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Average Joe
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Discussion Starter · #1 ·
I can't quit thinking about a DIY Plug-in hybrid.

Things required:

1) Very small, high powered gas or diesel engine
2) High efficiency, high output alternator
3) Computer control system

I think a ~80hp 1L 3cyl turbo gasser would make a perfect long-haul generator. Does anyone know of a new engine readily available like that? Either gas or diesel would be fine. It could possibly go under the hood if the arrangement were efficient.

What about the alternator? This seems like one of the most difficult pieces. Would a forklift or other large motor work as an alternator?

The computer control is definitely doable. For a proof of concept, one could just run a gauge that shows when the batteries are at 75% DOD. A regular start/run switch could run the generator and a knob or slider could control the output. An ideal solution is a system that automatically starts/throttles and stops the generator to keep the batteries from dipping below a certain depth. It really wouldn't be that difficult to develop. I could have a system working with display in a few months for under 5k. If many people wanted it, we could get it down to 1-2k for each control center.


This sort of setup I believe is the way things will go in the future, but why haven't I seen anyone doing it now?
 

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I can't quit thinking about a DIY Plug-in hybrid.

Things required:

1) Very small, high powered gas or diesel engine
2) High efficiency, high output alternator
3) Computer control system

I think a ~80hp 1L 3cyl turbo gasser would make a perfect long-haul generator. Does anyone know of a new engine readily available like that? Either gas or diesel would be fine. It could possibly go under the hood if the arrangement were efficient.

What about the alternator? This seems like one of the most difficult pieces. Would a forklift or other large motor work as an alternator?

The computer control is definitely doable. For a proof of concept, one could just run a gauge that shows when the batteries are at 75% DOD. A regular start/run switch could run the generator and a knob or slider could control the output. An ideal solution is a system that automatically starts/throttles and stops the generator to keep the batteries from dipping below a certain depth. It really wouldn't be that difficult to develop. I could have a system working with display in a few months for under 5k. If many people wanted it, we could get it down to 1-2k for each control center.


This sort of setup I believe is the way things will go in the future, but why haven't I seen anyone doing it now?

First time poster here!

I have just started studying up on the electric car world. But I have been thinking the same as you. How much engine do you need to power the batteries? I was thinking of using a small turbo diesel engine to do it. Couldn't you string together a couple 200amp alternators or a few generators off small back up house generators? Sorry for any ignorance this is still new to me and I'm learning.
 

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There's already an active thread on the subject going on here:

http://www.diyelectriccar.com/forums/showthread.php/would-best-way-make-series-hybrid-13709.html

As I've pointed out over there, my problem is that in a standard config you probably end up with a primarily gas vehicle in the end. The engine and genset will add weight and space to the project, which reduces the battery bank to a point where the genset is going to have to be used virtually all the time for any effective range. Then you're worse off than current hybrids because there are significant losses in the process of the chain of conversions, lowering efficiency.

The EV pusher concept is probably a better distribution of a series hybrid. You can find the best example here:

http://www.jstraubel.com/EVpusher/EVpusher2.htm

Take an total EV and push it with a total ICE. When detached, it's just a PEV, then attached its a long range series hybrid that can become EV only at its destination. Configure the EV to cover the vast majority of in town trips.

It's a more efficient distribution of the hybrid components.

Even if you do a series hybrid, trailering it would be a more effective distribution than installing it in the vehicle.

ga2500ev
 

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Average Joe
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Discussion Starter · #4 ·
I can't imagine that the weight of a 1L engine w/5 gallons of gas on-board is that bad.

Perhaps what I'm picturing is a vehicle with 100 mile range to begin with, which would get cut down to say 80 or so with the extra weight.

How is chevy planning on doing this with the volt? I know they are proposing a similar system.
 

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I can't imagine that the weight of a 1L engine w/5 gallons of gas on-board is that bad.

Perhaps what I'm picturing is a vehicle with 100 mile range to begin with, which would get cut down to say 80 or so with the extra weight.

How is chevy planning on doing this with the volt? I know they are proposing a similar system.
Check the other thread mentioned above, it is well worth reading.

And as far as the 200 amp alternators.....remember we have to talk about power, not just current. a 200A 12V alternator is only 2400W. It takes 746 Watts to make one horsepower. 2400/746 is only 3.2 HP. It would take 12-15HP do drive a car. So you would need 4 or 5 of them. Then, you have to step it up to battery voltage from the 12V output. This will be less efficient.

A better solution is a 3 phase AC generator ( say a 400 Hz one for less ripple) simply rectified and filtered to put out the voltage and current required for driving. This would require an excited field and brushes, but you could have good voltage regulation through this setup. And you would not need a 1L engine, anywhere from 250 to 600 cc would do depending on RPM and power output. Remember, we only need about 12-15 HP supplied to drive this car. We are talking about a 9-11kW generator, less if you are comfortable with using some current from the battery pack to drive on long distances.

Think small motorcycle engine. My belief is a genset could be made for this purpose and weigh less than 300lbs, be packaged well enough not to be an issue in even a conversion, and be reliable.


Jeff
 

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Check the other thread mentioned above, it is well worth reading.

And as far as the 200 amp alternators.....remember we have to talk about power, not just current. a 200A 12V alternator is only 2400W. It takes 746 Watts to make one horsepower. 2400/746 is only 3.2 HP. It would take 12-15HP do drive a car. So you would need 4 or 5 of them. Then, you have to step it up to battery voltage from the 12V output. This will be less efficient.

A better solution is a 3 phase AC generator ( say a 400 Hz one for less ripple) simply rectified and filtered to put out the voltage and current required for driving. This would require an excited field and brushes, but you could have good voltage regulation through this setup. And you would not need a 1L engine, anywhere from 250 to 600 cc would do depending on RPM and power output. Remember, we only need about 12-15 HP supplied to drive this car. We are talking about a 9-11kW generator, less if you are comfortable with using some current from the battery pack to drive on long distances.

Think small motorcycle engine. My belief is a genset could be made for this purpose and weigh less than 300lbs, be packaged well enough not to be an issue in even a conversion, and be reliable.


Jeff
Great information! I was thinking a small back up house generator would work. but I wasn't sure how much power you needed to do it. The push EV is a good idea but if i can get away with having a 2-300lbs ICE always on board for long range , i would prefer to have it. I have had passengers weigh that much!
 

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You can really cruise a 3500lb car @ 75mph off of 11kW?
Well, that depends on the car.

The EV-1 could do it, but it was optimised for aerodynamics and EV usage. Low rolling resistance tires, brakes that pulled the pads away from the discs, the shape, underbelly was smooth. Many things were optimized.

Not likely with a conversion. But, if you have 11kW from a generator, and it takes say 15kW to drive it at 75mph....then the draw out of the battery is 4000W/144V=27.78 A from a 144V system, and if you used Trojan T-105's...that is about 400 minutes. 400/60=6.67 hrs, and at 75mph you have travelled 500 miles before you are depleted.

That aint so bad, is it?

Jeff
 

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I can't quit thinking about a DIY Plug-in hybrid.
3) Computer control system
An ideal solution is a system that automatically starts/throttles and stops the generator to keep the batteries from dipping below a certain depth. It really wouldn't be that difficult to develop.
?
Available from Trace inverters...used on busses and RV'.
It works really well.
I have 2 5,000w inverters in a bus at work and to "AutoGen" is a simple scroll thru on the control panel.
Of course you don't run the AutoGen feature when parked inside, it tends to come on when your not thinking and exhaust gassing the garage.
So to make the system EV specific you could have a control where if your plugging in, AutoGen is disabled. and it needs to be a button flick on the dash.

If you can make lil controls like this on your own, it wouldn't be that hard to get a FEATURE list together.
I could look over the inverters I have, and also my bus friends.

As for the diesel power plant to run the Generator, have you seen any info on emission requirements?? Specific on emission requirements for the HYBRID GenSet?? I think the emission requirements for the Diesel power plant on a stationary GenSet is
If it is mounted in your vehicle somebody is bound to tail pipe sniff it sooner later.

I have a manufacturer here in town that makes a 8 Kw car-Alternator-shaped 12 inch round 8 inch thick generator.
I will go by there and see if he has other versions, verify A/c or D/c output and look at his diesel engines.

I mounted one of these units on a bus, driven off the Drive motor, no real loss in drive power.
 
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