Questions about PMG

[marcio]

I´m sorry if is a newbie question , but... english isn´t my language and so I´ve lots of trouble undertanding too many info while searching with the google tool...

Asuming that I will make a PMG with dual rotors , 24 total magnets , what magnet size will give me more power?

1,5" x 0,5" x0,25" N38 grade

or

1" x 0,5" x 0,5" N40 grade

I think the first one is more powerfull, right?

And how will a single rotor with 24 magnets will compare to a double rotor with 12 magnets in each rotor?

Thank you very much!

Marcio

[BrianK]

what is your first language?

 .

[richhagen]

I'm no expert on this, but in my opinion, although you have a larger volume of magnetic material in the second 1x.5x.5 magnet, and if graded correctly are stronger, I think something like 14%, the 1x.5x.25 magnets would seem to me to be a better shape for a dual axle machine.  It would allow for longer coils of the same width. Rich Hagen

[jimjjnn]

Go for the N40 grade. Much better magnets.

[jimjjnn]

Rich,

Sorry I stepped on your toes. You got it perfect. Guess I should read before responding.The N40s are much better.

[marcio]

sorry, i forgot ro mention that I live in southern Brazil , my first language is portuguese.

[marcio]

Thanks!

Any thoughts about the last question?

[PHinker]

I think the following would probably be the order :

   * 24 magnets, single rotor, silicon steel laminated stator core   * 12 magnets, dual rotor (total 24 magnets)

   * 24 magnets, single rotor, no ferrous material in stator core

   Keeping all other things equal (i.e. wire size, number of coils, number of turns per coil, etc.).  Of course, you might make other changes depending on whether or not you have 12 or 24 poles on your rotor which would also effect the performance.

Paul

[PHinker]

Ack!  That didn't come out very readable.

1.  24 magnets, single rotor, silicon steel laminated stator core
   
2.  12 magnets, dual rotor (total 24 magnets)
   
3.  24 magnets, single rotor, no ferrous metal in stator core
   
   

Hope that comes out.

Paul

[Aaron]

Good luck with that alternator down there in Brasil, beleza!

I have a question  related to this discussion.PHinker kind of got me wonderin'......I'm about to build a dual rotor pma using 24 of those wedge shaped neos from Ed@windstuffnow. Judging from the otherpower site's postings I figured a dual rotor machine was more powerful. Is this not the case?  Am I better off just making a single rotor with the 24 mags? I was planning on a 9 coil 3-phase design with #11awg wire. Not sure how many windings yet. Dual or single and why if anyone knows?

Aaron