ALTERNATIVE ENERGY FORUM - etc.
Wind => Wind Turbines => Topic started by: Caleb on May 22, 2026, 11:10:00 am
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I removed my dumb questions because I re-read the whole topic. Questions answered, sort of, the project seems to be changing so fast I really don't know what the end result will be yet.
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I'm finding things that need addressing:
I should have had larger diameter holes for the hub. It just needs a little more to go over the studs. I'm trying to decide whether to drill them out or file a little off one side.
The three long skinny magnets do not like to sit next to eachother when the poles are aligned. It will require some sort of frame to hold them together.
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The parts are done.
At least you’ve got some progress. I’m still wrapped in other projects (railway). I’ve also been promoted for want of a better word. I’m now running the Workshop. Seriously there’s not enough hours in the day!
Yeah.
I've been doing VAWTS etc. since 2007, I retired from the job in 2013. So the job was basically 15 hours per day with months away from home and I found time to do it then. WHAT ??? Now I'm retired and can't find 30 minutes.
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The parts are done.
At least you’ve got some progress. I’m still wrapped in other projects (railway). I’ve also been promoted for want of a better word. I’m now running the Workshop. Seriously there’s not enough hours in the day!
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I guess that's a good sign for the economy.
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The parts are done.
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That's awesome.
But according to Peter, "They won't understand it". 🤣
Maybe you can get them to get some wind tunnel time at maybe General Motors in Warren, MI tech center.
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No word yet on the parts. It's like he doesn't want to reply to my emails.
I was just informed that a Senior Engineering Design team might be interested in making a Sharp style VAWT to put up on Calvin's campus.
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Oh that's good, because those BERNESE can get HUGE .
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He is a Cavalier King Charles Spaniel named Buster.
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Is that a Bernese?
Name?
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Who talked you into the puppy? I was conned into Guinea Pigs which I now find myself feeding cleaning out the hutch and buying supplies for. At least I don’t have to walk then in all weathers 😂
It’s the school summer holidays here so the the women of the household are home for just over 6 weeks, so I’m busy with family stuff.
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Awesome.
I remember those needle sharp teeth.
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I've been waiting on parts, along with a new distraction:
(https://i.postimg.cc/bwFcMd1Q/Buster05.jpg) (https://postimg.cc/5XvRQ470)
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There you are!
I was starting to wonder if everybody went on vacation.
Well with ferrite magnets it will definitely spin faster under load.
I'm getting the feeling my alternator that only produces 24 watts peak will need a very large and fast turbine. Something that catches 100watts of wind just to make 24 watts. Lots of Lenzes Law working there.
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Since there will be parts for two turbines, I think I'd like to try making one with ferrites instead of Neodymium.
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Instead of subtractive fabricating maybe additive fabricating would be cheaper. Maybe a sand mold and aluminum casting the parts.
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Move the decimal to the left once and it's still too much for my budget.
At that price I would have to consider selling a kidney or something lol - that said I’ve spent quite a bit since you lot have been encouraging me. Thankfully a Tenner here and 20 quid there isn’t felt as much.
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Move the decimal to the left once and it's still too much for my budget.
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The quote came in. Enough parts for two turbines, $1560. It is a bit higher than I'd like, but not outrageous compared to online services.
I would like one for the pole, and one for mobile testing/demonstration.
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Laser cut then welded.
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Does this need to be cut out and welded or just welded?
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ChatGPT pointed me in the direction of a more local place, but Google Maps just shows a home. So maybe it is a guy working out of his garage, maybe he is no longer in business. Who knows if he will respond.
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You could call Angie's list 😁
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Certainly looks the part! Fingers crossed they don’t turn you down
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I just sent out drawings for a few parts. I hope the machine shop will take the job.
https://limewire.com/d/TvvcR#UJb96N8urj
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you've got yourself a falcon there :-)
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EEK, olive?,
Make a green outline around the setscrews.
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I can make one of them all black, because Toothless was unique. I could make one white, because the Light Fury was alone. But then what color should the last one be?
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(https://i.ibb.co/M569pHYs/Screenshot-20260627-080329.png)
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Reminds me of HOW TO TRAIN YOUR DRAGON.
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Looks fantastic!
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This is what the wing looks now, and it is close to balancing as shown. There are some weights contained in the nose. The bottom of the "beak" is even with the tip of the "tail" when it is balanced. This is close to the final design, but I have to modify the wing tips (yellow part) slightly to allow them to drain if water gets in them (printing now). I think this wing looks like a hawk ... a Hawk VAWT. Down to 313 grams. It is being held together with some masking tape for the time being.
(https://i.postimg.cc/8khY429P/Wing01.jpg) (https://postimg.cc/jCSvdFRG)
(https://i.postimg.cc/Vsjhgxpk/Wing02.jpg) (https://postimg.cc/0ryZ2B9T)
(https://i.postimg.cc/c1Qzhp2Z/Wing03.jpg) (https://postimg.cc/xq1gT49F)
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The go-kart hub arrived. Looks nice and sturdy.
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Every little helps!
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The black section is two parts. I reprinted one half with the lower percent fill and open ends. The old part's mass was 56 grams, and the new part's mass is 43 grams. It doesn't seem like a lot, but it can be felt just by holding them one in each hand. And it should mean less mass in the counterbalance. So the two halves should save 26 grams, with perhaps 20 less grams on the counterweight.
376 grams - (20 + 26 grams) = 330 grams
Or about 12% lighter.
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👍🏻✅😁
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I was wrong. The print was originally set to 10% (not 15% as stated in the previous post) so going to 5% will not be as much weight savings as hoped with the new print. However, it needs a reprint anyway because I also wanted to make the top and bottom layers open to allow any water that might accumulate to flow through to the wing. Oh well, it's a learning process.
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With enough counterweights to balance it: 376 grams.
I can go with a lower percentage fill for the black parts (5% instead of 15%). I have to reprint them anyway because some of the hole diameters need adjustment. With a little creative CAD work, the weight might be made a bit lower.
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What’s a bit heavy in grams? Just out of curiosity. It does look nice though.
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I printed one out to check it for balance and hole sizes. It is a bit heavy, but I like the looks.
(https://i.postimg.cc/bv00NP3Q/Wing01.jpg) (https://postimg.cc/Y49Lb5c9)
(https://i.postimg.cc/jj66dTZn/Wing02.jpg) (https://postimg.cc/rdmRQB6q)
(https://i.postimg.cc/KY77vbJt/Wing03.jpg) (https://postimg.cc/f3LSBG4b)
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Maybe since they resemble birds you could paint them like red wing black bird , robins, etc.
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The center shaft is a 5/8" x 5" long hex head bolt. It would extend through a hole in the base and the head would be welded on the back. The hub would rest on a washer so it doesn't drag on the base plate, and be retained on top by a nylon lock nut.
The rotor plate would have some M5 threaded holes where the arms mount. An M5 pan head screw is threaded in from the bottom and retained with some Locktite to create studs on top for the arms. The arms would be held in place with nylon lock nuts.
The plate holding the coils would just be a 16" square x 1/2" thick piece of wood, and the bobbins for the coils would be screwed to that plate with some stainless steel screws.
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The spindle and hub combination does look like a good base to work from!
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I like the GoKart hub design. The wings need some work yet. I have to tweak some things: material thicknesses, hole sizes etc.. But I think it is close to the point of sending to the machine shop.
(https://i.postimg.cc/JhLvFb4M/0615Main-Assy01.jpg) (https://postimages.org/)
(https://i.postimg.cc/s2rqLpDv/0615Main-Assy02.jpg) (https://postimages.org/)
(https://i.postimg.cc/W4vCyMbd/0615Main-Assy03.jpg) (https://postimages.org/)
(https://i.postimg.cc/tgjwchCZ/0615Main-Assy04.jpg) (https://postimages.org/)
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Just giving my unsolicited opinion ( lots of old people do this).
But given that's it's made for a very heavy load means it'll most likely have heavy duty lube, which is counterproductive to vawts. ( They need all the help they can get.) Probably rollers not balls.
Like the ball in oil in the tube with a ball, it even requires sewing machine oil to spin free.
Those bearings need to be reworked de-lubed , cleaned re-lubed and unsealed.
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Maybe I can work this into the design.
https://www.gopowersports.com/5-5-bearing-hub-110mm-pattern/
For a spindle, they just have bolts welded on to a tube. Easy peasy.
https://www.gopowersports.com/manco-dingo-spindle-2457-2458/
There seem to be lots of practical design ideas here. And they have brakes if you want to add that to a windmill design.
By the way, I found this using ChatGPT. I asked it where I could find small commercially available spindles.
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Personally, I would lean towards separate parts, I like the idea of being able to replace parts easily or having the option to change parts of the design later. After all this is well past the point of a cheap printed part that can be easily modified and reprinted.
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I'm still debating whether to make the magnet plate and hub one piece or to make the hub and bolt the magnet plate to that. Making them separate would allow them to turn the hub in a lathe and make sure the magnet plate is square with the axis. Otherwise, it would be a welded construction and there could be some wobble to the plate. Also, I could make the magnet backing plate out of thinner steel. Welding thin steel to the hub would probably warp it. I was thinking of just using the trailer spindle axle that I have on hand, but I want something that turns a little more freely.
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This is what the generator is looking like. 16 Magnets (8N, 8S) made from three 60mm x 10mm x 5mm magnets. 12 coils of approximately 100 turns of 20AWG wire. I was thinking of winding the coils around bobbins, screwing the bobbins to a back plate of wood and coating them with glass/epoxy when I think the turns are right. The yellow spacers would be 3D printed and they set the gap between the rotor and stator. The disks are 410mm in diameter. The upper one is 3/16" thick steel. The main bearings are 15mm ID flanged sealed bearings. A slotted nut would retain them. The nut and bearings would be covered by a vinyl cap to protect them from rain. I'm hoping to get 5.5 Volts rectified at 72 rpm, and deliver 2 Amps into the load through a DC/DC converter when at the rated speed of around 230 rpm. Of course that could be changed with different stators.
(https://i.postimg.cc/pr2MHdW2/Generator.png) (https://postimg.cc/TLH4jf5S)
I'm really excited to see the results of this
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I think RPM vs Current is what Midnight wind turbine MPPT controllers use. An RPM to Current graph has to be programed first and is displayed so that it can be adjusted.
I haven't priced them lately but they were very expensive but claimed twice the output of any other wind or hydro turbine MPPT at the time. That was about 10 years ago and I'm sure others have copied them by now.
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The problem I see with using a solar MPPT for wind turbines:
A solar MPPT will temporally disconnect the panel from the load and use the unloaded panel voltage to determine the energy available from the sun. This works for solar because the unloaded panel voltage responds instantly to the amount of sunlight striking it. To use the voltage of an unloaded wind turbine to determine the energy available from the wind the turbine must be running at its most efficient TSR.
It seems to me that if a wind turbine had a good TSR controller and was charging a large capacitor then there would no problem in using a good solar MPPT connected to the capacitor.
To me the TSR controller seems to be the tricky part.
I made a controller once that worked pretty well. It had a small microcontroller on it (Atmel ATTiny85) that would monitor the frequency of the generator voltage to know the rpm of the turbine. Then it would program an input current using a pwm signal. It was all open loop; just measure rpm, calculate a prescribed current, output the pwm signal and repeat. It may not have been optimal, but it did an okay job.
https://www.bitchute.com/video/Raq9J6lZnoeR
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I've got plans for an MPPT type circuit, but I want a solid generator first.
I asked ChatGPT about putting a buck/boost circuit ahead…
I wonder if the charge controller I’m using for my “instruments” project might be usable (ZK-SJ20). It has a ‘user-set’ MPPT voltage point rather than hunting for the optimal power. The module basically tries to keep the solar panel operating at that voltage while converting the power to the required battery charging voltage, so it’s not true MPPT. Obviously there’s dump load facilities but I’m not sure any of us have worried too much about that to date. Without sounding too flippant, the chance of blowing anything up seems fairly slim.
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This is the .lua file I use to generate the simulation using FEMM 4.2. I just change variable values using Notepad and open the .lua script in FEMM. I think my simulations could be more sophisticated, but that is the way I do it.
https://limewire.com/d/Lb553#EfaY4qANSz
The software is available here:
https://www.femm.info/doku/doku.php?id=start
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Some FEMM simulation results. It appears that the field strength with no backing is about 60% of that with a thick steel backing. There is very little benefit from a magnetic field point of view above 3mm for these magnets. I get the average field strength by taking a line average across the face of the magnet at 5 different distances from the magnet face (between the dots shown) and then average those results.
(https://i.postimg.cc/kgLztKBq/Fieldvs-Thickness-Graph.png) (https://postimages.org/)
(https://i.postimg.cc/s2S8PxhR/Thick-Plate.png) (https://postimg.cc/yJ1vsVjf)
(https://i.postimg.cc/cJYj7CnG/My-Plate.png) (https://postimg.cc/94mJCWbL)
(https://i.postimg.cc/tgPfdJVL/Thin-Plate.png) (https://postimg.cc/jWxZtscX)
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The problem I see with using a solar MPPT for wind turbines:
A solar MPPT will temporally disconnect the panel from the load and use the unloaded panel voltage to determine the energy available from the sun. This works for solar because the unloaded panel voltage responds instantly to the amount of sunlight striking it. To use the voltage of an unloaded wind turbine to determine the energy available from the wind the turbine must be running at its most efficient TSR.
It seems to me that if a wind turbine had a good TSR controller and was charging a large capacitor then there would no problem in using a good solar MPPT connected to the capacitor.
To me the TSR controller seems to be the tricky part.
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I've got plans for an MPPT type circuit, but I want a solid generator first.
I asked ChatGPT about putting a buck/boost circuit ahead of a solar charge controller (with MPPT) thinking the charge controller would handle the battery and the boost circuit would just get the voltage up where it could be useful. It came back with a suggestion of using a buck/boost where you have CC/CV settings and connect it directly to the battery because it confuses the MPPT circuit and it could just shut down. Seeing how I could never seem to get power past the wind turbine MPPT charge controller, that may have been happening. So this time, I'll just set the voltage to the maximum (float?) voltage for the battery, and adjust the current to match what the VAWT can handle.
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I would be very interested to see two identical,side by side vawts, one with an mppt and one without to see how much more USEABLE power is actually generated.
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"JMHO" Mine too -but- an MPPT with TSR control is needed to make it work.
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I always thought of it as : It make take more to start it spinning, but you get some of it back at the end when the wind stops with the stored inertia.
JMHO
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…they did some research into whether or not a heavy (HAWT) rotor makes a difference, and they found that a light rotor is a little better but not as much as one might think.
That makes sense in hindsight.
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I'm hoping you have better luck with yours.
If it's a success , you could market it
Combined magnet 60x30x5 ?
I'm noticing that the hard part is getting the coils to fit within the designated area. If they are too thick then the diameter of the stator and rotor needs to be increased. Not easy for me to figure out. I would probably make the stator first then make the rotor to fit the stator. (Since my math skills have much mold on them).
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Three phase. 4 coils in series per phase.
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Is that stator single phase? Lots of wire there.
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I haven't tried winding coils like this in a very long time. And now that there is magnet wire that you can solder without having to heat up the end and sand off the residue, I wanted to try them again. Besides, a serpentine of this size would require a large winding fixture. The weight may be an issue. But I did have that large stainless steel Savonius that weighed at least 40 lbs, and it was able to spin nicely. I think it will just take time to get up to speed.
My friend from Calvin University said they did some research into whether or not a heavy (HAWT) rotor makes a difference, and they found that a light rotor is a little better but not as much as one might think.
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The generator looks a bit large, but I got tired of them underperforming.
If think you’re right. This one of those ‘bigger is better’ situations. Though being bigger comes with a weight challenge.
Why have moved away from serpentine coils? Or is this the coil demonstrated on ‘wind stuff now’? I appreciate that would probably be difficult to model on CAD.
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Quid-ish ... sounds like a sport.
Don’t! You’ll start the Harry Potter fans off 😂😂😂
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I wanted a cut in wind speed of 2.5 m/s. The DC/DC converter I plan to use has a minimum input voltage of 5.5 Volts. I just estimated the rpm based on a guess of the loaded TSR. The rated current was chosen based on what I think the battery could absorb comfortably, and how much current the DC/DC converter could handle. I wanted to size the system for low wind conditions. The generator looks a bit large, but I got tired of them underperforming.
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Why did you pick that voltage at that rpm?
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This is what the generator is looking like. 16 Magnets (8N, 8S) made from three 60mm x 10mm x 5mm magnets. 12 coils of approximately 100 turns of 20AWG wire. I was thinking of winding the coils around bobbins, screwing the bobbins to a back plate of wood and coating them with glass/epoxy when I think the turns are right. The yellow spacers would be 3D printed and they set the gap between the rotor and stator. The disks are 410mm in diameter. The upper one is 3/16" thick steel. The main bearings are 15mm ID flanged sealed bearings. A slotted nut would retain them. The nut and bearings would be covered by a vinyl cap to protect them from rain. I'm hoping to get 5.5 Volts rectified at 72 rpm, and deliver 2 Amps into the load through a DC/DC converter when at the rated speed of around 230 rpm. Of course that could be changed with different stators.
(https://i.postimg.cc/pr2MHdW2/Generator.png) (https://postimg.cc/TLH4jf5S)
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😂
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Quid-ish ... sounds like a sport.
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Yeah , metric money. I like it 😁
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10 Quid 😂
That (quid) only works for money 😂😂 but about 4.5Kg (ish)
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10 Quid 😂
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Yes. At this point, I am looking at a 3/16" thick steel disk. It will probably weigh about 10 pounds (sorry, don't have the metric conversion at the moment)
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I ordered some magnets: 60mm x 10mm x 5mm. Three magnets will lay side by side for a 60 x 30 mm pole. 16 of those will go on the rotor (it will be a fairly large ~400mm diameter disk). I could get 50 magnets on Amazon for around $60.
That’s a big rotor! Is that going to be a steel disk?
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I ordered some magnets: 60mm x 10mm x 5mm. Three magnets will lay side by side for a 60 x 30 mm pole. 16 of those will go on the rotor (it will be a fairly large ~400mm diameter disk). I could get 50 magnets on Amazon for around $60.
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Manta Rays
(https://i.ibb.co/67fZnrwZ/Screenshot-20260601-103610.png)
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Looks like Sharks circling pray.
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Here it is a little more developed. A few changes: 480mm height (will have to print it in more sections), 88mm average chord (112mm root chord at the middle part of the wing), 1.2m turbine diameter
I made the center section long because I was concerned that the center of pressure for that part would be ahead of the pivot point and might make it unstable. This way, the center of pressure is in line with the pivot.
(https://i.postimg.cc/TPF0CBW6/My-VAWTRev-BWing.jpg) (https://postimg.cc/Ny8R0J4J)
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What about Mola looking wings with the wide center section have a self staring cross-section and the long skinny part have a high performance cross- section? Or just motorize the alternator for startup? It seems like an electronic control, based on input from an anemometer, could work without too much power draw.
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Have you ever considered a flexible hinge instead of a regular type?
Whatever happened to the Sharp turbine at the top of the 300 foot tower?
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Yes, it is a Sharp VAWT. I know I said I wanted to keep it simple and avoid the moving parts, and maybe they should be fixed. But then they would have to be even stubbier, with a base chord about 3x wider.
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Are those articulating blades?
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I know this looks a little goofy, but I want to give it a try. I think it will spin about 20% faster than the Savonius I had planned, and the central axis assembly will be simpler. The generator magnets would be mounted to the round steel plate, and the coils would be mounted below it (one sided generator). This is just a crude mock-up using a model from a previous VAWT with the proposed wing shape; full elliptical wings 390mm tall, 110mm root chord. The turbine is 1.3m in diameter. The average chord would give it a solidity of 0.20. On paper, the total VAWT area is a little larger than necessary. But some of the wing will be blended into the pivot, and there are losses at the wing tips, so maybe it will be an appropriate size. But I'm not sure if the regular power equation even applies when the VAWT is so flat. The coefficient of performance might drop significantly.
(https://i.postimg.cc/q7T9kDw7/My-VAWTRev-A.jpg) (https://postimg.cc/hX2CsrHF)
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That's why I try to prove a theory by using cheap junk first. I've never actually made one with permanent components because I can't find anything that satisfies my hunger for POWER. I would be extremely happy with something that approaches half the " power in the wind " formula predicts.
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One thing I struggle with is I want to design from point A to point B using a straight line with logical steps. But what ends up happening is I start reconsidering past assumptions and goals and run around in circles. Looking at the generator, it looks like I will need about $120 in magnets to get the voltage I want at the cut in speed using a wire diameter that can handle the current needed at the higher power. So, now I am wondering if it would be better to use a lift type VAWT to get higher rpms. The extra speed might get the magnet cost down to around $80. It would also be very nice to build something that looks like the Mola VAWT. It would make the bearing system simpler/smaller. So now I am vacillating on that too. Arrgh! I'm sorry. I must be ADHD or something. This sort of thing happened when I was designing machines as well. There were times I would get into a project and suddenly decide to reconfigure everything. That was usually a good thing, but annoying.
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I've been trying to work out the generator design. But family stuff is making that difficult right now. Nothing bad, just normal stuff that is taking a lot of time.
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Any progress?
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I'd like to see the results with and without all the gizmos
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I had forgotten about a hybrid (wind+solar) charge controller I bought a while ago. Documentation is sketchy, but it says something about a boost converter for wind energy and MPPT. I never installed it, and I think I'll give that a go and see if it works. It would save a lot of development work. All I have is a model number: DHS-GPI-8060
Also, ChatGPT said that one should not connect a boost converter with CC/CV output to an MPPT charge controller. It confuses the charge controller. That might explain why I could not get any output when doing that in previous tests.
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For a Bent Wing turbine with a diameter .5m or larger the Reynold's numbers should not be a problem. In testing my small .16m diameter models the TSR does not drop much until the wind is below 5 mps. Above 9 mps any TSR improvement is too small to measure. I am hoping to get some accurate Cp numbers by the end of summer.
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Just a tight line inside hem of leading edge.
Another tight line along tips to another spoke.
Like this.
(https://i.ibb.co/84XzwWKg/Screenshot-20260522-173247.png)
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I want 2 Amps into a 14 Volt load in an 8 m/s wind. So this is what I was thinking for turbine area:
Cpt (efficiency of turning wind into mechanical energy) = 0.22 (a guess. I didn't think it would be quite 0.25, but 0.20 seemed low)
Cpg (efficiency of turning mechanical energy into electrical energy ) = 0.80 (it seems to be a number many are comfortable with, and good generators are even better)
Cpc (efficiency of converting electrical energy into useful voltage) = 0.85 (a good buck boost should be able to top that. Hopefully conservative)
2A x 14V = 28 Watts = Cpc x Cpg x Cpt x (1/2) x density x area x (8 m/s)^3
density = 1.2 kg/m^3
solve for area:
area = 28 / (0.85 x 0.80 x 0.22 x (1/2) x 1.2 x 8^3) = 0.61 m^2
So maybe a 0.61m (2 ft) diameter turbine x 1 m tall.
My previous bent wing was 0.5m in diameter and 1m tall.
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How was it constructed? It looks like there is a dowel in a sleeve along the leading edge, and the corners of the trailing edge are attached to spokes by ropes.
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Just a idea
The small sail vawt I built eons ago , starts in drag and what happens after that I'm clueless. But it got a TSR of over 3.
The sails are cheap but should last a couple years. I could build another fairly easily but I don't seem to be having any luck with alternators.
Remember this? >>>>
https://youtube.com/shorts/o5nX-MTDhCc?si=h5gx-RW91YFqd06L
https://youtu.be/YsjnzHZgvjo?si=EUwo4bBioSocHgmZ
(The wind speed meter is in mph)
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What size turbine are planning to use?
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I've been thinking it is time to finally design a VAWT that would sit "permanently" on the pole out front and actually become part of a long-term system. One that is geared for our wind conditions and the load I would like it to power. Something that would incorporate as much as I think I have learned and built to last.
I don't want to build a big generator for wind speeds we rarely see because then the battery and associated electronics have to be up-sized as well. So for starters, the rated wind speed will be relatively low. I also want to to provide at least some current much of the time, so the cut-in speed would be low too.
Wind:
Cut-in speed: 2.5 m/s
Rated speed: 8 m/s
Withstand speed: 22 m/s
My battery will not be all that large, and it won't be able to handle a lot of charging current. So the current to the load will be limited to around 2 Amps. That is within reach of many off-the-shelf DC to DC converters. If the battery voltage is around 14 volts, that means less than 30 Watts to the load at the rated wind speed. That means a fairly small turbine.
I like the Sharp style VAWT, but that has moving parts that can wear out and the Reynold's numbers are quite low when used in small VAWTs. So I think I will pass on that.
I torn between a Darrieus and a Savonius VAWT, but the Savonius is practically bulletproof. I think it would be a better long term solution. I think the "Bent Wing" approach would work well.
The generator would be direct drive for reliability and simplicity. Not sure about single or three phase yet.
This is the battery I'm looking at right now (selected with the help of ChatGPT):
Battery: https://www.walmart.com/ip/Dr-Prepare-12V-20Ah-Lithium-Battery-Built-in-BMS-4000-Cycles-LiFePO4-Battery-for-Outdoor-Fish-Finder-Radio-Lighting-RV-traveling/5527160966?wmlspartner=wlpa&selectedSellerId=101571076&selectedOfferId=73AA5AB88DE33B9882DB0D428B3EAA31&conditionGroupCode=1
The rest of the controller may need a little development yet. But I want to use a 4 switch synchronous DC to DC Buck Boost converter where the output current is controlled by a digital potentiometer connected to a micro-controller in place of the standard potentiometer, and the output voltage is regulated to what is needed by the battery. The input and output voltage current (and wind speed and turbine speed) would be monitored by the MCU which would then set the desired output current. There would be a dump load following the rectifier controlled by a PWM signal from the MCU with a crowbar dump controlled by dumb electronics for last ditch over voltage protection.