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Discussion Starter #1
My new build is happening :) Got the first tubes of steel cut and a buddy took my pencil and paper drawing and is giving it the 3d treatment :)

Its going to be a hybrid, that much I know. The goal is to make it reasonably light and as slick aerodynamicaly as possible.

So far, its looking like 9 sq feet of frontal area and .17 (hoping) cd

Ok, heres a question that has me stumped:

I have a 7hp ICE I want to use as a range extender and Im not sure how to best go about it. I could have it drive a second sprocket on the electric motor, or a gen.

Im using a: D&D ES-15-6 Series Motor

so option a) run it on a second sprocket on the electric motor so ICE has a centrifigual clutch and when the clutch engages, the motor drives the sprocket (The first sprocket would be connected to the rear drive wheel) so, im guessing the electric motor thinks the car is "coasting" or going downhill. Right?

benefits to option a: simple setup, there is room to mount the ICE on a plain that a chain can reach and line up to the electric motor.

Less mechanical drag, 1 new chain entering the mix.

Drawbacks: would the e-motor draw amps (or generate them) if turning something close to its max rpm?

Mounting the ICE where it would have to go for this would put about 70lbs up above the emotor and kill a good luggage space area.

Benefits to option b) ICE could go low and close to cooling air (To the right of the rear passenger down low)

If the ICE is turning a gen that is matched via the right pullys to output say 80v and 60a in theory the ICE/Gen combo could be switched to replace the controller at highway speed and adjustments to cruise speed could be made with the ICE's throttle. (?)

If the Gen output is below the Batts max charge voltage, it could charge the batts while one was in a store drinking coffee? (I know this was covered in another thread, but I was unclear on the answer)

Drawbacks to option b) 2 stages of losses: the loss coming from the ice to the gen, from the gen to the e-motor

Thoughts?
 

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How certain are you that the range extender will be needed? If you're 90% sure of your daily/average need you might be best to go without it and gain efficiency. Or use the space/weight/$ to install more battery capacity.

Direct-drive i.e. generator driving wheels is more efficient (power conversion efficiency + not needing a generator) but I'm not sure a centrifugal clutch won't overrun. Also most smaller ICE's are not very efficient so if part of your goal is environmental in nature you'd be better off mounting a charger and drinking coffee where they let you plug in to charge up. :)
 

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Discussion Starter #4
Weird thing about where I live (Palm Coast FL) is once I get out od the town itself, its 60 or miles plus to anywhere I would go. Orlando or Jacksonville. I work from home but these are places I go to often. Plus I do a lot of driving in general to Tampa and the north east.

Im thinking hybrid is the best way to get my needs met :)
Tom
 

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Either put 24 200ah cells in it, or stay with the ice, running a combo is a foolish endeavour.

200ah would get you to Tampa, not sure if you would have enough to return without charging, depends on how much weight you have to move.

See the problem is not distance at least to some extend, the problem is that a TS cell can take 3C charging, but where are you going to find a place that has that much power for charging it up in reasonable time.

Until the infrastructure is there to charge at a reasonable rate, an EV is what it is atm.

Roy
 

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Discussion Starter #6
I respect your opinion Roy, but disagree. In my opinion, the right tool for the job (building a 100mpg 2 seat trike that costs under 10k) is to use a very small ICE for the highway where its the most efficient and use Electric drive for the "in town" portion of the driving profile.

Different strokes I guess.
 

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Tom,

My driving sounds like yours and I have been considering a hybrid vehicle similar to the one you describe.

I am planning to remove the front wheel and handlebars from a small Honda motorcycle and attaching a front sub-frame from a small disposable econobox.

Unfortunately, when I scavenged the sub-frame, I didn't take all the useful items I should have. I took the steering gear (small rack and pinion) but left the suspension and brake elements which would have been usable.

Economically and ecologically this type of vehicle makes a lot of sense to me.

Have you checked the Reverse Trike Forum?
http://reversetrike.proboards.com/index.cgi
 

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Discussion Starter #10
Progress!

After last weeks setback (mis-measured the interior area and no room for rear riders legs) we got it re-welded today and its looking (and sitting) good!

Also got a couple large go kart seats I will pad and upholster later, they are sooo comfortable.

Also I believe I found some wheels by accident. narrow VW wheels are plentiful but fairly expensive, I may get the rotors drilled and use some temp spare wheels to go with the conti eco contact wheels I got shipped (165 60 15) low RR from a smart car :)

Here are some pics
 

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Discussion Starter #11
I was pondering just now and had a neat idea, want to run it past everyone :)

I want to do a serial hybrid, mainly for the ability to keep the diesel drive engine in its bsfc "sweet spot" but recently to engage what Ill call FVT style driving. (The FVT Ale car, I was reading a few posts about it and they employ a strategy of driving the car under power from the ICE and charging the batteries, then shutting down the ICE and running under battery power. I likee! :)

Anyway, here is what I was thinking. As serial hybrid, a portion of the ICE's output would be for running through the batteries and right back out the controller toward the drive motor, the inneficiencies do add up.

Also, for a highway speed capable vehicle, I have a feeling 72v will be "almost good enough" for speeds of 70 or 75.

(Sure would be nice to keep it at 72v though, Alltrax controller, cheaper chargers, less batts etc)

So, if a portion would be for motive power and a portion would be for charging. perhaps I go series AND parallel hybrid...

Building this would be easier then it sounds, I think. I could have a centrifigual clutch on the diesel with 2 sprockets coming off of it, one to the drive motor to 'push it" at high way speeds and 1 running to a much smaller gen motor to output say 86v (to charge a 24 cell lifepo pack) x 20a

Unless I am missing something, here would be the pluses and minuses:

Pluses:

Motive diesel power would get transferred to the drive wheel with only the chains resistance.

It would help the electric drive motor where it needs it most, highway high speed droning.

It would still be able to charge the main pack.

Minuses:

The diesel would be spending some of its time not smack dab in the middle of the bsfc sweet spot (But not too much it would be pretty constant at 70mph)

Comments? :)
Thanks
 
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