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401
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by brandnewb on February 22, 2024, 08:14:19 AM »
So gang. first most please accept my humble apologies for being stubborn.

It is one of those self defense mechanisms that kick in when information gets too difficult for me to process in a, for me, suitable time frame so I just default back to where I was.

It is nothing personal nor will it ever be.

So here is my update thus far.

!!If at any time someone feels I should demonstrate because something does not make sense then please do so to signal that. Because then I will and maybe we find I blundered again.
If it all makes sense to you then I am also content to just go with this flow!!

Context: 300mm radius ID of magnets spaced at a 3.75 degree interval.
Considering non stacked (traditionally spaced with an air gap of around 20mm (4 times that of the magnet thickness) 24 coils per phase) coils even though wider of nature than stacked coils will need about 280 winds to end up in the 2.something volts sphere.
While when stacking coils (48 per phase) in this context only needs coils to be 50 winds to end up in the 1.something sphere of volts.

And I think I can explain why.
You see magnetic fields when induced by electromagnets (the coils) they do interfere with each other. But then in a good way. In where overlapping phases compound.
And here comes the kicker!! The adjacent pole in the same phase does not counteract the other. Not al all!

I just love magnetic fields soo much ;) If only I understood them ;)

Overmore the field around said coils is non biased for direction. It is a sphere so that means that my earlier worry of having tilted coils would harm the interaction with the magnets seems debunked.
But I know for sure once I start the torque tests. Now I am still in the finding out what configuration actually stands a chance of getting where I need to get.

Anyway all this has set me back on track with the original plan to go for a large diameter. a 300mm ID {1}inner radius{/1}was just to see. Now I have seen and I can tell. Nah that diameter will never work for my goals of having 52vAC at 3.7Hz (yes it is 3.7Hz not 3.8Hz like I have been mentioning earlier)

Also Ed, You know that I love you so that is why I have not send back the 16 magnets yet. I will keep them ready and waiting so that later on once I have some real life data I can setup a gear ratio to have this suggested setup spin around 20 times faster than what I am making. Just to compare results.
In case my configuration lacks behind then we have a clear indication why not to go with a direct drive for a low RPM VAWT.

I have more to say but no time to write it now.


402
Newbies / Re: electronics learning kits
« Last post by JW on February 22, 2024, 03:15:33 AM »
Forest Mims  "mini notebooks"
 https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2540003.m570.l1313&_nkw=forest+Mims+mini+notebooks&_sacat=0



https://www.ebay.com/itm/254495705263?itmmeta=01HQ7Y65PC89JS7MP9PKA5NHNV
403
Newbies / Re: electronics learning kits
« Last post by JW on February 22, 2024, 02:47:48 AM »
 




 https://www.ebay.com/itm/404797311302?itmmeta=01HQ7WA3DF5FSZJDCFPSC4S1HV
 

HAAA!
I knew I could find the kit with the bread board  :)
404
Newbies / Re: electronics learning kits
« Last post by JW on February 22, 2024, 02:28:39 AM »
https://www.ebay.com/itm/134940591650

405
Newbies / electronics learning kits
« Last post by JW on February 22, 2024, 01:46:37 AM »

 https://www.google.com/search?q=electronic+learning+kits+200+and+wiz-serp
 https://www.ebay.com/itm/116017994233?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0

https://i.ebayimg.com/images/g/9VgAAOSwOnRlhhgO/s-l1600.jpg



https://www.ebay.com/itm/116017994233?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0
406
Storage / Re: Sand Batteries
« Last post by Mary B on February 21, 2024, 07:54:01 PM »
Saturate the sand with a liquid that works well to transfer heat... if it is a closed system you could even use waste oil from changing it on the car/truck/SUV...
407
Storage / Re: Sand Batteries
« Last post by Bruce S on February 21, 2024, 11:47:42 AM »
machinemaker;
The little "test" units I built convinced me that going the route of tube-in-tube . Might be called heat exchangers.
My old Mercedes had two copper tubes, one inside the other, I plumbed the outside pipe through my coolant system that in-turn warmed up the bio-diesel.
The guy who bought the car was schooled on how it all worked and why I had two separate fuel tanks.
 I'll dig around and see if I still have a pic of the setup.

I found that heating the sand is actually quite easy, but getting the sand to give up the heat was much harder.
So I'm going to rebuild it and use the tube-in-tube heat exchange setup to see if it's a bit better.
I'm thinking of building a heliostat to use the sun directly to heat the sand area rather than rely on diversion dump loads to connected to a NiChr bank heater.

Cheers
Bruce S
408
Storage / Re: Sand Batteries
« Last post by machinemaker on February 21, 2024, 10:55:10 AM »
Back in the 60s or 70s I used to see articles and ads for plans for sand heat storage. This was before outdoor wood furnaces became as popular. The idea was that you had a wood-fired stove in a small building, the exhaust from the stove went through a system of stove pipe above the stove. All of this was enclosed in a well-insulated small building. The space around the stove and the walls of the building was filled with sand. In the sand, tubing was laid out to heat water or ductwork to heat air. The idea was that the wood stove would burn hot and fast, and the heat transferred to the sand for storage.  I have considered doing something similar to heat a greenhouse, but surround the wood stove with old and patched water heater tanks, plumbed in series or two series. Then fill this well-insulated building,( 2 x 6 walls with 2” bead board on the interior) filled with sand. I figure I can get 8 forty gallon tanks around the wood stove. All the tanks would be non-pressurized and vented.
409
Storage / Re: Sand Batteries
« Last post by Bruce S on February 21, 2024, 09:45:48 AM »
Yes I have  ;D.
I used an old toaster NiChr to build one using a couple tins and cheap play sand.
Worked pretty well to heat the sand, but getting the heat back out of the sand is a lot harder than even I expected.
I'm currently working on redoing it by using a tube-in-tube setup like I did for my bio-diesel heating system.
Below is a link of the vid that I used to model mine from.

https://www.youtube.com/watch?v=Icai6OOIh2M

Hope this helps
Bruce S
410
Wind / Re: axial generator with lamination core
« Last post by mbouwer on February 21, 2024, 08:06:21 AM »


9 coils / 12 magnets.
According to the Bavaria Winding Diagram Table, 9 coils / 10 magnets would be a better combination.

Attachments: mini axiaal ..JPG * mini axiaal ..JPG

411
Wind / Re: Classical US multibladed metal wind rotor....?
« Last post by MattM on February 21, 2024, 06:46:27 AM »
Primitive central American versions

412
Wind / Re: Classical US multibladed metal wind rotor....?
« Last post by topspeed on February 21, 2024, 03:23:11 AM »
Quote from: mbouwer on February 13, 2024, 06:32:10 AM
(Attachment Link)

In the eighties I made a multi bladed mill with a downward drive and there a transmission drove a dynamo.

Awesome where is this ?
413
Wind / Re: Classical US multibladed metal wind rotor....?
« Last post by topspeed on February 21, 2024, 03:21:53 AM »
One displayed on this music video.



414
Storage / Re: Sand Batteries
« Last post by DamonHD on February 21, 2024, 03:16:32 AM »
Heard of them.  I have a small non-sand heat battery at home.

Rgds

Damon
415
Storage / Sand Batteries
« Last post by SparWeb on February 20, 2024, 11:29:37 PM »
Anybody heard of them?  Tried to build one?

I just heard about this, and saw a video about building one.  This "battery" is meant to store heat, not electricity.  There are a few examples in commercial use or experiments, and I found a DIY video on Youtube.
416
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by JW on February 20, 2024, 02:06:19 PM »
Here check this out don't be afraid of the link...

   Maxitronix 200 in 1 Electronic Project Lab - Educational Fun Basic Electronics


https://www.ebay.com/itm/325986261679?chn=ps&_trkparms=ispr%3D1&amdata=enc%3A1w69pfJeBT_G2HVVkGUhmcw63&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=325986261679&targetid=1585159290171&device=c&mktype=pla&googleloc=9013362&poi=&campaignid=19894961968&mkgroupid=148855406073&rlsatarget=aud-1317302328205:pla-1585159290171&abcId=9307911&merchantid=603800276&gad_source=1&gclid=EAIaIQobChMIg6Obms26hAMVUBmtBh0skwz4EAQYBCABEgJ0A_D_BwE

Before there was Forest Mims

The projects will at least teach you how to read a schematic diagrams
417
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by brandnewb on February 20, 2024, 03:48:15 AM »
So preliminary results show that a repelling {1}double density single rotor, dual stator{/1} setup is indeed a dead end and quite frankly a bit of a foolhardy idea to begin with ;).
I can only get a few winds in a coil at best before the coil gets so tall (2 maybe 3 layers only) the field already drops to unusable values.
So finally I can close the books on that concept.

Now it is still the question "to stack coils or not to stack coils".
But I am leaning against it because although I have not yet demonstrated it I am not sure what the magnetic field in the coils will do when they are tilted diagonally slightly. I can only imagine it will not benefit the interaction between that field and the magnets.

Another, perhaps far more important reason not to stack coils. One that I have demonstrated already is that with having coils stack then heat dissipation rates drop to near zero. Ok truth be told I have not really sunk my teeth into that problem yet to see if I can fix that.

Anyway. I can generate around 1.17vAC at around 3.8Hz with a single stacked coil pair when each coil in that pair has 50 winds (I am ignoring coil{2}wire{/2} size for now).
And theoretically we can have 48 of those stacked pairs per phase making for around 56vAC at 3.8Hz. In practise I will need some empty coil slots at every stator segment else not be able to (de)install it in a modular fashion.

For traditionally spaced coils we can have 24 coils per phase. But the good thing about the coil shape in this scenario is that it can be wider. Maybe even enough more wide to compensate for the extra winds needed to be able to reach around 2.1vAC per coil at 3.8Hz.
And then of course all the added benefit mentioned earlier.

reporting back once I managed to figure out how much winds that is.

418
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by MagnetJuice on February 20, 2024, 02:03:59 AM »
QUOTE from MagnetJuice:
After your many requests for help, I'll agree to help you with the design of the alternator for your Phoenix VAWT.

QUOTE from brandnewb:
Thank you Ed,
This means the world to me!

QUOTE from MagnetJuice:
I don't know how successful I will be in getting you back on the road, but I am going to give it a shot.

I failed.  :(

QUOTE from brandnewb:
Now what I am looking for is either to hear "sounds like a plan" or "nah this is a bogus plan and I will tell you why"

I told you why but somehow you missed it.

QUOTE from brandnewb:
I will report back once I have reached my goal.

I have no idea what your goal is but carry on, and the best of luck.

Ed
419
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by brandnewb on February 19, 2024, 10:17:39 PM »
the topic seemed to be headed into the right direction with early contributions of Joestru and MaryB but then got really confusing with images of alternators that clearly will not help both getting an answer to this topic and second to my overall goal of reaching a high voltage at low RPM.

And then to think all I wanted was to stay focussed on a clear goal.

I even reminded about that here in this thread.

I will report back once I have reached my goal.

Quote from: brandnewb on February 08, 2024, 01:42:10 PM
Thx guys for the input.

Yet I feel we are diverting from the matter at hand.

Please focus solely and only on the matter at hand as outlined below;
 
1) create a bunch of different test coils varying from 0.4mm diam wire size to 1mm diam. and also in shape.

Do make sure that the 0.4mm wire coils are at all times 4 x more winds than the 1mm one. As one can fit only 4 times that wire in the same space of a 1mm one.

2) run various magnet configurations over all variations of the coils at the intended frequency. for single density that would be around 3.8 Hz and for double density that would be double that.

3) record what voltage each coil can produce at said frequencies,

4) hook up an Variable Frequency Drive to the variac at the intended frequency and at the voltage level it would have produced while induced by the magnets spinning.

5) now measure the magnetic field on each coil making sure to also take into account the depth and area it encompasses ( larger is better for breaking ability)


Now what I am looking for is either to hear "sounds like a plan" or "nah this is a bogus plan and I will tell you why"
420
Temporary power / Re: When the power goes out
« Last post by JW on February 19, 2024, 07:56:56 PM »

 I feel the same about these battery bank systems. These battery systems are just too new. Also I don't like the 600v to 800v running volt systems. there's been concerns from first responders with auto accidents. I've seen fire trucks hose down the batt banks and after 10 hours they still cant put them out.

I preferer a low voltage systems(100v max DC) myself. We all know there is a need for better battery systems. During with my work with my invention of a "4 cycle steam engine" I also patented (for education) a variable lift direct injection valve. In order to make  it lift it needed water cool the electromagnetic coil conductor. We can do better with high amp low volt systems.

I actually patented the thing   https://patents.google.com/patent/US8261575B1/en
It uses centrifugal force at running speeds to self pump the coolant thru the armature coil wires. 

its a low voltage traction motor design for an EV. Why cant we have EV that will burnout and smoke the tires like a hotrod.

There should different types of EV's       
421
Temporary power / Re: When the power goes out
« Last post by ChrisOlson on February 19, 2024, 10:18:40 AM »
Quote from: XeonPony on February 19, 2024, 09:51:28 AM
Tesla used the worst possible battery chem to claim the range, Compare to the Nissan leaf has never had a battery fire, but they can't boast the range, just bullet proof reliability, sadly most them are copying Teslas sh*t battery system, so we'll be seeing more fires.

the more energy dense the battery is the more fragile it is to keep it from spontaneous release of said energy.

For our daughter it was a rather expensive lesson. These things are piling up on car lots and they can't sell them. I think I read where one of the major car rental outfits is dumping their EV fleet and going back to gas engines because the EV's are too expensive to operate and maintain. Which is going to further depress the used market for them. Like all fads, they hit their peak and then reality sets in.
422
Temporary power / Re: When the power goes out
« Last post by XeonPony on February 19, 2024, 09:51:28 AM »
Quote from: ChrisOlson on August 04, 2022, 10:27:15 PM
We had a Tesla that caught on fire here on County V over the weekend. It reportedly quit going down the road. The two people in it got out and noticed smoke coming out of it. They got away from it before it exploded. It caught on fire just after lunch last Saturday. The fire dept worked on putting it out, but it was still burning on Sunday morning. It got so hot it melted the road and set that on fire, set the ditch on fire, thankfully it was by a swamp so they kept the fire from spreading. But they used 13,000 gallons of water just to keep it cool enough so the asphalt in the road wouldn't keep burning.

It is now like a superfund cleanup site. The amount of water required to control it resulted in groundwater contamination right by a swamp. A few thousand yards of dirt, and a section of the road have to be dug out and hauled to a toxic landfill someplace, and then replaced and the site restored. They've been testing the material removed and it was more extensive than originally thought. There's toxic materials still coming out of the site and they've hauled 30-some dump truck loads out so far. Out here in the country they didn't have the convenience of a storm drain system like they have in cities that could capture the toxic runoff.

Plus not sure who's going to pay for it. Lithium batteries are hazardous materials and are subject to DOT's Hazardous Materials Regulations (HMR; 49 CFR Parts 171–180). It's illegal to even ship one under 49 CFR section 173.185 without all the proper hazmat insurance and paperwork. And then they put them in electric cars? They're going to have to include an environmental hazardous materials surcharge on EV insurance because when one catches on fire they are an environmental disaster, and they are extremely dangerous. This is well known, but little is done about it because they are the latest political posturing statement that politicians can use to claim they're gonna "save the planet".


Daughter has had zero luck getting rid of her Tesla. We bought her a nice Jeep Compass and she's stopped making the payments on the Tesla. She's gonna let the bank take it. Not really all that great for her credit rating, but at this point she has no choice. Elon Musk is a fraud anyway that has sucked millions of people into his scams that he funds with taxpayer dollars thru government subsidies, including Tesla. If you're interested, there's a pretty good series that presents the facts.

https://youtu.be/c-FGwDDc-s8

https://youtu.be/DopFo1rjAr4

Tesla used the worst possible battery chem to claim the range, Compare to the Nissan leaf has never had a battery fire, but they can't boast the range, just bullet proof reliability, sadly most them are copying Teslas sh*t battery system, so we'll be seeing more fires.

the more energy dense the battery is the more fragile it is to keep it from spontaneous release of said energy.
423
User Diaries / Re: Score of a life time!
« Last post by XeonPony on February 19, 2024, 09:40:13 AM »
6 total this season, sadly the 7th required some lead supplement, but the fox will have a very healthy litter of pups so natures balance is held.

15868-0

Attachments: Screenshot_20240201-124558.png * Screenshot_20240201-124558.png

424
Fabrication / Re: What do you use for welding
« Last post by XeonPony on February 19, 2024, 09:39:41 AM »
Finally got my self my dream:

15862-0

15863-1

15864-2

15865-3

15866-4

15867-5

Plasma cutter works amazing what a difference to using gas or disk, and the tig welding / stick works great.

Attachments: IMG_20220328_190110.jpg * IMG_20220328_190110.jpg IMG_20220412_172946_2.jpg * IMG_20220412_172946_2.jpg IMG_20220423_055021_2.jpg * IMG_20220423_055021_2.jpg IMG_20220317_195050.jpg * IMG_20220317_195050.jpg IMG_20220911_175610.jpg * IMG_20220911_175610.jpg IMG_20220703_123855.jpg * IMG_20220703_123855.jpg

425
Logged in diaries / Re: VAWT backyard experiements
« Last post by MattM on February 19, 2024, 07:00:27 AM »
Quote from: Mary B on February 18, 2024, 09:58:28 PM
Quote from: MattM on February 18, 2024, 05:33:21 PM
This guy went with an exterior scoop, and its a pretty similar radius IMO.

https://www.youtube.com/watch?v=h-FqF21wyLc

Notice his pulley size.

That is a lift/drag type wing, a different design philosophy...
Its a modified Lenz, so its a different scoop design.  The point of the link is to show how massive the pulley ratio he went with.  I personally would have gone two smaller stages using chains, but that is just my preference.  It was going to be loud regardless of the choice.
426
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by Mary B on February 19, 2024, 03:33:34 AM »
Quote from: MagnetJuice on February 19, 2024, 01:44:44 AM
Yea guys, I agree that he should learn at least some basic electricity.

However, I recalled that he said a couple of times before that he has some difficulties learning from reading text.
There is still a lot that can be learned by watching videos and by personal experience.

That is one of the reasons that I recommended to him to build a small alternator.

brandnewb,

If you get the magnets and the steel plates that you ordered, hold on before you start assembling things. It has to be done in a certain order and a certain way.

Ed

That is where the Forest Mims books come in handy, they do small hands on experiments to how the principals being taught... basic equipment needed, multimeter, a breadboard is handy(if it wasn't so dang expensive I could mail him one!), along with a few basic electronic parts that are easy to source, RS Electronics in EU, Digikey has EU offices, Allied has EU offices...

Ohms law is really easy to understand once yu do it hands on! And it is the most used math when dealing with designing a wind turbine.
427
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by MagnetJuice on February 19, 2024, 01:44:44 AM »
Yea guys, I agree that he should learn at least some basic electricity.

However, I recalled that he said a couple of times before that he has some difficulties learning from reading text.
There is still a lot that can be learned by watching videos and by personal experience.

That is one of the reasons that I recommended to him to build a small alternator.

brandnewb,

If you get the magnets and the steel plates that you ordered, hold on before you start assembling things. It has to be done in a certain order and a certain way.

Ed
428
User Diaries / Re: Score of a life time!
« Last post by SparWeb on February 19, 2024, 01:24:27 AM »
Xeon has a little lamb, little lamb...
Adorable.
429
Logged in diaries / Re: VAWT backyard experiements
« Last post by Mary B on February 18, 2024, 09:58:28 PM »
Quote from: MattM on February 18, 2024, 05:33:21 PM
This guy went with an exterior scoop, and its a pretty similar radius IMO.

https://www.youtube.com/watch?v=h-FqF21wyLc

Notice his pulley size.

That is a lift/drag type wing, a different design philosophy...
430
Solar / Re: 48VDC LiFePO4 pack with TS45 and Victron 385W 48VDC inverter
« Last post by bigrockcandymountain on February 18, 2024, 09:23:48 PM »
If the batteries are charged, and no loads taking power, it would be normal to have 110v on the solar pv input side.  It just means the charge controller isn't letting current flow through, so the pv modules output their open circuit voltage (voc) 

Your low voltage disconnect suggests that the batteries aren't full.  Maybe your charge controller is staying in Float, and the rebulk voltage is too high?
Are you using custom voltages or preprogrammed ones? Does the tristar have a setting for lithium? I have one in the basement running, but I don't remember anything about lithium settings. I have lead. 

Also, what is your low voltage disconnect set at?
431
Solar / 48VDC LiFePO4 pack with TS45 and Victron 385W 48VDC inverter
« Last post by jwgorman on February 18, 2024, 08:56:06 PM »
I have a 900W of PV connected to a Morningstar TS45 (PWM) charge controller connected to a 48VDC pack made up of (4) 12V LiFePO4 batteries in series. Also have a 48VDC 375W Victron inverter attached to this battery bank for AC loads. It was working fine, but possibly it is a set of very sunny days but the Low Voltage Disconnect (LVD) feature which is enabled now seems to keep triggering a lot. does anyone have advice on the TS45 settings to avoid this? It looks like on a good day, the solar PV voltage comes down to the battery voltage but in my case it is up around 110VDC. Thanks, John

Attachments: ts45_chargingCurrent.jpg * ts45_chargingCurrent.jpg

432
Logged in diaries / Re: VAWT backyard experiements
« Last post by MattM on February 18, 2024, 05:33:21 PM »
This guy went with an exterior scoop, and its a pretty similar radius IMO.

https://www.youtube.com/watch?v=h-FqF21wyLc

Notice his pulley size.
433
Wind / Re: Appropriate generator characteristics for small wind turbine
« Last post by JW on February 18, 2024, 04:47:23 PM »
 
   
434
Wind / Re: Appropriate generator characteristics for small wind turbine
« Last post by kitestrings on February 18, 2024, 04:34:59 PM »
Hi Lars, and welcome.

You have a really sleek looking turbine; some nicely printed pieces for sure.  I hope to see more as things develop.  You've probably already figured out that you'll get a wide range of perspectives here on any given topic, and the trick is to wade through them.  In the end though, I believe it helps the design process.  The comments have been good.  I don't have a lot to offer, but for what it is worth...

I think your blade connection at the hub may be something you have to beef up.  I'd be concerned that the reduced width might be a weak point without added thickness or some sort of strut.

A couple of us here have been using MPPT type controllers (Midnite Solar, Classic).  They are not a true "feedback and adjust" as with solar, but rather they allow you to input a power curve that follows the curve of the alternator.  One benefit though, is that the curve can be tweaked, if it is not perfect from the start.

I do agree that it is best to attempt to keep things electrically loaded to the extent possible - I think that was Sparweb's intended message.  Side-furling works well.  It's time proven.  If a turbine runs unloaded, in a good wind site for any amount of time though I would say it is only a matter of time before something fails.  It will spin up to rpms that it is not equipped to handle, furl, slow and repeat.  To touch here on that "wide range of perspectives" I mentioned earlier, here's a prime example where we get deep in the theoretical discussion on the one hand, but then make broad-brushed summations based on very limited, antidotal experiences on the other.

Good luck, and I hope to see more, ~ks
435
User Diaries / Re: Score of a life time!
« Last post by XeonPony on February 18, 2024, 10:32:38 AM »
Quote from: Mary B on February 18, 2024, 10:28:02 AM
Looks like you are going to have a god shearing this spring!

It is all ways entertaining, my hands ache thinking of it.
436
User Diaries / Re: Need more batteries
« Last post by XeonPony on February 18, 2024, 10:30:05 AM »
you'll learn you never have enough batteries lol!

for years I lived off of 10.3kwH of lead acid (5.5kwH usable) just too small

Now got 18.4KwH of lithium (12.9KwH usable that's to 80% depth of discharge, safe for lithium's) got to add 2 more sets yet!

But I can tell you, do what ever you need to get to 48v as that will be the largest pay off long run for ya!

The Hybrid inverters deff pay off too, some people have done nifty things with the settings to make them really perform as a solar first utility second device.
437
User Diaries / Re: Score of a life time!
« Last post by Mary B on February 18, 2024, 10:28:02 AM »
Looks like you are going to have a god shearing this spring!
438
User Diaries / Re: Score of a life time!
« Last post by XeonPony on February 18, 2024, 10:21:23 AM »
Baaaaa!

15856-0



15858-2

Attachments: IMG_20231226_133939.jpg * IMG_20231226_133939.jpg cropped.jpg * cropped.jpg IMG_20231226_133945.jpg * IMG_20231226_133945.jpg

439
User Diaries / Re: Score of a life time!
« Last post by XeonPony on February 18, 2024, 10:18:10 AM »
Well 1 year to date and the one battery set has done great. Traded the old lead acid bank and its accessories for the winters sheep feed, feel naked with out it, so guess time to get the last ones online and make a fire proof enclosure for them!

Still have a lot of the spare parts, if any interested! Second set was no steal like the first heavy swelling in some, so just use them till they pop and save, save, and save some more to buy some lithium iron phosphates for when they go.

15852-0

15853-1

15854-2

15855-3

As they say, can't win them all, they did recover to full rated voltage.

Attachments: IMG_20230820_111445.jpg * IMG_20230820_111445.jpg IMG_20230820_111525.jpg * IMG_20230820_111525.jpg IMG_20230820_115259.jpg * IMG_20230820_115259.jpg IMG_20230820_115349.jpg * IMG_20230820_115349.jpg

440
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by JW on February 18, 2024, 09:55:24 AM »
 go on ebay and find this book.  Getting started in electronics  by Forrest Mims

MAKE SURE YOU GET THE GREEN BOOK
441
How to work with images / Re: How to attach pictures
« Last post by JW on February 18, 2024, 09:48:36 AM »
here's what I found

https://www.fieldlines.com/index.php?action=kitsitemap&board=5.50
If you look at the list on left side and click one, you will see that topic is totally intact.

There is one of every category we need to make a copy on CD this may hold up to 50 or we could use something else to store this on. While things are good we need to do this.
442
Wind / Re: Appropriate generator characteristics for small wind turbine
« Last post by Adriaan Kragten on February 18, 2024, 03:44:16 AM »
Quote from: SparWeb on February 16, 2024, 11:15:31 PM
Hello Lars,
Have you set up with wind turbine outdoors in the wind yet?

NEVER RUN A WIND TURBINE UNLOADED.

If it isn't allowed to run a certain wind turbine unloaded, there is something seriously wrong with the safety system. The safety system which limits the rotational speed and the thrust must be that good that even an unloaded rotor won't be destroyed at high wind speeds. Reduction of the rotational speed only by the load is dangerous because the required electronics to steer the load may fail and this results in an unloaded rotor.

I have tested the hinged side vane safety system of my VIRYA-4.2 wind turbine with an unloaded rotor and although an unloaded rotor is rather noisy, the rotor running at the maximum rotational speed gave no problems at very high wind speeds. The VIRYA-4.2 has a 2-bladed rotor with a diameter of 4.2 m with constant chord blades made out of massive mahogany wood. The design tip speed ratio is 8 and the unloaded tip speed ratio is about 12.8. The blade chord was 200 mm and the Gö 623 airfoil was used. The maximum unloaded rotational speed was about 480 rpm, so 8 rev/s. The maximum loaded rotational speed was about 300 rpm so 5 rev/s. The slender blades of this wind turbine are sensible for flutter at very high tip speeds but flutter didn't occur for an unloaded rotor.
443
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by Mary B on February 17, 2024, 10:06:19 PM »
There is a difference between mechanical resistance and electrical resistance BUT the two are tied together in a wind turbine! Electrical resistance can affect cogging... which is mechanical resistance.

Hence JW's suggestion to learn ohms law, and later maybe LC circuit calculations because adding capacitors to each phase can boost the voltage but they need to be tuned to match the frequency and reactance(think of it as ohms for a coil at a certain frequency) of the stator...

Learning basic electronics will really help you a lot!
444
How to work with images / Re: How to attach pictures
« Last post by SparWeb on February 17, 2024, 09:35:20 PM »
Are you making a backup JW?
445
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by JW on February 17, 2024, 04:39:51 PM »
Im not sure if you understand what im saying.

One thing that you have to consider, "resistance" is a dry measurement and "impedance" is what is measured on a live circuit. Again search for an engineering text and read it (book) we may have a way to referrer you a book that will cover the basics. You need to understand common nomenclature. Look into a basic solid state book so you can cover all bases.
446
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by brandnewb on February 17, 2024, 04:17:29 PM »
hahhah this newbie did find eventually a guide on how to use gravity as a torque/breaking force measuring device.

sweet.

I am going down that path!! to see if I can get anywhere with my original plan.
447
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by JW on February 17, 2024, 03:45:50 PM »
Brandnewbie,

There is something you need to take into account. ohms law https://www.fluke.com/en-us/learn/blog/electrical/what-is-ohms-law

This will be key to your calculation's.

Also it relates to your style, you can measure the coils and plug ohms law in and you will understand things differently.
448
Coil winding / Re: How to determine the lmits of a coil / magnet configuration
« Last post by brandnewb on February 17, 2024, 12:10:53 PM »
@SparWeb,
I found your 2006 document at
http://www.jimic.cl/appv/Congreso/PDF/AXIAL_FLUX_HowItWorks.pdf

It describes the Dan Bartmann Axial PMA Ed is refering to, for which I have all 16 magnets in at the moment.

But in the end you write the following
"At 80 RPM, this alternator will produce 50 Volts, unloaded. When connected to a 48V Battery
system, Dan has recorded 600 Watts at 100 RPM. (Roughly 12 Amps). This is actually a
fairly large PMA, suitable for a windmill size of about 17 feet diameter. At higher wind speeds,
the prop turns much faster and he can capture upwards of 3 kiloWatts."

This is in stark contrast to what I am aiming for. Roughly 52V open circuit at 4 RPM.

@MagnetJuice
What I meant with breaking force ability was inspired by Joestru when he mentioned mechanical resistance and MaryB when she mentioned cogging and how much force it takes to overcome it.
The current charge controller I have will short all 3 phases to slow down the turbine. But if the coil/magnet configuration can't produce enough torque/breaking force then not much breaking will happen.
On the same token, if there turbine is charging the battery bank but not much resistance in the turning is being produced then there will be very little wattage available to charge at.
449
How to work with images / Re: How to attach pictures
« Last post by JW on February 17, 2024, 11:25:01 AM »
Hey I located the master file of the complete database posts and topics for us  :)
450
How to work with images / Re: How to attach pictures
« Last post by TechAdmin on February 17, 2024, 10:50:42 AM »
If I say it's intended, clearly it's not a "problem".
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