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

[gww]

First post.  I am on my second build of hugh piggott 2003 version 8 foot blade wind tubine.
what would my power have been if i would have put the 20 coils and 48 mags on one stator and two rotors?
 more or less?
 thank you. 

[DamonHD]

I am NOT a wind expert, but:

1) The power available from the wind is your limit, so all there is left to argue about is efficiency of extracting it.

2) This has been endlessly argued and I think the consensus is that a well-built single stator will do as well as anything, but I stand ready to be corrected.

3) Welcome!

Rgds

Damon

[gww]

damonhd
thank you for your responce.
   The reason I ask is I read this on a differrent post the consenses was; double stator wasn't as good as bigger stator (or two wind turbines?).
  same magnet size and coil size bigger rotor and blades. if 1000w seperate how much combined?

PS can't get spellcheck to work.

[gww]

Am I correct in my turbine that the ten coils at 320 turns of 21ga wire is giving me 48 volt per coil, wired in parrellel, with the individual coils providing the amps combined?

with bigger rotor, more of the same coils and bigger blades,  wouldn,t this slow the rpms and not reach cuttin?

Thank you

[fabricator]

You are going to have to come up with a more meaningful post than that, that means pretty much nothing.

[gww]

fabricator
I thought it was a clear question.
  Do I understand my own turbine and if I do and used the same coils and magnets that I built two with and made only one 48 mags twenty coils what would it give me?
  I have been tinkering and trying but wont say I understand. 
will say I have looked at many of your post and beleive if I could state it correctly you could help.
thank you

[Watt]

Is this a 3 phase machine you have?

[gww]

would like to say I have been reading every post under wind so far to page 11 and know quite alot of what is said is over my head.
  my experience is putting magnets in ceiling fans,  one geared up leason motor that bent my pole double,  one 6 coil 8 mag hugh desine on car bearing with wire and mags from ten microwaves,  have a fisher paykle washer motor and these two 500w tubines. 
all with ideals off this and other websites. doing my best and will take any help I can get. 
thank you

[gww]

no twelve mags each rotor ten coils

[gww]

My typing is slow. Two 12 mag rotors and a ten coil stator.

[fabricator]

Are all ten coils wired together in series? The end of number one connected to the start of number two etc? So you have just two unconnected wires when they are all connected?

[joestue]

I read this on a different post the consensus was; double stator wasn't as good as bigger stator (or two wind turbines?).
  same magnet size and coil size bigger rotor and blades. if 1000w separate how much combined?

True, double the diameter and you double both the number of magnets and the number of coils, giving you 4 times the voltage because the tangential velocity doubled as well

Doubling the diameter will to do nothing to increase the amount of current.

however, doubling the diameter is going to pull (8?) times as much air though the machine, so if the thermal limits are primarily insufficient cooling, rather than insufficient thermal conduction then you will be able to pull more current out, probably 50% more perhaps.
However, this is very dependent on the thermal conductivity of the epoxy, and how thick your coils are.


as with all wind turbines, the challange is preventing the turbine fro

[gww]

no  The coil starts are all connected and the coil finnish goes to 5 rectifyers.  two tubines built this way.

[gww]

joestue
tangentiel velocity?  speed of magnets further out on rotor, faster at slower blade tip speed?

[gww]

stator half inch thick.

[gww]

fiberglass resson from auto parts store for encapsulent. Lots of baby powder added.

[fabricator]

no  The coil starts are all connected and the coil finnish goes to 5 rectifyers.  two tubines built this way.

Do they make power?

[gww]

fabricator
open voltage free spinning on a short test stand has got to 100 volts, lights a lawnmower light quite easly by hand. 
Slams to a stop if shorted.
They are not in the air yet as I am living in a different state "due to work" and have 18 months to go before retirement.
Then I can move back home.
 I have 2000 w solar panels (homemade), duel outback inverters and asessories, morningstar 60 charge controller and no batteries yet. 
Nothing hooked up yet due to only 5 weeks vacation per year.
I have spent a lot of time reading forums but this is the only one I have joined.
I will probly abuse you guys with questions so thanks for yours and any response.

[joestue]

faster at slower blade tip speed?

at constant rpm a doubling of the diameter quadruples the power.
if the rpm drops by half because you doubled the diameter of the turbine, then you've got to account for that.

[tecker]

Post some Pictures with the run out on your gensrets into the battery banks

[gww]

tecker
My house is in MO.   
For the last two years I have worked in Indiana.
  In MO I have two lawn mower batteries and one car batterie hooked to my six coil eight magnet per rotor twelve volt turbine with morningstar charge controller and hot water heating element diversion laod on a sixteen foot tower surrounded by trees.
 Put it up in april. 
probly lossing power just by having controller hooked up.  sealed car bearings are too stiff and it takes a stout wind too turn it.
   The  outback and other equip. is just setting there and here due to lagistics.  I only have three pictures on my phone (not a smart Phone).
 Cant spell and cant type but can read, too dumb for the rest.

[gww]

Joestue
 thanks for the post.
 two 12" rotors  Ten coils 50v ea one amp each at 165rpm =50v ten amp = 500w.
  question;  two 24" rotors twenty coils wired parellel, magnets moving at the same speed over the coils as 165 rpms make them move above, what would be the new rotor rpm.
  also 21gage wire (thin) or extra air flow which would limmit the heat affect of the power?
thank you

[tecker]

I see you have to stay on the job . You want to keep the Two rotors instead of the One large rotor . You have the stators wired for 48 . I'm not sure about 10 amps constant from 21 it seems a little hot . Chassis wire is around 9 amps so you may need to hold it down to 6 or 7 . I'd say you have what you need with the solar and the two gen sets pushing in 12 to 20 amps at 50 volts . I like having multiple gensets myself .  The two probably will not have problems at the same time you just need to get up above the trees.

[gww]

thank you tecker
last question.
If I were to build again, the cheapest ($7) neo mags i could find were n42 2"x1"x.05.
For a 48v turbine using heavy wire, more mags, what would be the biggest rotor, blade set up (power?) that I could reasonally exepect these mags to handle using dual axial flux desine?
The 3"x1.5"x.75" mags used in many plans are just so expensive.

[scoraigwind]

First post.  I am on my second build of hugh piggott 2003 version 8 foot blade wind tubine.
what would my power have been if i would have put the 20 coils and 48 mags on one stator and two rotors?
 more or less?
 thank you.

My 2003 plans are out there for free download but they are almost ten years old and my new 2012 recipe book is much better.  If you can't afford to buy the paper edition you might consider the Kindle edition that is only $5.

I have read this thread but I can't figure out what is going on I am afraid.  Putting two alternators on one shaft can given you double the power (double the current) whereas putting the same magnets and coils on a single bigger alternator an given you four times the power (double current at double voltage) for the same loading on the coils (heating effect).  Efficiency would be higher due to higher power out in relation to losses.  Or you can run this at lower speed.

What I can't understand is where you are going with this. Maybe I am not a patient reader but I often get lost in a load of details on this board and end up totally confused.

What I will say is that it's essential to have a good match between blades and alternator.  The weakness of my 2003 plans is that the alternator only really matches the blades well in very low winds and then if the wiring is good it will stall.  The Recipe Book describes a whole range of well matched alternators and blades.  It also describes how to calculate the alternator performance, and match it to the blades.  The process is very reliable when you are working with the same magnets and the same coil geometry all the time.  I also help people to design alternators for given blade sizes by email.  But I am not sure how to help here as I can't follow the drift.  sorry. 

I hope this helps.

[Flux]

I likewise have only just seen this and find it totally confusing.

Personally I think there is confusion between what is ideal for an alternator and what is required for a satisfactory wind turbine.

There is only a limited amount of power you can extract from a given diameter turbine blade in a given wind condition. If you change the alternator you change the blade requirements and mess everything up. If you use more magnets then inevitably you need to extract power at higher wind speed or increase the blade diameter.

Large rotors have to run al lower speed in a given wind so you are faced with the problem of extracting more powwer and doing it at lower speed. The things interact so badly that you just can't consider individual changes to an alternator unless you have some mppt scheme to maintain the match.

Working designs by Hugh or the Otherpower folks have matched the alternator to the blades and obtained a good working balance. Any messing about with the individual parts without a full understanding of the consequences will invariably prove disappointing even if you actually manage to make an improvement to the alternator.

In terms of power out from a given set of magnets and a given amount of copper you will do much better with one large diameter machine compared with two stacked smaller ones, especially when you consider the reduction in speed required to use larger blades but this is pointless if in the process you mess up the match between turbine blade power and alternator loading.

Some of us have been investigating these things for many years and still have not reached a final conclusion but have reached a point where we can design something that works well enough. I fail to see why people starting from scratch with no experience still get caught in this issue of trying to perfect an alternator and upset the match to the blades and end up with something that works so badly . Start with a published design, build it and make it work, when you understand how it works you will be able to introduce changes to suit your materials . facilities and wind regime and if you are lucky it may be an improvement. if you make it worse then you have not understood how things work.

Some of have been offering advice here for many years, the information is still on here somewhere, it becomes a bit tedious finding that people are still muddling through having to be different and trying to run before they can run.

Flux

[gww]

Hugh
hello
I am on my third build of one of your free plans.  I guess I am a cheap skate or I would have not taken 10 microwaves apart an built your 6 coil, 8 coil ferrit mag plan.
  Some of my uncles collect scrape metal. 
I had to move for work and the last one I built cost me $1200 counting some tools cause I had to buy more stuff since I couldn't scrounge from them.
I guess its not all the money.
I read many excerpts from you book and it seemed way over my head with alot of math and so I just jumped in without it so the mastakes are mine..
When deciding the last builds I couln't decide on you plan of othepowers 10 foot plan.
I built yours.
I'm thankfull that you put it out there or I may have never did anything.
I only have one flying and I'm not by it to watch it.
I may not build any more untill I get that opertunity (17 mo. from now).
I will buy your book as I am understanding more the I did now that I have played with the math on your 2003 plan.
In your post you answered the question I ask in a way I could understand.
Blades?  I have built three sets with standard cheap pine boards.
two sets 5.5" cord and one 7.25" cord with. I hate carving.  I put one set on the 6 coil 8 pole turbine. 
I swithed the ferrets for neos and it seams to stall on twelve v. system.
Were no blade portion of that plan.
These are all seperate turbines.
  Only stator, blades and metal work for the last one but not welded up yet.
  I just wanted to understand in case I got the bug and did build anouther.
  Help with better blade to match the stator that I already have would greatly thank you for.
your putting it out there still makes you a hero in my mind.
Thank you
  gww

[fabricator]

I'm glad I'm not the only one who was completely baffled.

[fabricator]

BTW, I for one am extremely glad to see Flux posting here again, I don't know if he realizes it but he is like an anchor to reality on this board.

[Flux]

Gww
You have basically already found for yourself the problem of changing things in a design. The ferrite alternator will not be improved by changing to neo without serious other changes to the machine. As you found it will stall very badly if you substitute neo magnets.

The same thing will happen by doubling up on stators or using more magnets on a larger diameter.

If I remember correctly for that Project Hugh only designed the alternator, I believe there were two sets of blades designed for different wind areas but they were built from fibreglass and not carved wooden blades.

I think you would benefit a great deal by using Hugh's later plans as these cover all aspects of the machine and the blade plans will match the associated alternator design. Now having had some experience I am sure you will follow the maths associated with the later designs a lot easier.

Great that you have been inspired to get something working.

Flux

[gww]

Flux
It is probly my confussion that confusses you.  You may have miss read my intentions for posting these questions. One doesn't always know who to trust.  One time I paid 40 bucks for an earth for energy plan only to find it was full of thing taken off the internet that I had allready looked at for free.(scam?)

As for following plans, I have no imagination so I have to have plans.  I cant say I have never substituted items in plans because of sloppyness, finding matiereals or cost.  I have never thought I was improving them.  I was just hopeing to get close to what might actually work.  Examples of this are;  wires and mags from microwaves, Chrysler front wheel bearing.  Even while doing this I picked hughs ser lanka plan which used simular mateireals (ferrit mags).  I followed muddymud on ceiling fan convertions, Anton wind for the leason motor and Hugh Piggot almost to a tee on these last two.  By the way I have not found bigger rotor plans for the mags I am useing, only otherpowers 17'-20' tubines using mags that cost ($28-$50).  I dont even know if I will build more turbines.  I just wanted to try and understand (compare mine against) incase I desided later i wanted more.  a guy can only put up so many towers.  might want to change or replace one someday.  I live in a poor wind area which regulate this to an exspensive hobby. When I moved to indiana i gained almost 2.5 hours a day less drive time and was bored out of my mind.  I made solar panels and wind tubines.  I would still like to do the best I can with them even knowing full well my low wind probly makes it not worth it.  I am still proud of what I've built and its been interesting.
Hughs 2003 plan had math that i am starting to understand.  I have read many of your post and you have a tallent for communicating that almost breaks the imformathion down to the level that a guy that did terrible in school (me) can understand. (almost).

I Find that getting a plan and jumping in with both feet helps me understand more as I go along even if I make mastakes that could have been avoided. Got to know what you are looking at before you reconize its a mastake.  watching others has save me so mastakes. 

Hugh breaks down imformation well also.  I am going to finnish my last Hugh build and with backsheds help Im going to finnish a fisher and paykel build and learn for when one of my tubines fails or i get ambitious what i might do next.  Im going to try Hughs book and bother the hell out of you guys for as long as you will respond.  To show your imprestion of me is somewhat right  I wound 320 turns for the first stator (plan calls for 320) and 340 for the second one.  Hugh just posted above that the blades stall a little at 320 so now Ive probly made it worse.  Oh well live, learn and adjust.

Well youv'e read my post and by my reading alot of yours, I trust your guidence even if it proves I dont know crap, if you will give it.  By the way I believ I understand With Hughs answer above what i was asking.  With his plans math I might even get some where on blade sizing.  Now can I adress posible blade stalling on my current build?

17v-20v open voltage turnning by hand at aprox. 60 rpm.  This is for a 48 volt system. Add resitance, air gap and or bigger blades?

P.S.
I didnt see any blades in the sir lanka plan and the 2003 plan had great details on tsr 7 wood blades.

My original post was I read the responces to a double stator post and wanted to learn more including compaired to what I did also.

I put the neos on the old ferret rotor cause I had to take it apart  several times due to shoddy workmanship.  My first turbine (learning curve) I got better and went back and redid it I was home on three week vacation and it was the only game in town.  also did a bathroom.

Better?  I still have the tubines I have already built.  I should atleast fly them before they hit the trash bin.  I may never build anouther if it takes me ten years to get towers, batteries, inverters and solar racks all set up and running.  Then again I have 17 months before I can retire and move back home.  I might get bored.
                Thanks

[gww]

Hugh reread your post.  Did I understand you saying "good wiring"  are you refering to wiring to the battery?  In other words 12 ga instead of 8 ga.  as your plan says this will help stalling with the plan blades?  By the way very neat way to wire stator.

[Flux]

Thanks GWW that makes a lot of sense. When I think of plans I think of Hugh or Otherpower or similar. Not having a need to scour the internet for things I tend not to realise that there is a lot of total crap out there mainly with the intention of extracting money. If you have been looking at some of this stuff then my comments were not vaild as some of those are not working schemes anyway.

Back to your stalling neo generator, it was intended for ferrite blocks ( fairly thick if I remember rightly) using microwave magnets would probably make it rather weak and it may have been too fast. Changing to neo has pushed the thing the other way. I believe the intended blades were about 7ft and a cut in of nearer 200 rpm would be near the mark. With it down at 60 rpm you will hard stall at 12v and it will be miserable.

If you have the option to change to 24v it will work much better but probably still stall. If you need to keep to 12v then you can increase the air gap to drop the magnet flux down to that of ferrite but it will be a big gap and you waste the benefits of neo but the performance will be similar to the original.

In this case I would not add line resistance, that trick works if you have the cut in right and it stalls in high winds, with the cut in too low it will add more loss than you can tolerate.

For a low wind area you can gain a lot with bigger blades but all depends on the rest of the mechanical construction and how it will hold together. Car hubs should be good for up to 9ft or 10ft with care but the rest of the head gear and tail etc may need significant changes.

You could try delta connection if the coils are star at present or you could connect the coils in parallel instead of series ( make sure you get the phasing right or they will cancel).

Delta and parallel windings will lead to circulating currents which are far from ideal with low wind operation but the gain may still be worthwhile. One way round this problem would be to rectify each coil with a bridge rectifier and connect the dc terminals in parallel. This may be a very good first move if you can tolerate the rectifiers up on the turbine.

Connecting as described with individual rectifiers and a bit of increase in blade size say up to 8ft would most likely bring this thing to life in the low winds. If it still stalls in high winds then is the time to add a bit of resistance but if you are doubtful of your cable run then that may be enough to do the trick without adding anything.

I am sure that with a decent wooden prop to Hugh or Dan's plans and the thing re-connected with individual rectifiers you would have a very good 12v 8ft turbine that bears no resemblence to it now in hard stall.

Flux