low KV motor 1.5KW, cheap and waterproof

another prob is the design of the crank. with a dual freewheel system the BB shaft get way to long for simple implementation
briangv99 said:
On the bike with a Extron kevlar 92T #219 sprocket and adapter -
Picture001.jpg
Click to expand...
 
crossbreak said:
another prob is the design of the crank. with a dual freewheel system the BB shaft get way to long for simple implementation
Click to expand...
If I was doing dual-freewheel on the cranks, I would use a freewheel on each side. Yeah.... not simple...
 
crossbreak said:
i must say, i was already pleased with my second freewheel on the jackshaft/hubmotor. I used a low ratio of about 1:2.3 so the freewheel turned relatively slowly. You just can't feel any drag from it.
Click to expand...
Yes, I think that's the reasonable solution :)

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=35846

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=37224

http://www.bikemotive.com/
 
How does the Wxnaier compare to the brushless currie motor being shipped with gnc kits?
The Wxnaier looks like a mini etek which would seem ideal for an ebike build because it is thinner than any standard motor allowing for an easy mid drive build.
 
The problem with these alternators is, we have not much info about them. Maybe we should work out a Wiki page with available motors capable of 1.5-3kW peak power (if speeded up) to get a better overview. There are plenty of 24V version at http://www.electricscooterparts.com/motors24volt.html which could be used with 36 or 48 Volts and this is not the only source. Problem is, we don't know anything how they compare in efficiency and heat dissipation, when speeded up or used with amps. A test bench with all of these motor would be nice, but who would pay this all?
 
I think Miles alluded to the windings in an earlier post... but no one has raised the issue how to drive this thing... the windings are sinusoidal and so normally requiring sine wave commutation, not our usual 6-step block commutation.

I don't really know the full implications of the mismatch. Maybe just some significant torque ripple? I don't know much about the readily available controllers maybe there are some sinusoidal ones available at a reasonable price? possibly also requiring encoder position feedback (more cost)

rewind perhaps :) or maybe I'm over thinking it!

Dean
 
dm9876 said:
I think Miles alluded to the windings in an earlier post... but no one has raised the issue how to drive this thing... the windings are sinusoidal and so normally requiring sine wave commutation, not our usual 6-step block commutation.

I don't really know the full implications of the mismatch. Maybe just some significant torque ripple? I don't know much about the readily available controllers maybe there are some sinusoidal ones available at a reasonable price? possibly also requiring encoder position feedback (more cost)

rewind perhaps :) or maybe I'm over thinking it!

Dean
Click to expand...

that bit is ok, heaps of our hub motors are sinusoidal, 6 step works good on them, just needs halls i spose.
 
crossbreak said:
dm9876 said:
no one has raised the issue how to drive this thing... the windings are sinusoidal
Click to expand...

how do you hit on this :eek: multi layer winds don't have to be sinusoidal ones per se
Click to expand...

I did not know that, I guess as well as the pictures showing the windings crossing multiple stator teeth and overlapping... I figured it was implied by this actually being a 3phase generator.

toolman2 said:
that bit is ok, heaps of our hub motors are sinusoidal, 6 step works good on them, just needs halls i spose.
Click to expand...

good to know!

I guess I was over thinking it :)

Dean
 
It has to be a distributed winding because there are loadsa slots and only 12 poles. Motors with concentrated windings need to keep the number of poles and teeth as close as possible to achieve a high winding factor.

http://www.emetor.com/edit/windings/
 
dm9876 said:
I think Miles alluded to the windings in an earlier post... but no one has raised the issue how to drive this thing... the windings are sinusoidal and so normally requiring sine wave commutation, not our usual 6-step block commutation.
Click to expand...

From what i've read, you can drive them with a block controller just fine.. they do end up being noisier.
Maybe the efficiency goes down some? I've not heard of any tests on the issue.
 
I did end up finding some good stuff on the topic

http://www.magnelab.com/uploads/4c51d9ba6fe5a.pdf

page six shows some simulations with the different motor and commutation combinations.
 
First chapter of this book is a good place to start:
http://books.google.co.uk/books?id=gbIDM60AvGAC&printsec=frontcover&dq=hughes+austin&source=bl&ots=z8WEN0JSOq&sig=o23-2rRxic25mnvuBnh-mmV-Arc&hl=en&sa=X&ei=fhhHUMW6C6qN0wXGw4GIAw&ved=0CDAQ6AEwAA#v=onepage&q=hughes%20austin&f=false
 
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