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Stator material

PostPosted: Sat Dec 08, 2007 5:35 am
by conntaxman
What is the best material to make a stator out of?Could it be made of wood with the coils epoxied to it.Next steel.
I am making a vertical wind turbine,and plan on 12 Neodymium magnetics and 12 coils.3 phase.
thank you
Johnny

Re: Stator material

PostPosted: Mon Dec 10, 2007 6:10 am
by windgat
Hi Johnny. I use Versamid epoxy resin, which is designed for use with motor/generator windings. I suppose wood could work, although the coils can get hot depending on the current and wire thickness. I guess you plan on one rotor? For two rotors (one each side of the stator) the wood may take up too much space.

12 coils and 12 magnets? That doesn't sound right. How will you get three phase out of that?

Re: Stator material

PostPosted: Fri Jan 18, 2008 5:11 am
by conntaxman
hi windgat. YOu are right,I made a mistake when I said 12 mag,and 12 coils.should be 9 coils.
How would this work.24 magnets and 18 coils on one disk.I know that is the same as useing 2 disk.I think that I just answered my own question.
I just got my magnets in [and they are strong] and now am thinking of what hub to make it out of. Think that Ill be useing the same type that they use in a trailer.[Stub axal]
so now the fun begins.
See all you guys later.
Johnny
oh and
Good luck to all, building.

Re: Stator material

PostPosted: Fri Jan 18, 2008 6:22 pm
by conntaxman
Would like some input. Im making a Savonius type [vawt] Seeing that these are low rpm but with very much torque . I was planning to build a 12 inch stator with 12 magnets and the feild with 9 coils for 3 phase. That is fine. If these are low rpm couldn't I build a 37 inch stator with 36 magnets and the feild with 18 coils.Each coil wound to produce about ??????????? and wire them in seris or parallel??????? .To gain the low rpm with that much torque. The size of my Savonius will be 60 inches in Diameter and 48 inches tall, or 24 inches tall. It will have 6 vertical veins each 30 inches wide and the radius of the veins about 150 degrees. I could be off on the 150.
Any ideas,,,,,,,,,,,,or comments..........
I will be useing this to charge 12 volt batteries.
tks
Johnny

Re: Stator material

PostPosted: Mon Jan 21, 2008 11:51 pm
by windgat
Hi there. Sounds interesting! The voltage at a given rpm depends mainly on the magnetic flux (= distance between the magnets and magnet strength), rotation speed and number of turns per coil. You haven't given figures for any of these - not that I would know the analytical calculation method if you did, but that's certainly the place to start! Maybe if you give these figures I can compare to what I have done and make a guess at what voltage you might get.

I can't see any problem with using more magnets and coils as you describe.

Re: Stator material

PostPosted: Fri Jan 25, 2008 6:06 am
by conntaxman
windgat ,I just made a very small proto type of a vawt.Useing different kinds of blade [vains] set up,and styles [curved and flat] 2 ,3,4 blades.The blades are only 4 x 4 inches tall and 4 " tall x 6" wide ,with a very small fan that creates ABOUT a 7 mile ahour. It seems that I can get about 50 RPM out of this.Mostly the 4 blade with a full curve with about a 6 in radius.
I can't use a propell type because of zoneing. ha ha ha,these people get ya.,So I want to do it under the Radar.LOL. so what Im thinking of is going to look like a Hot air furnace blower fan. I could mount this on my roof of my work shop and no one will know what it is. ha ha ha
The diamitor will be 8 foot, hight really don't know yet, about 2 or 3 foot tall. Now the amount of virtical Vains it will have, Didn't figure that out yet either.It seems that too many Vains will make it go slower.The vains will be made out of Gal. sheet metal about 21 gage.
Rotor and stator. humm. Once one person told me that I needed 2 Rotor's and 1 Stator to make ac. I thought that you can have only 1 rotor and still make ac.
So my thoughts were to make the ROTOR twice as large in Diamitor and also the stator.So in one revalution it would put out twice the amount of ac ,at a Low rpm.
So the rotor would be either 24 or 36 magnets [1"wide 2"long 1/2 " thick with a pull of 78 lbs
or 80 lbs each.]
I think it would create the same amount of ac as the 12 magnet double rotor. But with less resistnace.
The windings pre coil for a 12 vdc system I think are about 35 turns pre coil about 14 gage.
Would like Any comments,,ideas,, thoughts,, calculations,, free money.
Tks Johnny

Re: Stator material

PostPosted: Sat Jan 26, 2008 4:59 am
by windgat
Hi Johnny. You seem to have done some good testing, great! And good luck with under the radar stuff - I think as more people do this it will build momentum to have regulations changed.

It sounds like you tested with no load? If so that would give far higher rpm than you will get with some resistance e.g. from a generator. The question is not how fast can it turn, but how much power (force x speed) can it output. So maybe do those tests again with something braking the rotation.

Of course you can generate AC with one rotor (if you manage to figure out a way to generate DC directly let me know!). Two rotors create much stronger magnetic flux, and so potentially more power.

Why do you say 'less resistance''? Is that because of one less bearing? Or less magnetic flux and therefore less current generated (and therefore less resistance)?

I suggest you make a rotor, place the magnets (they should stick fine at low rpm without anything to keep them in place), make a single coil with maybe 10 or 20 turns and spin the rotor by hand to see what voltage one coil gives, per turning per rpm, which I have found is linear (see my Benchtesting page). Then its easy to see how many volts you will get from the planned number of coils.

P.S. I don't want to be vain, but it is spelt 'vane'... :)

Re: Stator material

PostPosted: Fri Feb 01, 2008 6:06 am
by dman
hey guys need some help. I'm extremly new to wind power and i'm having trouble with just the basics i'm comfused on how the phases work. and i dont understand when making the coils, are they all made from one strand of wire wrapped over and over? do all the coils go clockwise or do they alternate? and a lot of these pictures i see of assebly look way out of my league i can't weld of fabricate. I would appreciate any info on how to get started on my first project.

thanks

dan

Re: Stator material

PostPosted: Fri Feb 01, 2008 9:45 am
by windgat
Hi dan-man, welcome! There are many ways to do things... in my system I use one strand per phase, which is three coils. Many people use one strand per coil (called 'one in hand') and join the coils after assembly. Some times its 'two in hand' to save time when making the coils, or to get effectively thicker wire. All the coils go the same way - it doesn't matter which way.

How to get started... are you in Cape Town? You could come see what I have done. I also have made a few spare brackets, which is the welding part, and we could make a plan to get you one of those. If you wanted, I could also make a stator (the coil part) for you, as that is probably the most complex bit. Then you would need to do the rotors with magnets, the blades, and the mounting pole.

Re: Stator material

PostPosted: Fri Mar 07, 2008 5:43 am
by conntaxman
Hi windgat
I have my VAWT build and its working in very very low wind,you can barley feel the wind on your face and its turning about 20 rpm per min. here is the link to see some of the pic that I posted on that site DYI. http://www.instructables.com/id/DIY-1000-watt-wind-turbine/
The alternator will be with the 12 magnets, 2"long x 1"wide x 1/2 " thick about 70 lbs pull i think. I been looking on the net and one guy made his windings with I think #20 wire and about 200 turns for about 30 rpm. Sound right to you?
Just cant wait for a good wind to come along. ha ha ha .
It sure is alot of Fun building.
Johnny

Re: Stator material

PostPosted: Sat Mar 08, 2008 9:49 am
by windgat
Hi Johnny. I looked for your post on that site, but couldn't find it - can you give a complete link? I have just enabled 'Upload attachment' for you on this forum, so maybe add a photo here?

Great that it turns in light winds - satisfying isnt it to see it work! Of course, measure is how much force it has when the magnets are in place and resisting the turning... Where did you get the magnets?

AWG 20... lets talk metric, so that is I think 0.8mm diameter. That is quite thin - what is the max current you are planning to have? Then maybe rig a test circuit to deliver that current from a battery, and see how hot the wire gets... or if it melts!

Re: Stator material

PostPosted: Thu Mar 13, 2008 4:28 am
by conntaxman
Hi windgat. I guess they took down the pictures from their site.So I put them up on my site ,here are the links.
http://www.ctsolarenergy.com/images/2turbine.JPG
http://www.ctsolarenergy.com/images/1turbine.JPG
My site is
http://www.ctsolarenergy.com
Im doing a little modification to the vawt,Im going to do away with the Fram work and just use a 2" sch40# pipe.If you can picture from the ground up a peice of 4 inch round pipe about 17 feet,then at the top of that Ill have a plate of steel about 2 feet long with a 2 3/8 pillow block at each end of the 2 foot plate. These will hold a peice of 2 inch pipe about 5 foot long,and Ill attatch the 3 blades to the 5 foot pipe at the top and at the bottom will attach the alternator.I forgot to mention that on the 2 foot plate I will weld a 7 inch stand off so each pipe will be about 7inches away from each other ,this is done because the rotor's are 12 inches.
Now in just a slight breeze it will turn about 20RPM and with about 30 mph wind it spins so fast you cant see any spaces between the blades.
For the alternator,Im going to end up useing a pr of car disc rotor's,and they are 12 inches in dia,and I welded a 2 inch pipe coupling in the center hole of the car rotors. Im going to put a running thread on the main shaft of the wind turbind,thats the 2 inch pipe,Ill run the thread up about 12 to 18 inches,.so then I could take the first car rotor and SCREW it on and up the main shaft [2" pipe] to the top of the running thread.Then I will put on the stator plate under the 1st rotor, Last I will take the 2nd rotor and SCREW it on the 2" pipe.
Adjusting the gap should be easy,Just Screw the rotor's up or down the 2 inch pipe.
I think.....hope it will work.
I hope 12 inches will be far enough away from each of the rotors so that I can screw the 2nd one on.
Im going to try to make my coils cut in about 20 RPM. Ill be charging 12 volt battaries.
First Ill just a deep cycle boat one, and if all goes well Ill get the LARGE Golfcart or jittney.
Anyways its all fun.

Re: Stator material

PostPosted: Fri Mar 14, 2008 4:28 am
by conntaxman
hi windgat
here is another link for some pictures,
http://www.instructables.com/id/Build-a-Savonius-Wind-Turbine-or-VAWT-to-make-elec/
,
and I will post some pic of a NEW way that I have made for the alternator.Instead of the so called JACK SCREWS. and it is so easy.
Ill post those soon.
Johnny

Re: Alternator and Stator material

PostPosted: Fri Mar 14, 2008 6:05 pm
by conntaxman
here are some links for the Alternator.

http://www.ctsolarenergy.com/images/alt.JPG
http://www.ctsolarenergy.com/1images/alt.JPG
http://www.ctsolarenergy.com/2images/alt.JPG

Im making my alternator a diffrent way,and I Think that Ill beable to adjust the space between the rotors and stator plate very easy.Just by turning the rotors on the threaded 2 inch pipe.
Let you know how it works with the magnets on. Threads are 18 inches long.
Johnny

Re: Stator material

PostPosted: Sat Mar 15, 2008 4:49 am
by conntaxman
I seem to put in 3 bad links.Here are the good links to see the alt.
http://www.ctsolarenergy.com/images/1alt.JPG
http://www.ctsolarenergy.com/images/2alt.JPG
http://www.ctsolarenergy.com/images/alt.JPG
cant waite till I build the alt.
Johnny

Re: Stator material

PostPosted: Sun Aug 16, 2009 9:56 am
by basiedp
Hi all. Just to show what is going on in PE. These coils were wound on a homemade winder. The material for casting was gps resin, cheap. If all the tests comes out to the correct figures the coils will be casted in apoxy resin that's much more in cost.
The magnets used for this unit, 24 off wedge magnets. :thumbup:

Re: Stator material

PostPosted: Mon Aug 17, 2009 11:07 am
by windgat
Looks good!

Re: Stator material

PostPosted: Fri Jul 16, 2010 2:48 pm
by bacharoo
Hi Basiedp,

I really like the finish of your stator. What did you use for you outer ring that contains the coils and epoxy?

Cheers,
Waz