Fieldlines.com || 6 Phase, yes..

Front Page - [Homebrewed Electricity-- (wind) (solar) (hydro) (steam) (controls) (storage) (mechanical)] - Classifieds - Site News
Everything - Newbies - [Remote Living-- (housing) (heat) (light) (water)] - Reviews - Diaries - Our Products

6 Phase, yes..
By fcfcfc, Section Mechanical Posted on Mon Mar 03, 2008 at 09:34:28 PM MST
Would not his produce 6 phase..??..

Hi: Would not this coil layout produce 6 phase AC?? I tried to leave some space in between so you could see where the coils came down on the other side. Yellow is phase 1, pink phase 2 etc.. then it repeats when you get to the north again, I.E. one full cycle, then the pattern continues until you get all the way around.. each sine wave would be 60 degs in front, or behind depending on how you look at it, of the other..most of the magnets solid red lines are covered up by the coils, so I used the dotted lines as visual extensions just to show you where they end.

6 Phase, yes.. | 21 comments (21 topical)

Re: 6 Phase, yes.. (3.00 / 0) (#1)
by windstuffnow on Mon Mar 03, 2008 at 04:29:23 PM MST

Looks like 3 phase to me... You could probably wire it for 6 phase but I don't see any advantage over 3 phase. Basically the same thing as shown below...

Basically 3 single phase alternators potted into one stator and each phase is off slightly.

Have Fun!

Have Fun! Windstuff Ed

Re: 6 Phase, yes.. (3.00 / 0) (#2)
by joestue on Mon Mar 03, 2008 at 05:32:12 PM MST

Yeah, that looks like 6 phase to me.

The only improvement over 3 phase would be the improved density of copper in the air gap. To my knowledge 3 phase does a fairly good job, providing the turns are overlapped, and not distributed as in the common 12/9 arrangement, which has the same density as any single phase winding. I'm sure you're aware of this, but not everyone is.

If you are interested in the benefits of 12 pulse rectification, take a look at US patent 7277302. What is not mentioned in the patent, is that particular topology requires a transformer KVA of .2p when configured as an autotransformer.
The only disadvantage is the 2 required interphase chokes.

Re: 6 Phase, yes.. (3.00 / 0) (#3)
by vawtman on Mon Mar 03, 2008 at 06:18:09 PM MST

Why the 6ph attempt Bill?

Re: 6 Phase, yes.. (3.00 / 0) (#5)
by fcfcfc on Mon Mar 03, 2008 at 08:08:49 PM MST

Hi:
The number really isn't important to me as long as its greater than or equal to 3 phase and gives me at least 400 turns per phase. My latest magnet choice, all factors considered including cost, is 1 x 1 x 2" in the main and blocking config. I am trying to wind the coils to be about 3/8" x 2/3" bundles if you wish, about 3" wide and 3" high, probably using #16 - 4 in hand in a delta config.. Remember it ends up being two coils thick on the legs, so really 3/4" thickness of copper. I can really have any number of phases I want just by varing the coil width. 2/3" width would be 6 phases, 18 coils per phase, 24 "electricial" turns per coil, 432 turns per phase. Anyway, that should allow me to gen 3KW pretty much steady without overheating. The North to South distance, like above, would be 2" with the magnet config mentioned. When I was trying to think of this whole stator concept right from the wave winding to where I am now, the goal has always been to be "all copper" at least as much as possible, no big air gaps...
The driver "thoughts" for all my crazy thinking for all aspects of this "ultimate" turbine have been:

Roof mounted.
5KW "burst capable" delivery.
Low wind, bursty and turbulent area.
Be able to instantly acquire any power from the wind that's over threshold.

Physical seeking or electrical synchronizing that compromises this is not
acceptable.

Be grid tied.
Have battery storage on line.
Generator overheating protection.
Easy future integration of PV to same system.

I mention all this to try and put this wild project in some context for everybody...
Using this type of narrower coil with the main/blocking config, will produce a very rapid change in flux for every coil. In only 4" of rotor movement, all legs of the gen will go through a whole cycle, from 10,000 Gauss to zero to 10,000 gauss to zero again!! That rapidity of flux change occuring in only 4" of rotation should produce one hell of an induced voltage, even at very low RPM's considering a 30" dia. or so rotor, I think .....LOL!!

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#11)
by finnsawyer on Tue Mar 04, 2008 at 08:42:02 AM MST

If each coil voltage lags the one before it by 60 degrees, then coil four will be 180 degrees behind coil one. This is the negative waveform of coil one, so the two really can be in phase, as you have a choice of two ways to connect them. In fact you don't want to connect them so their voltages cancel. If you bundle the coils of each of the (six) phases and bring them out you essentially must Jerry Rig them to get the output, so you lose any sense of the six phases anyway. Otherwise you just connect them for three phase, which could still be Jerry Rigged but would take fewer diodes and provide greater voltage. If you really want more than three phase go to five phase. In that case no coil voltage will be 180 degrees out of phase with any other.

Similar considerations exist for a wave winding. If wave one is just starting to pass over a north pole at its start while wave number N is just starting to pass over a south pole at its start, then the voltage waveform of wave one and N will be 180 degrees out of phase. Personally, I'm not sold on wave windings for axial flux alternators because of the problems of packing (weaving?) the waves in, particularly at the inner radius.
GeoM
[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#15)
by vawtman on Tue Mar 04, 2008 at 05:11:26 PM MST

Hi Bill
You and I have great thoughts for the vawt.I think, but its more or less until we build our units from our plans of attack nobody will take us seriosly and cant blame them.
Alot of the great thoughts are accredited to the great members here.

I wish you luck in your adventure.

Glad mines a bit simpler(may turn out not to be:>( but who knows till she's wound up.

Mark

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#18)
by fcfcfc on Tue Mar 04, 2008 at 06:06:59 PM MST

Hi: No, I agree... from the outside it is all just talk and for those that don't know me, they wouldn't know that I would not just "wing" a project of this size and that I am spread so thin it takes me close to forever to go from start to finish on these energy projects. I just think the VAWT from a common sense engineering perspective can take advantage of certain environments that HAWT's can not, do to their inherent design. Adjusting to wind direction is of course the obvious one... etc.. etc.. But at the same time I think careful "holistic" engineering is needed to produce a really worthwhile product rather than just some "thing" with a big output number slapped on it... It is not just the turbine, or the gen but the whole energy capture system that must carefully fit together...
Always fun.. can not wait till I throw the first stone on this project... then it's tick..toc..tick...toc...

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#4)
by commanda on Mon Mar 03, 2008 at 07:33:14 PM MST

I contend that it is still 3 phase.

The first and fourth coils will be 3 * 60 deg out of phase, or 180 degrees.
If you now end for end the start and finish of the fourth coil, they're now in phase.

Same with 2 & 5, and 3 & 6.

If you insist on calling it 6 phase, and rectifying seperately each phase, all you're really doing is a jerry-rig rectification scheme.

Consider a Fisher and Paykel. It has 42 coils. This does not make it a 42 phase machine. You can seperate the coils from each other, and rectify each individually. It's still only a 3 phase machine. (Ignoring for now the later magnet arrangement which produces a 7 phase machine).

Because the 180 deg phase shift can always be inverted and made in phase, any poly phase machine will always have an odd number of phases.

Amanda

Re: 6 Phase, yes.. (3.00 / 0) (#6)
by fcfcfc on Mon Mar 03, 2008 at 08:23:44 PM MST

Hi Co..:
This has had me "nuts" thinking about this. I thought of that, that is, if coil four was hooked to one but either reverse wound or start to end if you wish and the same one for 2 & 5 and 3 & 6, YES, then the current directions match so the "pairs" operate as one winding BUT, BUT, this means that all the pairs or phases have changed with only half of the distance covered getting back to North again. It would be like 3 ripples in only 1/2 of the cycle...yes..no ?? my brain is in a knot over this.. sometimes I think I "see it" but then no..

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#14)
by joestue on Tue Mar 04, 2008 at 03:27:47 PM MST

-Just had one hell of an AH HA moment.
I take back what I said earlier.

Amanda's right, the phase shift is 60 degrees, and you can't have an even number of phases.

If you want 6 phase operation, build one set of coils with 58/100 turns and connect in WYE, with the 100 turn coil in Delta. you will get a 30 degree phase shit.

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#17)
by fcfcfc on Tue Mar 04, 2008 at 05:45:21 PM MST

Hi: No, three phase is fine, I am just having a hard time in my head seeing how the phases are spread equally across when you only traverse half way across the distance between like pole to like pole. As I continue to think about this, I think what is happening is that a full cycle is only still made when a given coil has made the trip once from like pole to like pole but since it is being done in pairs, I.E. 1-4, 2-5, 3-6, it has the effect of halving the distance... boy this is difficult trying to visualize how a physical separation of 60 degs produces 120 degrees of electrical separation...

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#19)
by Lumberjack on Tue Mar 04, 2008 at 08:13:25 PM MST

Well assuming equal coil spacing coil one will go positive while coil 4 goes negative. A different way to see it is to realise the extra three coils will run exactly opposite of the first three.

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#7)
by ghurd on Mon Mar 03, 2008 at 09:15:53 PM MST

It is 3 phase. Trust me and everyone else or your head will explode.

I made some 4 magnet, 6 coil, PMAs. A bit different but close enough.
My head almost exploded tring to figure it out, and it is 3 phase.
G-
Ghurd.info

Re: 6 Phase, yes.. (3.00 / 0) (#8)
by Flux on Tue Mar 04, 2008 at 12:47:00 AM MST

It's NO phase until you put some wires to connect it.

Intrinsically it is a 6 phase layout if you take the starts from each coil as the phases. In real life it is the layout uses in all 3 phase machines wound as a 2 layer winding ( much more common in Europe).

For 3 phase you take the connections as each coil progresses as A, C reversed, B.

In other words you take the phase connections from every 120 displaced coil if you want 3 phase. Take every coil if you want 6 phase.

The concentric coil convergent pole winding is more common in N America, this configuration is by far the most common in the rest of the world.

Don't get hung up on the strange 12 pole 9 coil arrangement seen here, it just doesn't exist in the real engineering world. It is a useful dodge that works well with axial machines where winding space is very restricted in the centre. You will never find commercial machines wound that way.

Flux

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#13)
by fcfcfc on Tue Mar 04, 2008 at 12:42:24 PM MST

Hi: I guess it would be 3 phase if I want.. I will just reverse wind the second coil in each pair for all three sets (phases) that it would make. Then you have 1-4, 2-5, and 3-6 with 4,5 and 6 wound in the opposite direction. I will cut my copper in half and thin the stator with 12 turns per coil but 36 coils per phase still at 432 turns per phase. I should then be able to easily have a 3/8" or 1/2" thick stator and a rotor gap of 1/2" or 5/8". With the 1" thick neos I will easily get my 1T field at that gap. I just wish I could see in my head how the 3 waves will fill out evenly (at 120 degs) a full cycle even though any one of the coils moves only half way from like pole to like pole.... I definitely will build the rotors first and do coil section samples for testing, before I dare make the whole stator...
Thank you everyone...once again...

[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#9)
by tecker on Tue Mar 04, 2008 at 04:20:54 AM MST

You have to be aware there will be cancellation from the coil release in a clustered up star or misaligned delta . An AC mess like that is common , current is blocked and charges are limited . Of coarse if you work with single phases density is an advantage.

Re: 6 Phase, yes.. (3.00 / 0) (#10)
by Aule Mar on Tue Mar 04, 2008 at 08:15:38 AM MST

I like your design goals, and plan on following your development.
It will be interesting to take a proven design and make some radical changes
just to see how much it can be improved.

I've had a thought that, I haven't seen here yet, and it addresses one
your design goals (7 Generator overheating protection.) I hesitate to post
it here, under a subject line of "6 Phase", But it does tie into your
design.

As you try to pull more power out of these axial generators, overheating
seems to become a big problem. Especially when the coils are potted up and
the heat can't get out. I figure if there was ventilation holes drilled
into the magnet rotor plate the magnets would act like fins on a fan and
force cooling air through the coils. The pict is just a conceptual design.

I know the whole unit is up in the wind, but those coils are behind the
rotor disk and pretty much shielded from the wind.

Aule Mar

Re: 6 Phase, yes.. (3.00 / 0) (#12)
by finnsawyer on Tue Mar 04, 2008 at 08:49:01 AM MST

"I figure if there was ventilation holes drilled
into the magnet rotor plate the magnets would act like fins on a fan and
force cooling air through the coils. The pict is just a conceptual design"

This has been discussed in the not too far distance past. At the time I suggested drilling the ventilation holes at an angle. Coupling that with curved fins on the backside of the rotor would force air into the space between the magnets that would then flow outward providing the cooling. You need to get a little more aggressive than what you show.
GeoM
[ Parent ]

Re: 6 Phase, yes.. (3.00 / 0) (#16)
by Lumberjack on Tue Mar 04, 2008 at 05:12:41 PM MST

It is 6 phase if you want it to be. It really depends on how you choose to recitfy it. If your going to DC then just put a bridge rectifier on each phase and then tie them together afterwards. This will also work for any other number of phases you want.

Re: 6 Phase, yes.. (3.00 / 0) (#20)
by Ungrounded Lightning Rod on Thu Mar 06, 2008 at 03:10:37 PM MST

phase would have 12 coils per magnet pair (or some less dense equivalent).
coils the way you drew them means coils 1, 3, and 5 are the same as coils 4, 6, and 2 with the start and end terminals swapped. That's 3 phase.

Re: 6 Phase, yes.. (3.00 / 0) (#21)
by joestue on Thu Mar 06, 2008 at 03:59:48 PM MST

You can't have an even number of phases!

12 coils would work out to 4 sets of 3.

[ Parent ]

6 Phase, yes.. | 21 comments (21 topical)

Menu

� create account
� How to use the board
� FAQs
� search the board
� Google search the board

Login

Make a new account

Username:

Password:

Total Views

��222 Scoop users have viewed this posting.

Related Links

� magnet
� Also by fcfcfc

You must be a registered user to post here. It's easy and free, and the link is on the upper right side of your page.
All trademarks and copyrights on this page are owned by their respective companies. Postings are owned by the poster, but may be deleted or moved at the ADMIN's sole discretion. The Rest � 2009 Forcefield.
You can Email the board ADMIN here. PLEASE include the username you signed up with!