Author Topic: VAWT new proto-type (Read 251953 times)

dave ames · « **Reply #231 on:** July 05, 2011, 12:09:33 AM »

Hi GoVertical,

Thanks for the added info and pictures of the Zenbot router table..that deskCNC software looks friendly enough with good documentation available on-line.

RE: weather protection, maybe just a spray on or brush on conformal coating to the connections after you have it configured as you want? may want to give those iron rings a good paint job as well to help with any reaction between the magnets and steel..I would consider coating the magnets with something also when the final VAWT is ready for it's perch.

curious to see how you make out with the open design using the fiberglass rods

cheers, dave

XXLRay · « **Reply #232 on:** July 05, 2011, 02:39:08 AM »

you could put the alternator inside a pipe or barrel to weatherproof it.

ghurd · « **Reply #233 on:** July 05, 2011, 02:56:25 AM »

Notice the dates...

Quote from: GoVertical on July 03, 2011, 05:34:42 PM

Project Update:
After considerable deliberation I have decided that the current configuration used to place the stators between the rotors is not cost affective. The design does work, proven by the fabrication of two PMA's, one 6 inch diameter and one 8 diameter. Material cost and labor is to great. I am redesigning the PMA case using more traditional methods. The new design will allow for easier stator placement and reduce fabrication time. I will post photos in the near future. Enjoy the day.

Quote from: ghurd on August 30, 2010, 11:01:27 AM

Search the board for " multiple stators ".
It's generally not considered the best use of materials.
'link'

I doubt it is eddy currents, though I will not bet a penny on the wire gauge in the latest coils.

My bet is a basic misunderstanding of 3 phase from something you said long ago (too tired and late to look through these 233 posts, or others, to find it).
I expect it is wired improperly.
No, I do not have any idea how improper series wiring would create drag, unless it is eddy currents or shorted coils.

With your skills and tools, a more traditional PMA will certainally be successful.
G-

Watt · « **Reply #234 on:** July 05, 2011, 06:49:41 PM »

(No, I do not have any idea how improper series wiring would create drag, unless it is eddy currents or shorted coils. )

I wired a transformer once with two coils on the same round core. I energized the primary and had the secondaries ( two seperate coils ) wired wrong in series, the sparks were fantastic. lol

I think you are right, if one coil is backwards in the string of series stators, the voltage would be low and if turned long enough the problem coils will get warm I'd think.

GoVertical · « **Reply #235 on:** July 05, 2011, 11:14:36 PM »

Greetings, the local stores were unable to supply the required amount of shaft collars, so I spent the day fabricating the amount I needed. I am very happy with the results. I have to make the electrical connections and I should be testing in a few days. Cheers

GoVertical · « **Reply #236 on:** July 07, 2011, 05:36:45 PM »

Greetings, I completed the connections for a star 3 phase. When spinning by hand , there is a lot of drag. Measuring resistance between outputs the values are

L1 to L2 is 3.2 ohms
L1 to L3 is 6.0 ohms
L2 to L3 is 6.0 ohms

All these valves should be the same? Comments welcome.
I am glad that I took the time to add all the terminals.

This indicates to me that there is wiring problem. Proceeding to track down the problem. Enjoy the day.

RP · « **Reply #237 on:** July 07, 2011, 06:12:05 PM »

Looking at at the coil arrangement it seems like each stator is a complete 3 phase system rather than offset platter to platter. Is this true and if so what are the resistances between L1,2,3 on each platter before they are connected in parallel?

GoVertical · « **Reply #238 on:** July 07, 2011, 08:46:21 PM »

Greetings, I completed the connections for a star 3 phase. When spinning by hand , there is a lot of drag. Measuring resistance between outputs the values are

L1 to L2 is 3.2 ohms
L1 to L3 is 6.0 ohms
L2 to L3 is 6.0 ohms

All these valves should be the same? Comments welcome.
I am glad that I took the time to add all the terminals.

center star to L1 3.6 ohms
center star to L2 3.6
center star to L3 4.2

Meter not acting stable, difficult get a accurate reading. Could be the effect of mag rotors or it is time to buy a new meter.

It may be a problem in L3 inside one the stators. I am going disconnect all the terminal and check each stator.

I placed a hand crank on the drive shaft and there is a large mount of cogging. I now believe I may have cast one the stators opposite to the other two. If this the case I should be able to just flip it over. A lot of cogging output voltage 0.7 VAC, RPM about 60.

ghurd · « **Reply #239 on:** July 07, 2011, 09:48:32 PM »

" I placed a hand crank on the drive shaft and there is a large mount of cogging"
It can not cog at all.
'Cogging' is related to the magnetic field being unevenly attracted to the core.
There is no core, so there is no cogging.

One (or more) of the colils is shorted,
or one (or more) of the phases in incorrectly wired to the others.

I would venture to guess there is an improper connection.

artv · « **Reply #240 on:** July 07, 2011, 10:16:56 PM »

Hi Go,...If you did all the stators the same ,and accidently put one in backwards(or upside down) you should be able to just reverse the leads (on the upside down stator).....instead of taking it all apart......
If you have a coil flipped the wrong way ,..already cast ,..in any one of the stators ,...you would have to dig out the leads and reverse them,...that would be quite a chore....
The way you build stuff ,I'm sure your stators are fine ,.....spin your mill and test each phase(of each stator) by itself......leave the rest open..
The top and bottom stators will probably give a little better output than the middle,..because of the metal back plates....
The nice thing is you have the starts and ends of all the phases to switch around as you choose .....
I'm sure you know that the phase two coils are hooked opposite than the one and three..........that is the start of 1 &3 are hooked to the end of 2.........I'm not sure if that is clear ..........Ed Lenz (Windstuffnow.com) explains it really well.....
I'm sure it's a wiring problem.........that unit should give some nice output....
Keep working on it ............you'll figure it out.........artv

0

9

GoVertical · « **Reply #241 on:** July 07, 2011, 10:33:01 PM »

Hi, I wire each stator in a star configuration, each measured about 6 VAC @ about 60 RPM.
This tells me each stator is wired and cast the same. Using the original wiring scheme I added the second stator and the problem returned. I swapped L1 and L3 and measured about 3 VAC @ about 60 RPMs. Still feeling some drag and cogging. I was able to illuminate a 12 volt test light. Puzzled by the reduce voltage reading. Comments welcome.

dave ames · « **Reply #242 on:** July 07, 2011, 11:42:10 PM »

Hi GoVertical,

I'm afraid we have lost track of what this stator version is? But 6vac from each one separately at 60 rpm sure sounds promising. -> and further points to ghurds observation:

Quote from: ghurd on July 07, 2011, 09:48:32 PM

..... one (or more) of the phases is incorrectly wired to the others.

I would venture to guess there is an improper connection.

we need to be careful with this comment so as we don't confuse other readers:

Quote from: artv on July 07, 2011, 10:16:56 PM

.....
I'm sure you know that the phase two coils are hooked opposite than the one and three..........that is the start of 1 &3 are hooked to the end of 2.........I'm not sure if that is clear ..........Ed Lenz (Windstuffnow.com) explains it really well.....

although we have stacked stators these are still single layer (not overlapped) coils and there is no swapping of the starts and finish coil ends of the second phase.

best to think of it as three separate single layer 3 phase alternators on the same shaft.

<- just one guys observations here, corrections encouraged and welcome!

interesting stuff,
dave

GoVertical · « **Reply #243 on:** July 08, 2011, 10:15:22 AM »

Quote from: dave ames on July 07, 2011, 11:42:10 PM

although we have stacked stators these are still single layer (not overlapped) coils and there is no swapping of the starts and finish coil ends of the second phase.

best to think of it as three separate single layer 3 phase alternators on the same shaft.

<- just one guys observations here, corrections encouraged and welcome!

interesting stuff,
dave

Hi, using no common connection between L1, L2, L3 I was able to connect each phase between all three stators. Measured voltage @ about 60 RPM 9 VAC. So the voltage is adding up between the three plates. I am trying to fined connections for the common point. Comments Welcome.

ghurd · « **Reply #244 on:** July 08, 2011, 10:59:44 AM »

We need to know exactly how the stators are connected, and we do not.

Three stators. A, B and C.

Each is wired in star, resulting in 3 output wires. L1, L2 and L3.

That makes 9 wires.
AL1, AL2, AL3, BL1, BL2, BL3, CL1, CL2 and CL3.

What is connected to AL1?
What is connected to AL2?
etc
What is connected to CL2?
What is connected to CL3?

Again, it is not cogging.
The pulsating drag is due to circulating current between stators. (assuming there is not a shorted coil)
It will stop when the stators are wired together "properly".

"Properly" may not be the way you expect. Minute differences in the stators and phases can cause circulating currents, which is what you have.
There are simple solutions (diodes). I expect you are attempting to connect too many things together before the diodes.
G-

GoVertical · « **Reply #245 on:** July 08, 2011, 11:17:51 AM »

Hi, I found a common point. I now believe it is wired as a 3 phase star configuration, 12 coils per phase. Use a 12 volt light as a load and rotating the PMA using a hand crank measured 0.4 AC amps @ about 60 RPMs. Turning by hand is difficult. Proceeding to bench test with lathe, bridge rectifier, 12 volt deep cell load, and load controller. Will post results soon. I will also try to draw some connection diagrams. Having no other experience to relate it to I am still not sure if it is wired correctly. Using the 12 volt light as a load I was able observe a increase in voltage and current when I was able to increase RPMs. Thank you everyone for the help I am receiving.
Enjoy the day.

Madscientist267 · « **Reply #246 on:** July 08, 2011, 11:51:24 AM »

G-

Posting from phone, not trivial to quote...

Shouldn't star be wired with 4 leads?

The 3 ends and the center tap? Or are you looking at it before the taps are made?

I probably missed something here, just struck me funny...

Steve

ghurd · « **Reply #247 on:** July 08, 2011, 12:02:03 PM »

Steve,
The '4th' lead (the star point) serves no external purpose in a PMA.
Usually it is simply left embedded in the stator.
G-

GoVertical · « **Reply #248 on:** July 08, 2011, 05:57:23 PM »

Hi, found new problem, my lathe is to small. I need to fabricate floor mount for PMA and then I can try to use a 1:1 pulley and drive belt with the drill press to test the PMA. Details, details, enjoy the day.

GoVertical · « **Reply #249 on:** July 09, 2011, 10:21:58 AM »

Hi, requested diagram of how I connected coils in stators before casting. I believe they were all connected the same, but when I did the finial assembly I used the same wiring scheme that I used for the dual stator and it was very difficult to spin and had very low output. I end up connecting each phase of each stator one at time and then connected the center of the star to configure a 3 phase Star with 12 coils per phase. My oscilloscope died so off to try to find one that I use just to check the waveform. Glen's description of pulsation best describes what I am experiencing when I spin the PMA using a hand crank. The last stator connected the connection was not what I expected, which may indicate I cast the coils different from the others or it may be some other reason. I am not sure. Comment welcome.

ghurd · « **Reply #250 on:** July 09, 2011, 11:27:33 AM »

I still do not understand how it is connected.
12 coils per phase leaves at least 2 radically different configurations.

Anyway.
If it drags in a pulsating fashion with no load, it is circulating currents.
If it is wired in star, with unloaded circulating currents, then the same phase of each stator must be wired in parallel.
The paralleled stators are 'out of phase' enough to cause it.
2nd photo in reply #236 shows they are out of kilter.

Rectify each stator individually.
Then parallel the outputs.
Treat it like 3 totally separate, rectified to DC, PMAs, on the same shaft.
The result would be exactly the same, possibly better, than even if the individual stators were perfectly in phase.
G-

GoVertical · « **Reply #251 on:** July 09, 2011, 03:45:38 PM »

Hi, I am still working on the connection diagram, I will post when available. If I wired the stators as 3 individual PMA's on the same shaft that would require a higher RPM. The 12 coil per phase configuration seems to only require a really low RPM which is good for the VAWT blades design I have been working.

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

Video of manual test, enjoy the day.

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

GoVertical · « **Reply #252 on:** July 09, 2011, 06:59:20 PM »

Hi, I am puzzled by the connections between stator A and B. I tried to cast the stators the same, I had to make these connections to get a output. Comments welcomes.

GoVertical · « **Reply #253 on:** July 09, 2011, 07:07:18 PM »

unable to edit .jpeg

jaysicle · « **Reply #254 on:** July 09, 2011, 07:50:16 PM »

Hello,

Maybe your inductor set "L2" from either Stator A, or B are wound backwards?

Otherwise, if they all start left and end right - or start right and end left - it looks like A1, A2, A3 are just neutral wye/star starts, which is perfectly normal (and I am guessing your intent).

Not sure why total output would have been gone to begin with, I'd expect to see reduction with two thirds of colis on one phase cancelled though. (If they are). But not full cut.

I agree with ghurd, try IRP and maybe back up a bit and try that for each stator first to confirm.

RP · « **Reply #255 on:** July 09, 2011, 07:50:17 PM »

Here's what I would do to isolate and identify the fault:

1. Disconnect the star point from all coils on stator A.

2. Now each series string of phases Blue, Red, Green should all be the same resistance. Are they?
If not, there is a short inside one of the stators.

3. Put your load across each colored string individually and each should provide the same voltage and current as the others. Do they?
If they do not then try reversing the polarity of each stator (just on the color string you're working with) until they all produce they same.
If you cannot make them all produce the same then see if you can make any 2 series stators produce the same on all three phases. If so, the third stator has at least one reversed wired coil.

4. Now tie one end together into a star point but leave the other end unloaded. It should freewheel with no lumpiness. Does it?

5. Now try connecting your 3 output legs to the rectifiers but leave the rectifier unloaded. It should still freewheel with no lumpiness. Does it?

If you follow these steps in this order I think it will help you see where the problem is or at least it'll be helpful to the list to help see what's going on.

Watt · « **Reply #256 on:** July 10, 2011, 01:13:20 AM »

How are your magnets installed and poled with these stators?

Watt · « **Reply #257 on:** July 10, 2011, 01:34:56 AM »

Not sure how to edit my previous post. Sorry for the double reply.

I would like to add:

What is the resistance of one coil and any chance you have a south pole magnet, say in the middle rotor set, positioned in the same phase group of two north pole sets on the upper and lower rotor sets? Example that is.

XXLRay · « **Reply #258 on:** July 10, 2011, 02:46:20 AM »

If you number the coils the same way for each stator. Are the same coils alligned or is one stator possibly rotated by a coil position?

artv · « **Reply #259 on:** July 10, 2011, 07:41:57 AM »

Hi GO,...Phase #2 in those diagrams is wired backwards ..I'm assuming all stators are the same...In A stator where you have the phases tied ....the 2nd phase should be your output ,..........phase 2 in C stator (output) should be tied to A stator..
here is a pic from Eds site it is blurry but see the black dots they are outputs....Phase #2 is wired reversed

......artv

GoVertical · « **Reply #260 on:** July 10, 2011, 10:16:53 AM »

Hi, I have been able to trace the problem to stator A. It appears that I cast the coils upside down so stator A is opposite to B and C. I am going to try flipping stator A over to see if the performance improves. I will post results as soon as they are available. Thank you everyone for taking the time to help with this project. Enjoy the day.

GoVertical · « **Reply #261 on:** July 10, 2011, 12:08:42 PM »

Quote from: artv on July 10, 2011, 07:41:57 AM

Hi GO,...Phase #2 in those diagrams is wired backwards ..I'm assuming all stators are the same...In A stator where you have the phases tied ....the 2nd phase should be your output ,..........phase 2 in C stator (output) should be tied to A stator..
here is a pic from Eds site it is blurry but see the black dots they are outputs....Phase #2 is wired reversed
(Attachment Link) ......artv

Hi, I think the diagram you are showing is for a stator with overlapping coils. I am really not sure if it applies when the coils are side by side. If I am wrong please correct me. It will help clear my confusion. Comments welcome.

jaysicle · « **Reply #262 on:** July 10, 2011, 02:34:32 PM »

Hello,

What do I win?

Kidding of course, I don't win anything - I thought it was just L2 set. But you win!
Great that you were able to find it quickly.

Looking forward to output curves etc...

GoVertical · « **Reply #263 on:** July 11, 2011, 09:48:01 PM »

Greetings, project update, L1 and L2 is shorted together on stator A. Casting new stator. I am surprised I was able to find a connection scheme that was able to produce anything. I will post results when available.

News:

Author Topic: VAWT new proto-type (Read 251953 times)

Watt

Watt

Watt