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wind friend

Newbie

Joined: 01/05/2007
Location: Australia
Posts: 39

Posted: 06:53am 05 Apr 2011

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Just a quick question for the forum.

I've thought about placing 6 neo magnets around a bit of hex bar, and would like to wind some coils to suit. Single phase would be easy. Could anyone give me a clue on how to figure out if there are alternatives (see what I did there) to 1P.

When completed it will be an air core altenator small enough to not have to worry about furling. This was lifted straight from wind stuff now projects. Only looking for a few watts @ 12V nom. to prove concept, then maybe scale it up for a few more watts.

The idea of multi phases appeals so the voltages in any 2 coils can be added.

Thanx

Hans

Tinker

Guru

Joined: 07/11/2007
Location: Australia
Posts: 1904

Posted: 02:13pm 05 Apr 2011

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Hans, you might be better off to start with a 3 phase system, I tried the low power single phase idea but was never very successful with that - 3 phase is actually easier to make.
Start with a ratio of coil numbers being divisible by 3 and magnet numbers being divisible by 4. So I suggest you need 8 neo magnets and 6 coils. There are many other magnet/ coil ratios, some work better than others and there is even a list of which ones are good (in German language) on the net. If you wish I can dig out the url, can't remember it offhand.

There is lots of info at the home page of this site about how to wind coils & how to connect them etc.
FYI, I went down the small air cored alternator track but was disappointed with the outcome, better try to go for a few 10's of watts. Reason being smaller magnets are less powerful but one still needs a suitable air gap for the stator coils. This air gap is then proportionally bigger and with less magnetic force available, making the alternator much less efficient as a result. Its fun but just as much (or more) work to build a small alternator than it is to build a slightly bigger one. Edited by Tinker 2011-04-07

Klaus

Sacredsax

Newbie

Joined: 22/04/2011
Location: United States
Posts: 7

Posted: 05:54pm 21 Apr 2011

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Tinker, what is the link you mentioned above, for the the other magnet/coil ratios. I want to build a 3 phase star config. Also, am I wrong about it being ideal to have more coils than magnets to capture more of the flux field? Thanks.

Jeremiah 29:11

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