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Discussion Starter #1
here is the link to the alternator conversion booklet.

http://www.industrial-scientific.com/motordrives_motors.htm

this was asked about on the EVDL.

i'm a little skeptical of the power output of this modification.
I've sent some questions to the company.
We'll see what I get as a reply.

Does anyone want to go "half-sies" ? lmk

I have a printing of "Alternator Secrets" that I bought a long time ago from (i think)
Lindsey Publications in pamphlet form.
Then, several years later, found it later as a pdf on the www.

Basically, it talks about rewiring to get higher voltages out of an alternator.

afn
T
 

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Discussion Starter #2 (Edited)
Replying to my own message :p
Maybe this discussion should be in the "technical" area or the "EV discussions" area(?)
Mr. Moderator, feel free to move this where U think best...

I sent an email to the Questions page at the aforementioned website.
I received a reply very quickly...
Here is the text---

I ASKED--
Hi, In the "Alternator to Motor" booklet, does the conversion require any of the following: welding(?), machining(?), rewinding with varnished copper wire(?), varnishing/shelacking of rotor(sp)(?) Also, what about the electronic controller? Is a tested, working schematic provided for the controller?? Your picture/video shows the alternator running as a motor with no load. Have U determined the torque output under actual load conditions, such as driving another alternator connected to a load resisotr??? plmk thanx



REPLY RECEIVED:
Thank you for your questions.

The conversion does not require any of the operations that you have listed.

The Alternator Conversion Manual details how to rework the alternator so that it can be driven the same as a brushless motor; that is, when the procedure in the manual is completed, the resulting alternator can be treated as a brushless motor. Schematics for controllers and drivers are not included.

We are releasing a controller and driver kit in early 2008. At that time we will also release torque and power output curves.

Thank you,

Les Nelson
Chief Engineer
78Systems, LLC.


CONCLUSION:
Without a "driver"(controller) schematic, turning a 3phase alternator into a 3phase motor seems moot. Do not know if the sliprings are retained(?) Lowpower 3phase controllers are fairly easy to construct if U have some steppermotor background. But, high-power steppers are a little different animal. Also, since the video shows the modified alternator running WITHOUT load, it really doesn't show the capibilities of the modification. I have decided not to purchase the conversion manual at this time. I have several alternators that I have salvaged off several junked vehicles. I will look into this more after I get my EV back on the road..... afn T
 

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here is the link to the alternator conversion booklet.

http://www.industrial-scientific.com/motordrives_motors.htm

this was asked about on the EVDL.

i'm a little skeptical of the power output of this modification.
I've sent some questions to the company.
We'll see what I get as a reply.

Does anyone want to go "half-sies" ? lmk

I have a printing of "Alternator Secrets" that I bought a long time ago from (i think)
Lindsey Publications in pamphlet form.
Then, several years later, found it later as a pdf on the www.

Basically, it talks about rewiring to get higher voltages out of an alternator.

afn
T

found a little info on this without purchasing said booklet...http://www.fossilfreedom.com/alternator-conversion.html. Of course I had already purchased the booklet. Oh well...I'll find out what the differences are between them and let you know.
 

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Update....got the booklet, very comprehensive. But, definately requires what I would call a complex controller to make it spin up.
 

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I also was looking into getting the booklet when I ran across your posting (and forum). From the "hybrid" description on their website, it makes it sound like the conversion doesn't result in a regular permanent magnet brush-less DC motor. You said you'd found the web page showing how to convert to a PM BLDC, but it must not be the same "hybrid" they're describing.

If the company comes out with a controller, as they say, this is a potentially big bang for the buck high power motor option..."efficient" as it might be.

I've got some 28V 300A alternators that should put out 7 or so HP at 2,000 RPM (about a quarter of the speed they've got to run for a full 300A).

Anyone know of sources for strong, doughnut magnets? I've got sources in China for up to 5Kw BLDC, but these are "iffy". Anyone know of something closer?

Thanx.
 

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Discussion Starter #6
Hey LEVitator,
All alternators have cheap cheap oilite bearings. To make a dependable
motor, these would have to be replaced with some good, sealed bearings.
U might have to machine the aluminum housing to get the bearings to fit.
A permanent magnet rotor, like on the Fossilfreedom.com would be more of
a challenge to build, IMHO, than the booklet version. Both versions would
require new bearings for a long-lived motor. And, of course, some kind of
3-phase controller :)
 

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EVMan,

I'm not sure how good the bearings are, though industrial bus rated are surely better than those on alternators from ordinary car and truck alternators in the 12V 100-200A range. They've got to be to provide years of continuous service. Still, replacing these with better ones makes sense, even with the machining expense, since I don't know the condition of the bearings.

After pressing out the claw shaped pole covers from one rotor, I'll be looking for good Neodymium rare earth magnets. I'm still curious about the easier approach explained in the booklet. Large magnets are expensive...and I may have to fabricate spacers so the claws don't turn.

3 Phase motor controllers shouldn't be a problem, though finding dependable ones is always a challenge.
 

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I dunno about the cheap oilite bearings. The Motorcraft alternator (out of an '85 Ford LTD CV) I have in my hands has what appear to be good sealed-bearing rings on each end of the shaft.


Regarding donut ring magnets, pancake-style radiator fan motors have these, which may well fit inside the claws. I have one with a broken shaft I'm going to re-open and check the magnet dimensions on, to see if it'll fit inside this alternator.
________
Buy glass pipes
 
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