Author Topic: VAWT new proto-type (Read 251915 times)

GoVertical · « **Reply #165 on:** May 15, 2011, 08:43:59 AM »

Greetings, test results disappointing. Very low output. I am fabricating new stators. 4 in hand, 22AWG.
Enjoy the day, Cheers

GoVertical · « **Reply #166 on:** May 18, 2011, 04:10:15 PM »

Greetings, I was thinking about my less post and I may have misspoke. I made some test coils using 22 AWG.

1 in hand @ 200 turns output @ 200 RPM = 1.3 VAC
2 in hand @ 100 turns output @ 200 RPM = 0.7 VAC
4 in hand @ 50 turns output@ 200 RPM = 0.3 VAC
8 in hand @ 25 turns output@ 200 RPM = 0.16 VAC

I apologize to the forum and anyone reading my last post.

Project update:

Fabrication method established.

Currently fabricating new blade rotor assembly.

6 inch diameter is to small for direct drive, will require gearbox or a belt or chain drive.

The best test results was with the 8 inch PMA. Adding third stator to 3 phase configuration.

Enjoy the day.

Tritium · « **Reply #167 on:** May 18, 2011, 06:50:02 PM »

If the gap between the coils and magnets is as big as it looks then it is a definite problem and needs to be much narrower.

Thurmond

willib · « **Reply #168 on:** May 18, 2011, 09:09:01 PM »

Hi Goverticle,
The gap is one thing , but your magnet spacing is to big
Have a look at this
http://fieldlines.com/board/index.php/topic,145436.0.html

It tells how to get your magnet spacing and your coil size correct.

GoVertical · « **Reply #169 on:** May 18, 2011, 10:23:40 PM »

Greetings, because I was trying a small diameter rotor I wired the stator coil legs to be ½ the magnet diameter.

http://www.otherpower.com/images/scimages/5441/Single_Phase.jpg

Please refer to the bottom image. The configuration works well for single phase, but the diameter of the stator limits the size of the coils and magnets and requires a higher RPM to reach a 12 volt cut in for a 3 phase. The 8 inch 3 phase I was working on with a single stator reached the 12 volt cut in at 800 RPM and when I added the second stator the 12 volt cut in occurred under 200 RPMs. I plan on adding a third stator to the 8 inch 3 phase which I believe will reduce the RPM cut in even lower. I am also working on the new blade rotor configuration, I am hoping to have it completed by Monday. Than I can test it with the PMAs I have and try to determine if I need to make the blades larger. Matching the PMA to blades will be the next big challenge. I am putting the 6 inch PMA on the back burner for now.

I do have one question is it better to have larger magnets and fewer coils for a set diameter or more smaller magnets and coils for the same set diameter? I made a test coil with 18 AWG at 100 turns and the output was 0.7 volts @ 200 RPMs using the rotors with the ¾ inch magnets. Using 1 inch magnets I can fabricate a 3 phase stator with 3 coils per phase or I can use ¾ diameter magnets and have 4 coils per phase. Is it possible to determine which configuration would be better? Mainly the goal at this point is to have the highest output at the lowest RPM for a 8 inch diameter. Comments welcome.

GoVertical · « **Reply #170 on:** May 19, 2011, 11:10:09 PM »

Greetings, I have all the parts to fabricate a 8 inch three stator, 4 rotor PMA using the ¾ magnets. The stators will be wired using the traditional method creating 4 coils per phase on each stator. So when all the stators are wired together it will be 12 coils per phase. This should work for a direct drive. I should know more in a few weeks. Enjoy the day.

Madscientist267 · « **Reply #171 on:** May 21, 2011, 08:34:14 AM »

Good luck man... I don't know about you, but I hate repeating myself...

You know, that feeling you get when you realize that you've gone horribly wrong?

Yeah, that one.

Gets worse with more money involvement...

Been there done that, got the T-shirt and burned it... too many times to count.

Steve

GoVertical · « **Reply #172 on:** May 21, 2011, 09:24:15 AM »

Greetings, when I started the project I had no idea of a few key relationships and no experience relating the numbers to real life operation. So far I am happy with the fabrication method and the materials being used. Stacking the stators and rotors does work. The smaller diameter PMA needs a gearbox, 4:1. I need to complete the blades and determine if it will reach the RPMs needed to operate the 8 inch as a direct drive at a low wind speeds. I can expand the blade size if needed. I am working on the blade rotor now and should know more in a few days. Its all in the details. Enjoy the day.

GoVertical · « **Reply #173 on:** May 21, 2011, 10:40:54 AM »

Greetings, redesigned hub and spoke rotors. Fabricated drill jig for spokes. Cleaner and easier to fabricate. Spins well, should be a stable platform for the blades. Enjoy the day.

Madscientist267 · « **Reply #174 on:** May 21, 2011, 11:01:06 AM »

I wanna come hang out at your house.

You got all the cool toys.

Wifey says I shouldn't be jealous, but I can't help it.

I WANNA PLAY!!! LOL

Steve

GoVertical · « **Reply #175 on:** May 21, 2011, 01:29:05 PM »

Greetings, completed one blade. Laying flat it measures 3x2. I have to attach the hinge assemble and flex the blade to form the arc shape between the spokes. I am using a CAD program to determine hole locations. If anyone can suggest a good blade angle to start with please let me know. Comments welcome. Enjoy the day.

GoVertical · « **Reply #176 on:** May 21, 2011, 01:33:05 PM »

I forgot to insert photos. Enjoy the day.

GoVertical · « **Reply #177 on:** May 21, 2011, 01:38:23 PM »

Quote from: Madscientist267 on May 21, 2011, 11:01:06 AM

I wanna come hang out at your house.

You got all the cool toys.

Wifey says I shouldn't be jealous, but I can't help it.

I WANNA PLAY!!! LOL

Steve

Free help, sounds good. Stop by anytime, I will put you to work.

GoVertical · « **Reply #178 on:** May 22, 2011, 12:28:49 PM »

Greetings, removable pin and hinge configuration greatly reduced personal stress during assemble. The blade attached very easy to the spoke. The blade angle is not correct and I am sure the size of blade will change, but I am on the right track. Enjoy the day.

GoVertical · « **Reply #179 on:** May 24, 2011, 12:09:11 AM »

I had all the parts for a simple experiment. Metal back rotor verses No Metal rotor. Yes there is a monster air gap. The RPMs where the same in both cases, same coil, same air gap. The open circuit output was the same in both cases. The one thing I did find is that the metal backed rotor does contain the magnet field so there is no reduction of RPMs that could be caused from the magnet field pulling on metal parts near the rotor.

dave ames · « **Reply #180 on:** May 24, 2011, 12:57:31 AM »

Greetings GoVertical,

Thanks for the testing..I would have expected a very large difference from what I have seen while goofing around with this stuff.

Can we please confirm your magnet arrangement?
Rotors in attraction?
Each rotor with the magnets alternating North/South/North/South..Etc?

This just feels wrong..

kind regards, dave

GoVertical · « **Reply #181 on:** May 24, 2011, 06:40:03 AM »

Hi Dave, yes the rotors are attracting each other. The magnets are N,S,N,S. The meter read out was deviating + - a few thousandth of a volt and that was the readout when I took the photo.

Tritium · « **Reply #182 on:** May 24, 2011, 04:55:13 PM »

Your gap is SO large that most of the flux is shorting from adjacent magnet to adjacent magnet on the same rotor rather than crossing the gap as required.

Note: I see Flux already told you this in the other thread you posted it in.

Thurmond

GoVertical · « **Reply #183 on:** May 24, 2011, 11:39:34 PM »

I decreased the air gap as much as possible. I repeated the same test again several times with and without metal back on the rotors. Volt meter readout was not sable with a deviation of + - .005. The open coil voltage increased as a result from decreased air gap to 0.90 AC. I used the same coil, same air gap, same RPM each time I ran the test with and without the metal backing. I was only able to detect a slight increase in voltage of approximately a few thousandths of a volt when using the metal backed rotors.

dave ames · « **Reply #184 on:** May 25, 2011, 10:36:01 AM »

Cheers Go Vertical,

Thank you for the additional testing. It's interesting that the advantages of an iron backing are less pronounced with these "rod" type magnet geometries

..now I'm wondering if there is a sweet spot somewhere in the airgap where the difference shows up? pretty cool observation none the less.

somehow we have this discussion overlapped in another thread ..
http://fieldlines.com/board/index.php/topic,145433.msg988604.html#msg988604

dave

GoVertical · « **Reply #185 on:** May 25, 2011, 05:57:41 PM »

Hi, the test results may be very different with other shape magnets. I found the deceased air gap to have the greatest increase on the output at a constant RPM. The benefits of having metal backed rotors on the top and bottom rotors of my project are that it does contain the magnetic field and decreases any drag on the rotor speed caused from the magnetic attraction to any near by mounting metal hardware. They are also very useful for mounting the magnets to the rotors. I posted the test results in the other thread first and then again in my diary. Enjoy the day.

GoVertical · « **Reply #186 on:** May 28, 2011, 09:33:21 AM »

http://www.youtube.com/watch?v=gFzUGH_4RGw

Greetings, I completed the assembly of new blade rotors. No wind today, same thing happened last year. Cheers

willib · « **Reply #187 on:** May 28, 2011, 03:19:56 PM »

Quote from: GoVertical on May 24, 2011, 11:39:34 PM

I decreased the air gap as much as possible. I repeated the same test again several times with and without metal back on the rotors. Volt meter readout was not sable with a deviation of + - .005. The open coil voltage increased as a result from decreased air gap to 0.90 AC. I used the same coil, same air gap, same RPM each time I ran the test with and without the metal backing. I was only able to detect a slight increase in voltage of approximately a few thousandths of a volt when using the metal backed rotors.
(Attachment Link)
(Attachment Link)

I wasn't going to say anything, twice i wasn't going to say anthing.
but everytime i look at the second picture in this post , it is as plain as day.

Your magnets are too far apart.

As one magnet is over one side of your coil the other magnet has allready passed over the other side.
Thats not the way it should be.

Two magnetic poles should pass over each leg of a coil ' at the same time'.
I wrote a little topic called " alternator design" in the wind section.
have a look at it.

GoVertical · « **Reply #188 on:** May 28, 2011, 05:19:23 PM »

Hi willib, Thanks for the feedback. I am using the third example. Coil leg width is Â½ the magnet diameter. I finally have the turbine mounted outside and I should be able to road test in a few days. Thanks again and enjoy the day.

willib · « **Reply #189 on:** May 28, 2011, 05:34:22 PM »

Nice looking blade rotors. BTW

They look like they will really catch some wind.

Did you decide not to anchor your VAWT at the top?
just curious

GoVertical · « **Reply #190 on:** May 28, 2011, 06:19:24 PM »

Greetings, I was able to find the parts that allowed me to add the second hub and spoke assembly, that plus I laminate each side of the blade with aluminum making it a very stable blade rotor configuration. The blade size can be easily changed to find the optimum size and position angle. I do not know what it will do at higher wind speeds. This was fabricated to reveal any problem areas. It is much easier to fabricate then earlier designs. I tried to keep the mass as centered as possible, it will be interesting to see if the center bearing shaft can handle the force of the blades at high wind speeds. I should know more after the road test. Enjoy the day.

GoVertical · « **Reply #191 on:** May 31, 2011, 11:20:30 PM »

http://www.youtube.com/watch?v=Q8_3xPxQc-M

http://www.youtube.com/watch?v=Q8_3xPxQc-M

No wind today. I always wanted to make a music video. I have no plans to quick my job. Enjoy the day. Just for fun.

GoVertical · « **Reply #192 on:** June 01, 2011, 05:46:47 AM »

Quote from: GoVertical on May 31, 2011, 11:20:30 PM

http://www.youtube.com/watch?v=Q8_3xPxQc-M

http://www.youtube.com/watch?v=Q8_3xPxQc-M
I have no plans to quick my job.

Should read I have no plans to quit my job. Enjoy the day.

Bruce S · « **Reply #193 on:** June 01, 2011, 11:48:34 AM »

Is that a Sepia filter on the camera? or sundown haze?
Wings still looked pretty turning slowly

have Fun!

Madscientist267 · « **Reply #194 on:** June 01, 2011, 01:19:01 PM »

Not bad...

I'll take a stab and say that the turbine is incredibly efficient then...

While the effect may be immeasurable, in some form or another, even sound waves from the guitar will have an effect on the farthest reaches of the universe, and maybe beyond, depending on your belief system. Everything gets turned into heat eventually.

Therefore, I propose that being as close as it was, since there was no wind, the turbine was guitar powered!

Very efficient indeed!

I like it. Looks like the tried and true Newton's "extra" law about no wind after a turbine is erected holds true!

It will come.

Steve

zap · « **Reply #195 on:** June 01, 2011, 02:06:55 PM »

Quote from: Bruce S on June 01, 2011, 11:48:34 AM

Is that a Sepia filter on the camera? or sundown haze?

I think he just pointed the camera at one of those gold colored reflective "yard globes"(gazing ball, lawn ball, garden ball, gazing globe, mirror ball... heh)?

GoVertical · « **Reply #196 on:** June 01, 2011, 04:38:35 PM »

Hi, yes the camera was pointing at a gold tint yard globe. I should of tuned up before I started recording. I finely have the required parts to mount the blade rotors to the test PMA. I should be able to post results in a few days. Enjoy the day.

REdiculous · « **Reply #197 on:** June 02, 2011, 12:38:23 AM »

near the end (2:35) there's a single drop of water that kinda rolls down the ball like a tear..aww.

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Author Topic: VAWT new proto-type (Read 251915 times)