the Otherpower.com Discussion Board || Comments quick update on blades plus question regarding induction conversions

Front Page - [Homebrewed Electricity-- (wind) (solar) (hydro) (steam) (controls) (storage) (mechanical)] - Classifieds - Site News
Everything - Newbies - [Remote Living-- (housing) (heat) (light) (water)] - Rants & Opinion - Diaries - Our Products

quick update on blades plus question regarding induction conversions | 11 comments (11 topical, editorial)

Re: quick update on blades plus question regarding (3.00 / 0) (#8)
by cslarson on Sun Jan 27th, 2008 at 05:05:48 AM MST
(User Info)

Thanks for the warning. Since the idea is to come up with something that will be easier to make I will certainly heed it! I looks like I am back to the original Zubbly design. The mockup below uses 18(dia)x15mm disk magnets. These would be used in the 5.5kW induction motor pictured in my first post. Modeling it makes it easier for me to line everything up and make templates and such. Yes, I will be using neodymium magnets.

So you are saying that I cannot simply use thicker disk magnets to increase the flux and thus increase the final voltage? Does the magnet configuration shown below look sensible?

[ Parent ]

Re: quick update on blades plus question regarding (3.00 / 0) (#9)
by ghurd on Mon Jan 28th, 2008 at 03:44:27 AM MST
(User Info)

It looks a lot more sensible to me.

Increasing the magnet thickness (some people call it 'length') will increase the voltage.

The big thick bar neos looked like it might have saturated the laminations, causing problems. (if you could have got them on there!)
I had the problem a couple times. I can't explain it, but here is where it was explained to me...
http://www.fieldlines.com/story/2006/8/23/144336/344
G-

[ Parent ]

Re: quick update on blades plus question regarding (3.00 / 0) (#10)
by cslarson on Mon Jan 28th, 2008 at 08:08:09 AM MST
(User Info)

Thanks for the link, though I'm not sure how much of it I understood. Is the gist that the laminations in the stator can only usefully take a certain amount of flux going through them? I came across these magnets which are the same cost (by volume) as the 18x15mm ones in the image above, but are 3/4" x 3/4" (19.05mm x 19.05mm), so thicker. Could using thicker/longer magnets like these cause over-saturation problems?

Just one more question if I may. Zubbly's method is to machine down the rotor, and with the help of a pre-drilled fiberglass cylinder, set the magnets in place with resin. Could the holes be drilled straight in to the rotor (though problem might arise getting them all exactly the same depth)? I was also thinking it might be possible to make something that has the same initial function as the fiberglass cylinder that Zubbly uses, but that could be removed to function in the same way for the next conversion, eliminating the need for drilling all those holes again. The problem with the second idea is if the fiberglass is needed for added strength.

Thanks very much for your help. I realize I have less experience with these, but believe there is knowledge here that could help encourage a better small wind power industry here in Afghanistan.

[ Parent ]

Re: quick update on blades plus question regarding (3.00 / 0) (#11)
by ghurd on Mon Jan 28th, 2008 at 08:31:42 AM MST
(User Info)

I do not know when saturation will happen. It just looked like if those big bar neos were installed, it could have been a problem.

I don't think it would be a problem with round neos.

Setting the magnets into the steel rotor will short out the flux.
They could go in a small percentage, but not much.
Many people have machined the rotor, then used a pressed on aluminum cage dilled to hold the magnets. It's something I can't do.

This would work with a lathe, and a lot of time with a file...
http://www.fieldlines.com/story/2007/2/2/55123/75010

[ Parent ]

quick update on blades plus question regarding induction conversions | 11 comments (11 topical, 0 editorial)

Menu

· create account
· How to use the board
· FAQs
· search the board
· Google search the board
· Old Otherpower Board

Login

Make a new account

Username:

Password:

You must be a registered user to post here. It's easy and free, and the link is on the upper right side of your page.
All trademarks and copyrights on this page are owned by their respective companies. Postings are owned by the poster, but may be deleted or moved at the ADMIN's sole discretion. The Rest © 2003 Forcefield.
You can Email the board ADMIN here. PLEASE include the username you signed up with!