Serious HES derivative project proposal

[floodrod]

Perhaps a 3PH generator is a bit too involved to start with? This image is a possibility. A stator setup like this would be similar to 4 Lingens. We would lose the benefits of 3 phases and drop 4 coils from the stator, but at this point all we are shooting for is a viable method with minimal parts.

My statement may hold no bearing, but attached is the Holcomb magnetic domain image that they use. It shows divisible by 2.

Nine poles would give three phases nicely, but the magnetic domains would not be divisible by 2, thus forcing two same polarities to be next to each other.

Three-phase should also be possible using six poles. Six groups of six poles to make three phases that are divisible by two. But then it deviates from Holcomb's image in that we have opposite polarities on either side from each other, where his image shows like poles on either side.

If we wish to duplicate Holcomb's exact alignment with this rotor, I think our option would be four groups of nine coils.  This would give us a duplication of his image where we have four polarities, and the two across from each other are alike. But then we lose a phase.

Does all this matter? I don't know. Does he use a deceptive image to hide something, I don't know. These are just my observations though

[bistander]

Bistander,

Ok you've made your point. Enough already. If we were trying to squeeze every last joule out of it, there never has been any doubt that electrical steel is better, and I couldn't care less where Dr. Holcomb claims the energy comes from.

Hi Cadman,
So you're not worried about H_c , but B_sat may have a direct bearing on magnetic performance. That is the saturation flux density of the material. Have you any idea of the value for the powdered Fe bonded mixture you intend to use? It could be 50% or less than that of the electrical steel in the stator. Knowing this ahead of time will allow you to compensate with the design of the shape of the rotor laminate, as you call it. Specifically to make the rotor tooth width sufficiently larger than the width of the stator tooth. Not the tooth tip, but the tooth body width. The other "tight spot" in the rotor portion of the magnetic circuit would be the back iron. Because of the circular area aspect, more real estate is available outside the air gap so features can be thicker (to reduce flux density) without sacrifice of too much winding space. This also will make the parts more ridgid and easier to fabricate and wind.
Take it or leave it. Easier to move a line on the drawing than to remake the part.
bi

[Cadman]

My statement may hold no bearing, but attached is the Holcomb magnetic domain image that they use. It shows divisible by 2.

Nine poles would give three phases nicely, but the magnetic domains would not be divisible by 2, thus forcing two same polarities to be next to each other.

Three-phase should also be possible using six poles. Six groups of six poles to make three phases that are divisible by two. But then it deviates from Holcomb's image in that we have opposite polarities on either side from each other, where his image shows like poles on either side.

If we wish to duplicate Holcomb's exact alignment with this rotor, I think our option would be four groups of nine coils.  This would give us a duplication of his image where we have four polarities, and the two across from each other are alike. But then we lose the three phases.

Does all this matter? I don't know. Does he use a deceptive image to hide something, I don't know. These are just my observations though

Thanks for that. I was thinking the number of 3 phase coils had to be divisible by 3.

See, I told you I didn't know anything about 3 phase motor building. 

[Cadman]

Hi Cadman,
So you're not worried about H_c , but B_sat may have a direct bearing on magnetic performance. That is the saturation flux density of the material. Have you any idea of the value for the powdered Fe bonded mixture you intend to use? It could be 50% or less than that of the electrical steel in the stator. Knowing this ahead of time will allow you to compensate with the design of the shape of the rotor laminate, as you call it. Specifically to make the rotor tooth width sufficiently larger than the width of the stator tooth. Not the tooth tip, but the tooth body width. The other "tight spot" in the rotor portion of the magnetic circuit would be the back iron. Because of the circular area aspect, more real estate is available outside the air gap so features can be thicker (to reduce flux density) without sacrifice of too much winding space. This also will make the parts more ridgid and easier to fabricate and wind.
Take it or leave it. Easier to move a line on the drawing than to remake the part.
bi

Thank you bistander, 

I have no real idea what the B_sat of the laminate will be ahead of time. I just assumed for a starting point the cross section of the rotor teeth and back iron would need to be close to twice the section of the stator teeth as I can get just to make the permeability better match the stator electrical steel. Working with the powdered iron is going to take some trial and error. There's no way around that when it can't be calculated ahead of time.

It will never be as good as electrical steel but I do know the remanence is much lower than A36 and 1008 low carbon steel, and I believe the coercivity is too.

Who knows, we may get lucky on the first try.

[floodrod]

Thanks for that. I was thinking the number of 3 phase coils had to be divisible by 3.

See, I told you I didn't know anything about 3 phase motor building. 

I assume we have 3 criteria's:

1. 3 phase preferably
2. Like polarities opposite from each other as the holcolmb image
3. And even pole number so we can properly alternate polarities without having 2 polarities next to each other.

Then I think the only configuration that works with a 36 pole stator is 3 coils in series per pole.  12 poles.
Then 4 poles would connect together per phase. 

If we want to do opposite poles across from each other- there is other options.  I just don't understand all the dynamics yet..

On a side note- Cadman- when you get time-can you explain the pickup part as you envision it?  I have been reading the Holcolmb thread somewhat,  but so many ideas and predictions have been pitched I would like to hear your breakdown and plan.