> Even if the revmaster alternator (dynamo) won't work as it
sits, this
> design seems very easy to copy. The RPM issue is not a real
concern
> since the magnets are the only part of the assembly that's
exposed to
> high rpm load. If one were really concerned about
reliability, an
> alternator like this could be constructed at each end of the
engine,
> or two nested on one end, probably even driving by a single
set of
> magnets..
I suspect that the alternator magnetic pickups are divided into
two sets
just like the CDI energy coils. I know that GAMI was working on
an
engine electrical system that electronically combined the output
of two
alternators to provide redundancy(*); there's no reason that
RevMaster
couldn't have copied that concept.
Whoever talks to RevMaster about this beast please ask about
that.
Russell Kent
(*) On the theory that solid state circuits are orders of
magnitude
more
reliable than mechanical drive line parts.
---------------------------------------------------------
Just talked to Joe and he said the coils are in two groups of
five. Two
separate alternators with rectifiers. 30 amps total. He feels it
might go to 7000 RPM
but he will sell just the magnets and stator coils and we can do
our own
carbon reinforced flywheel. He has the magnets cast for that
radius.
He also says the neodymium magnets saturate at 4500 to 5000 RPM
but
there is no real
problem running it higher. You can reduce the saturation by
moving
the coils
radially inward if necessary.
"Neodymium magnets offer the best value when comparing
performance,
size and cost.
They are moderate in price, very strong magnetically, and
typically
allow for dimensional
reductions. They have poor resistance to corrosion and should
have a
coating or
plating applied. Consideration should be given to the grade of
alloy
when exposing
Neodymium magnets to temperatures above ambient room. Neodymium
Iron
Boron has good
resistance to external demagnetization fields because of its high
Intrinsic Coercive
Force (Hci) . This resistance makes Neodymium magnets an
excellent
choice for
electromechanical applications."
Paul Lamar ...No rotor no motor.
Great information. This is a good direction to be going with
electrical
power. Joe sounds like a pretty generous sort.
Paul, is your interest in adding strength to the flywheel driven by
concerns about the added mass of the magnets? How heavily loaded is
the
flywheel without the magnets?
Regards,
Matt-
Yes. The magnets add mass without adding strenght. I think we need to
take
a close look at 7500 RPM.
Paul Lamar
Something else to check for is a galvanic reaction between carbon and
the flywheel.
Carbon will definitely eat Aluminum. I assume to lesser degree steel.
Some people use an insulating layer of epoxy/glass between the carbon
and AL.
Cheers
Cary
Paul,
Have you looked at the after market high-output units for Harleys, sold
by Compu-fire (
http://www.compufire.com/pages/harley-main.html). They
claim 40 amps, 25 amps at idle. The unit has 18 coils. Looks like it
could possibly fit between the vibration damper and the psru plate. The
entire kit sells for $400.
Mark S.
"3Phase Charging System
The Compu-Fire 40 AMP 3 Phase charging systems provide 25 AMPS at idle and 40 AMPS continuously
above 2800 RPM. The unique narrow rotor and stator combination fits Softail/Dyna primary cases and
the voltage regulator bolts on without any frame modifications. The precision balanced vented rotor
keeps the stator cooler in closed primary systems to maintain maximum output under all high current
draw conditions. The large flanged seal spacer provides maximum support for the rotor and the
voltage regulator output is calibrated to 14.25 volts from idle on up."
Wow that is a bargain. More current than Revmaster and way less cost.
It could also fit around the PSRU snout possibly. Then you don't have
to worry about it blowing up at 7500 RPM.
If it will live on a Harley it will live on anything :)
I'll think I will go out there and take a look.
I'll also send them email and see if they can give me the dimensions.
Paul Lamar
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