2-500w stators or one big stator, power?

[gww]

Flux
Very good and thank you.

To the rest of you that gave answers, Thanks.  Some of you repeted the same thing with differrent ways of saying it.  This is what the uneducated like me need to start to understand.   I always read these post and many times we never get to see what differance the advise given makes when put in to practice.  Sadly it will probly be the same with me as one turbine is one place and the rest are not flying and wont be for some time. I am sure that it will help when I put it all together 17 months from now.  thank you

[gww]

Hugh
I went to your web site and could only find you 2010 edition book.
You mention in you post 2012 edition.  Are you able to post a shortcut in this forum?  If the above is what you were referring to thats fine also I can find it.  I tried looking it up on home page under plans and also under books.  Thank you
PS tried to post picture but as said earlier to dumb.  Kept getting file to large error.
                 blades for unfinnised one

[gww]

New question
Picture of the stator of my second stator for my last 5oow turbine
 stator.pdf (179.9 kB - downloaded 231 times.)
Above Hugh states " The weakness of my 2003 plan is it tends to stall the blades"
I wired this stator with 340 turns gage 21 wire.  The plan called for 320 turns of 21 gage. Shame on me.

It looks to me like there is more room in the stator for more wire.
Now the question;  If I would have used bigger 20 gage and the same turns would this increase the potential to stall.  Not currently planning a change just want to know for future reference. 
Thank you
     gww

PS
How did I get the tubine picture right and the rest as only attachments?  arghhhhh.

[Flux]

If you wind with the same number of turns of thicker wire, if nothing else changes you will stall worse. I would wind with the thicker wire but reduce the number of turns to the specified figure or even a few% less. Almost certainly it will still stall but you can gradually increse the air gap until it runs better. If you reach a state where even more gap is hurting your low wind performance then is the time to add a little bit of resistance in the line.

This does the same as winding the stator with thinner wire but it keeps the heat out of the stator, it is better to have a lower resistance and more robust stator and have any heat generated in the line cables or an external resistor.

I would always use the largest size wire you can get in and still get then required number of turns even if it means adding resistance externally to reduce stall. Always go for an increase in air gap first if it stalls, usually this will correct the problem without having to do anything else.

Flux

[gww]

Flux 
Thank you for your responce. 

I know I may be abusing this post by adding to many topics but here goes.

I built two almost identical tubines and had one problim on both.  I tilted the blades at a slight upward angle making the blades sit alittle further from the tower.  I had an impossible time getting the stator mounts square with the rotor.   When I tighten the stator it seems to bow it slightly.

  In hughs plan that I built it calls for 4 nuts between the two rotors for your gap. On turbine one this worked well enough to get it positioned without rubbing as long as I dont tighten the nuts too tightly aginst the stator.  The second one I had to add two washers to get smooth operation.  This seems to be ok as this was the one I added 340 turns rather then 320 turns that the plan called for.  It is still 6v higher at 60 rpms. first one 17v second one 23 v. at 60 rpm just counting seconds no measurement equiptment.  I find it hard to believe its 6v difference with twenty turns and a larger gap.  Would have thought 3v without the extra gap.

Now for the questions;
1.   How does a guy get all three stator mounts square with the rotor?
2.   When you widen a gap if the coils are closer to one rotor or the other does it affect voltage or does it even out between the wide and narrow gaps?
3. With locktight on nuts and low tourche (not super tight but not loose) will I have a chance of keeping the stators stable in operation?
4.  As I have never built before, I wont really know how the one with 17v or the one with 23 volts will act with the eight foot blades untill I fly them will I?  (48v system)
5.  If the cut in is too low on the second turbine would slightly wider or 8.5' or 9' blades overheat the 21gage wire?
Thanks
  gww

[Flux]

Lots of interesting questions.

If you have full workshop facilities you will have no trouble lining things up but most constructors have to do the best they can with what they have.

If your stator mounts don't line up it is easy to use washers to shim things to the correct position. Hold the stator temporarily in place and see what gaps you need to shim. I wouldn't leave nuts loose, it's better to get the things lined up with washers or thin bits of shim so that you can tighten the nuts properly. If you loctite the nuts they will hold ok but you may get fretting from the inevitable vibration if things are too loose. I wouldn't worry too much on the one you done, but try to get the next one lined up and tight.

When you widen the gap it doesn't matter if the stator is not in the centre as long as it clears the magnets, the air gap is the distance between magnets and the flux there is fairly linear and consistent so having equal clearances is not essential.

With 23v at 60 rpm you will have a low battery cut in about 120 rpm. That is rather slow for a 8ft prop, it may give you good very low wind performance but I think it will kill your output in the most productive wind speed.

You could increase prop size if you are in a low wind area to advantage, up to about 9ft should be safe for the rest of the structure and hub. The main concern is that you can control the thing in high winds without burning the stator. Any increase in prop diameter ought to be accompanied by an increase in alternator offset to keep the furling safe. As you will be running further from stall it will be more lively and more difficult to control so make sure the tail is light to start with and increase weight if it furls too early. If you get regular high winds in your area I would not increase the prop size but increase the air gap and possibly add line resistance to get it out of stall to make it perform properly.

Flux

[gww]

Flux
I am working out of a spare bedroom and on a back patio on a glass table that I already broke the end off clamping blades to it.  Useing hand held tools.  I have a decent set up in MO but not in Indiana.  You have been very helpfull and I thank you.
        gww

PS
I live in a pretty high area for my county.  Cell pone tower across street.  In 16 years treetops broke twice in storms.   normal 8mph or less summer 11mph or less winter ecept storms.  not measured just wind maps zone 2.
thanks

[gww]

I just read hughs wind turbine recipe book and the question that flux so kindly answered about getting my stator mounts square with the rotors is adressed their plan also.

In hughs 2003 plan that I built, three peices of angle iron were attached as the stator mounts using the yaw bearing as a base.  They were hard to get square because I tilted my rotor.  The book has you build the rotor head assembly that is also the stator mount and then attaches the whole thing to the yaw assembly at an angle.  The mounts are square with the the rotor and it is easy to build and hard to screw up.
Very ingeanous.  You guys probly already knew this but maby someone like me who doesn't will read this and have a better machine because of it.   
Thanks
gww