly free these days and have a car that gets 45mpg, a 300 mile range, and will travel almost at modern highway speeds.
 
Sorry - I know this is a wee bit OT but:

Can I pick up a small LBC lump with tranny for an MG 1100 somewhere? I have a line on an 1100 that has no running gear.
I bet an 1100 could be made to produce some good mpg numbers!
Oh - and it would have to be very inexpensive in order for the project to make any sense at all.
 
Well Morris, a real quick look around at what might be available...

72 VDC motor with controller - $699

This appears to be a good start, I'd guess these are the most expensive components.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]A QUALITY ADC MOTOR WITH A GE CONTROLER MATCHED TO IT. THE MOTOR IS A 72V DC MOTOR THAT IS SETUP WITH SOME NICE FEATURES ALLREADY FOR YOUR EV PROJECT. IT HAS A 19 SPLINE TRANSAXLE SHAFT TO RECIEVE YOUR HOOK UP.[/QUOTE]
 
Rick
The MG1100 is transverse.
The cheepest transverse setup IS the MG1100 one.
Bill
 
Thanks Bill, maybe we can talk more about this tonight at the club meeting.

Rick
 
I have seen an actual electric midget at my shop. It was converted from an old electrtic mail jeep. It was very interesting, 72 vdc. Lots O batteries! Unfortunatally that gentlman passed earlier this year in a crash with that Midg.

Heres some food for Thought. a 3.83 Hp (Peak 10hp) 48vdc motor will run a golf car up to a maximum of 35 miles (At no load) utilizing a 220Amp Hour Battery Pack. A 20 Amp Genereator alone couldnt do anything near as such. Under loads it will have requirements of up to and over 400 amps. AC is much different and can be made to extend run times.

Note those Curtis and GE controllers are $800-$1200 easily Chargers start at $400 for good 21amp output types, and a Good Deep Cycle 6 volt battery retails for $125 these days.

I once thought of such a conversion and since all of the parts sell for such High amounts themselves, the ideal solution would be to obtain an old electic forklift to donate parts from. Mate the 10hp+ motor threw the 4 spd trans, utilize the controller, and the potentiometer (Pot box)and the charger. Most DC motors are cpable of 5500rpm so you could build a midget with a gear such as 4:55 to give you some bottom end umph and still cruise up to 60 mph.

The biggest problem is unless you can use super expensive Lithium Ion battereis, Lead Acid are Very heavy. And you'll need much more room than a trunk full to get any range out of them.
 
Thanks Scott, yes it's mean old Mr. Physics popping his uply head up again. There's gotta be a reason Chevy is having so many problems getting the Volt out the door.
There is a market, they would sell like hotcakes.
There are a lot of hurdles.
I'm sure I'd be farther ahead getting something like the 1100 and then tuning that baby for extreme economy.
 
I just started selling LSV's Street Legal Low Speed Vehicles. It seems everytime the major manufactyurers pout there heads together they release a neighborhood vehicle (30mph and less) Like the GEM from Crysler.

This is one of the coolest of seen yet. Coming soon. Goes up to 50 Miles for $1.00 worth of electricity. (Guess that depends how much your kilowatt is.) But if these are out now than full size shouldnt be too far behind

https://tomberlin.net/electric-vehicles/tomberlin-anvil-electric-car
 
Ha!
For some reason it reminds me of the King Midget...

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Built by Midget Motors Corporation in Athens, Ohio from the 1940s through the 1960s[/QUOTE]

aams53-i.jpg
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]There's gotta be a reason Chevy is having so many problems getting the Volt out the door.[/QUOTE]

IMHO, the problem is stupid corporate leadership. The same leadership that said "SUVs will always been in!"

Chevy put the EV1 on the market in less than 2 years. The only thing holding up the VOLT is Chevy's reluctance to accept the fact that SUVs won't sell when gas is over $4.00/gallon.

L-ion batteries are coming down, and several small suppliers now offer them for homebuilt EV'ers. It's only a matter of time before the homebuilt EV becomes a practical option for wrenches like us.

Here are a coupla links to keep you inspired until that time:

https://www.acterra.org/ev/

https://www.evcl.com/914/
 
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