Author Topic: Test alt stator #1 of 3.  (Read 2863 times)

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Jerry

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Test alt stator #1 of 3.
« on: February 18, 2006, 04:54:30 AM »
I wound 3 coils 200 turns of # 24 gage wire. I placed them in the stator and glued them inplace with epoxi.


I also wound a 100 turn coil of 21 gage wire. Its surprizing how much larger 21ga. is then 24 ga.


It was dificult to get the 21 ga. coil to fit the same hole as 24 ga. but I think I can make it fit.


Heres a few pix of the first test alt stator. 2 more test stators to build.  








You can see the wires come out some small holes I've drilled in the side of the plexi stator forms.


The glue is still wet. I'll take the clamps off tommorow and take another picture then.


                              JK TAS Jerry

« Last Edit: February 18, 2006, 04:54:30 AM by (unknown) »

domwild

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Re: Test alt stator #1 of 3.
« Reply #1 on: February 18, 2006, 12:20:10 AM »
Jerry,


Thanks for that. Is that now alternator #30? Have you fixed up your storm damage? Good to see you are persistent!


Keep up the good work!


P.S.: Have looked at your pulse charger idea and I like it!

« Last Edit: February 18, 2006, 12:20:10 AM by domwild »

zap

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Re: Test alt stator #1 of 3.
« Reply #2 on: February 18, 2006, 08:22:12 AM »
"The glue is still wet. I'll take the clamps off tommorow and take another picture then."

It seems many on this board are stuck on epoxy. Not criticizing but just wondering why more people don't weld when using plexiglas and acrylic. I use to prototype with plexiglas quite a bit and love the near instantaneous bond and clean look.

« Last Edit: February 18, 2006, 08:22:12 AM by zap »

Jerry

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Re: Test alt stator #1 of 3.
« Reply #3 on: February 18, 2006, 10:24:54 AM »
Hi domwild.


I'm not sure how many alts that is. For the 14 I've had flying at the store and the 7 I've had flying at home. Theres probobly been another 30 alts  built as test units or expiriments.


I think it will be next fall befor any of my small wind farms are back up to full team stringth?


                   JK TAS Jerry

« Last Edit: February 18, 2006, 10:24:54 AM by Jerry »

Jerry

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Re: Test alt stator #1 of 3.
« Reply #4 on: February 18, 2006, 10:33:17 AM »
Hi Zap.


Sorry about the epoxi thing. Unfortunetly I have very littel knowledge of plexi or other plastics in terms of fabrication or bonding.


I wanted to build a small test alt in a short time. This littel unit is only for testing and not for outdoor or long term use.


So I've simply used materials and skills at hand that would make this littel project hapen as soon as posable.


If you could expand or elabirate on plastic welding this information would be very usefull in future projects use plastics.


Thanks for shareing the knowledge.


                      JK TAS Jerry

« Last Edit: February 18, 2006, 10:33:17 AM by Jerry »

Jerry

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Re: Test alt stator #1 of 3.
« Reply #5 on: February 18, 2006, 10:45:59 AM »
The first stator (#1). is done. Now to wind and glue the other 2.


The center hole in these coils are the same size as the mangets. I now there has been some discsion on coil center holes relitive to magnet size latley but I think this sizing is acceptable.


Heres 2 pix of stator #1.





                      JK TAS Jerry

« Last Edit: February 18, 2006, 10:45:59 AM by Jerry »

electrondady1

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Re: Test alt stator #1 of 3.
« Reply #6 on: February 18, 2006, 05:08:46 PM »
jerry, just caught your comment on samoapower's post . i for one am not tired of  the debate you have triggered with the jerry rig concept.i don't understand the lingo the experts speak.and usually lose track when alot of abrieviations are used( hey , it took me a month to figure out what mpp stands for) but i just keep rereading untill it becomes clear.  at one point i thought you had given ground but i am happy to see you continue in the experiments. i spun 72 coils last week, the stators there for are on hold untill after the smoke clears around jerry rigging.  just one more thing, i bet tomas edison thought he had it all worked out until mr. tesla showed up! everything changes, all the time.
« Last Edit: February 18, 2006, 05:08:46 PM by electrondady1 »

Jerry

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Re: Test alt stator #1 of 3.
« Reply #7 on: February 18, 2006, 09:21:03 PM »
Hi electrondady1.


Thanks for the encuragement. There is a posability I could be very wrong.


I would not want you to change a design or project you have in the works because of my unwillingness to accept proven design that I myself am not convinced of.


My verbal arguments have gone noware. My examples had no impact. My car alt examples were deamed unfair to the star conection.


We'll see if the small test alt will shed any light on the subject.


I'm not trying to stir contraversy. I just have conviction to what I belive is a more eficient way.


If I'm wrong I'll go quietly to the corner and put the dunce cap on.


Again thanks for the kind words.


                       JK TAS Jerry


 

« Last Edit: February 18, 2006, 09:21:03 PM by Jerry »

zapmk

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Re: Test alt stator #1 of 3.
« Reply #8 on: February 18, 2006, 10:56:17 PM »
Jerry,


Ether right or wrong does not matter, Because if it

wasn't for the creative thinkers and tinkerers,

we would all still be living in the stone age !


Looking forward to your testing, and keep up the good work.

« Last Edit: February 18, 2006, 10:56:17 PM by zapmk »

oztules

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Re: Test alt stator #1 of 3.
« Reply #9 on: February 19, 2006, 12:07:36 AM »
On the contrary Jerry


"My verbal arguments have gone noware. My examples had no impact. My car alt examples were deamed unfair to the star conection"


Your arguments whilst not having yet changed the world, have opened up the world to other possibilities. Some have tried similar systems before, but nowhere have i heard anyone deliberatly derating their wire size to half the capacity and doubling the turns.


This just may turn out to be the master stroke. I have learned a lot just by having to confront your ideas, some of which seemed convoluted, and maybe to me factually misbased in some cases, but even if your reasoning was based on some misconceptions, they were based on what you had observed. This made your conclusions far more worthy of consideration.........and the jury is still out!!


I hadn't realised that delta had 1/3 the resistance of star and thats without paralleling your windings. (thanks peter netherlands).


This fact alone deems your system to be looked at for longer. As you know, i have a few powerful three phase machines which I had to convert to match my phase converter, this led me to have to learn about them. It occurs to me that half were star, half were delta. The biggest ones were delta.  It seems anomalous that they would deliberatly use inefficient means to power industrial equiptment. Its not toy equiptment, it's designed to run all day every day. Surely economies of operation were uppermind in the designers minds. You couldn't sell a big delta motor of 10hp for heavy going continuous use if it was going to be much more economical to use a star winding, and you certainly wouldn't design it into your equiptment unless the competition was just as silly. In these big machines, daily cost of ownership is a big issue, it would have to have been taken into account .


This has bought into focus just how much more efficient is star supposed to be, and why?. The fact that star is in use in this axial flux, may have more to to with hughs original testing Was he  trying to get maximun wire thickness into a fixed size area. The logical choice is star, as max voltage for min turns are possible. Once running and seeing lowering of power curve as speed went up, switched to delta, and made comparisons. I don't know, but unless you were aware that you could double turn no  and still be less R than star coil, you could use wire thinner wire and still do ok, and then you could wind up the other coils the same, and still remain ok, maybe that wasn't thought of, I dont know, but whatever the reasons, it IS worth exploring the possibilities further.


It would be useful for you to get accurate wind readings for your test figures. At the moment they appear quite unbelievable, mostly because youv'e blown the possible power extraction from a certain wind speed to bits. I think you'll agree that that puts them in the rubbery figures department. It is necessary that proper figures are found, so that accurate comparison of other like sized machines can be compared.


The car alternator business was unable to set a normalised frame of reference to compare one system to another. It wasn't dynamic, and would in no way give us a picture of how both systems may perform up the tower in the wind. Here blade stall and gennie matching become critical to AH in the batteries over time. If we didn't have to match these characteristics, we could wind as many turns as possible or put 24v system on 12v batteries, and let the losses fall where they may, burn out a stator or two.... probably not, blade stall may prevent this and it may never get up to speed where the airfoils generate their power effectively.


 Thats why I feel these tests will prove inconclusive. Only by comparing this machine to like machines, can we get close. After that blade design etc etc, tower height blah blah blah. Or have another stator made star to test against. But that should only be as a last resort. If we can get an  accepted power curve from it it would help the argument considerably. I'd be interested in what Danb felt may help to definatively prove the case one way or the other.


I am not qualified to compare , as I have not spent the night with only a candle because I had no power that day.


I'm not that quick to discount the air 403 design either. It looks like it may suit a jerryrig makeover. The fact that you can fine tune different parts of the power curve is nice also.


So keep the chin up, we all (well most of us anyway) have learn't something along the way, I think you'll find that you have most peoples admiration for not giving up in the face of adversity, and you have definatly not become a contender for the corner.....that position could be looming up to be mine yet..........oztules

« Last Edit: February 19, 2006, 12:07:36 AM by oztules »
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Flux

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Re: Test alt stator #1 of 3.
« Reply #10 on: February 19, 2006, 02:38:56 AM »
Oz

Just a comment not relevant to Jerrys discussion.

There is no issue with delta for motors running on a sinewave supply. Delta is used for convenience in large machines, the wire size is easier to manage and it allows the star/ delta start option.


The issue only concerns rectifiers and similar non linear loads. When harmonics are present they circulate within a delta winding. This doesn't mean we shouldn't use delta if it gives us other advantages such as a better match to the prop. Star /delta change is fine. When we use one winding for all conditions then why not use star and get a bit more in low winds.


The electrical industry in general doesn't face some of the issues that bother us so some of the conclusions may not be the same.

Flux

« Last Edit: February 19, 2006, 02:38:56 AM by Flux »

oztules

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Re: Test alt stator #1 of 3.
« Reply #11 on: February 19, 2006, 03:37:55 AM »
Thanks for the clarification Flux.


You are indeed a mine of information. Your insights into the intricicies that most of us overlook are particularly useful. I knew the diodes were nonlinear devices particularly from AM demodulation theory decades ago, and in pwm systems that I have built (and struggled with) but i never stopped to think of it in regards to ac dc rectification in low frequency systems.


Never to old to learn new stuff ..even about that which you had taken for granted that you knew, when actually you hadn't followed some now obvious implications that may go with it.(obvious when someone points it out, didn't seem to stumble on it for decades before now)


Tell me, where is the actual difference between the efficiency of the two wiring styles. Why is it that star being more efficient is an almost motherhood argument or is it only in this application.


I have tried to get a grip on why this might be the case, and i just can't pick it.

(although i didn't pick the 3:1 resistance between the two systems either...so much to learn......


as always.....dazed and confused.........oztules

« Last Edit: February 19, 2006, 03:37:55 AM by oztules »
Flinders Island Australia

Flux

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Re: Test alt stator #1 of 3.
« Reply #12 on: February 19, 2006, 04:25:00 AM »
For normal sinewave operation there is nothing between star and delta. The root three difference in voltage is cancelled by the root 3 squared (3 times change in equivalent resistance)


In star the voltages add vectorially from phase to line. In delta you add the currents vectorially.


Neglecting any circulating current due to harmonics there is nothing in it, for a motor on a normal line use either.


For alternators star is generally preferred but mostly it is a convenience thing with the ability to ground the neutral. With rectifiers star is universally used. Car alternators, exciters for synchronus machines and anything else using a rectifier load are all star connected.


If we are doing a motor conversion and want to use the existing winding then it may be an advantage to use delta to obtain the best ratio. If starting from scratch with a new winding it would make more sense to use star.


There are times when it is better to have a delta winding to circulate the harmonics rather than having a floating neutral but I won't throw any more confusion in at the moment.


The extra loss from delta in rectifier circuits can be up to 10% with the size and type of winding used here and it happens at the instant the diodes conduct ( low wind).

Flux

« Last Edit: February 19, 2006, 04:25:00 AM by Flux »

zap

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Re: Test alt stator #1 of 3.
« Reply #13 on: February 19, 2006, 08:41:02 AM »
Jerry I apologize, like I said I wasn't criticizing by any means and I apologize for taking attention away from you ongoing experiments. Your workmanship always comes across as very professional and make mine look like child's play. Most of my projects would be deemed unacceptable for the Red Green show.


Solvent welding basically dissolves a little of each piece being joined, the polymer chains mix together, the solvent evaporates and the polymer chains stay mixed together.  If you've every glued PVC pipe together then you've done solvent welding.  For plexiglass, styrene and ABS something like Ambroid PROWELD http://www.ambroid.com/Ambroid.html#110 will produce a bond just slightly slower than superglue.  I think I got my last bottle for $3 and unless you leave the cap off, it lasts and goes a long way.  A plus is the ability to fix many plastic items and sometimes have the repair barely visible.


Hobby and Craft stores usually carry some type of plastic welder also many sign shops carry similar products although the sign shops I've approached usually charge an arm and leg for the stuff.


Once again, my apologies and now I go to the corner and don the dunce cap.

« Last Edit: February 19, 2006, 08:41:02 AM by zap »

finnsawyer

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Re: Test alt stator #1 of 3.
« Reply #14 on: February 19, 2006, 09:22:21 AM »
The Jerry rigged configuration is delta, but not delta and circulating harmonics need not apply as long as the windings are not connected together.  The rectifiers apply isolation.  This means that slight imbalances in the windings can be more easily tolerated.  And I think that would be the advantage of Jerry rigging over a true delta configuration.  Or have I missed something?
« Last Edit: February 19, 2006, 09:22:21 AM by finnsawyer »

elvin1949

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Re: Test alt stator #1 of 3.
« Reply #15 on: February 19, 2006, 10:19:13 AM »
Jerry

 I tend to think you could very well be right.

Time and lots of testing will tell.

 I am working on a small vawt think i will

wire it your way. Can't hurt

later

elvin
« Last Edit: February 19, 2006, 10:19:13 AM by elvin1949 »

Flux

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Re: Test alt stator #1 of 3.
« Reply #16 on: February 19, 2006, 10:40:23 AM »
Yes Jerry's method does block circulating currents from unequal voltages and promises an improvement in that respect.


The third harmonic circulation is not blocked and it shows when the rectifiers conduct but the effect seems to be reduced. I have found Jerry to be a bit better than delta on the two tests that I have done.

Flux

« Last Edit: February 19, 2006, 10:40:23 AM by Flux »

Jerry

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Re: Test alt stator #1 of 3.
« Reply #17 on: February 19, 2006, 05:57:30 PM »
Hi Flux.


I wound the second stator today. Its the 21 ga. twice the circular mills of the 24 gage.


I was able to get the 116 turns you've sugjected out of the 21 gage. You sugjested 21.5 gage and since thats hard to find I thought I'd try to get the 116 turns with the 21 gage and it was tight but the stator is cast and all look well.


I think using the 21 ga. rather than the 21.5 will be a benifite to the star stator.


Help its amperage out a bit.


I may still wind the 100 turn 21 gage stator. 100 turns should be the exact amount copper as 200 turns of 24 ga. So those 2 stators would have the same amount of copper.


116 turns of 21 gage I think will have a slight edge ( handycap, cruch, head start , cheat) or what ever you want to call it.


Just another thought here. there has been some discusion here about the isues of blade and requiered touqure and such.


At this point I'm not concerned with the blade only the alt.


My disire is to achive the highest power output of the magnets, copper and space I have available.


After the alt is maximized and power data harvested then the blade will be designed to acomidate such an alternator.


I know wind speed is also part of the equasion but so is an alt that doesn't  waist magnetic flux and copper and coils not delivering all the power there capable of.


                           JK TAS Jerry


                             

« Last Edit: February 19, 2006, 05:57:30 PM by Jerry »

Jerry

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Re: Test alt stator #1 of 3.
« Reply #18 on: February 19, 2006, 10:06:58 PM »
Hi Zapmk.


Your right about the stone age. It was just a couple years ago that the disc rotor alt was the machine to build. I remember a few years discusions about laminations. At that time single rotor alts with laminations was the DIY state of the are.


So things do change and better ideas are developed and become standard. Its the ongoing persuite of best preformance.


Heres a couple pix of the the shaft, bearing support, magnets discs (old speaker magnet backing plated). One is of the stator resting on the magnets discs.


I'll try to glue the magnets to the discs tommorow?


   








                     JK TAS Jerry

« Last Edit: February 19, 2006, 10:06:58 PM by Jerry »