Author Topic: generic coil shape question  (Read 2400 times)

0 Members and 1 Guest are viewing this topic.

gww

  • Hero Member
  • *****
  • Posts: 762
  • Country: us
generic coil shape question
« on: July 04, 2012, 04:44:32 PM »
If a coil was made round with the center (no wire) hole being aprox. 2" round and you used a 2"x1" rectangle magnet, how would this affect the magnetic flux.  Would it be the same or weaker. 

Watt

  • Guest
Re: generic coil shape question
« Reply #1 on: July 04, 2012, 04:51:02 PM »
If a coil was made round with the center (no wire) hole being aprox. 2" round and you used a 2"x1" rectangle magnet, how would this affect the magnetic flux.  Would it be the same or weaker.

If you have a scope available, give it look.  You won't notice much difference charging a battery though. 

gww

  • Hero Member
  • *****
  • Posts: 762
  • Country: us
Re: generic coil shape question
« Reply #2 on: July 04, 2012, 04:55:46 PM »
Watt
low budget, no scope.
Thank you for your answer.  I was kind of hoping it would have been weaker as I replaced ferrits with neos. you have answered my question though.
thanks
gww

Watt

  • Guest
Re: generic coil shape question
« Reply #3 on: July 04, 2012, 04:59:29 PM »
Watt
low budget, no scope.
Thank you for your answer.  I was kind of hoping it would have been weaker as I replaced ferrits with neos. you have answered my question though.
thanks
gww

Replacing the ferrite with neos will produce more voltage at the same rpm.  Coil shape refining will produce the same results to a point.  Others here have more experience on this topic and by all means, wait a bit for others to chime in. 

gww

  • Hero Member
  • *****
  • Posts: 762
  • Country: us
Re: generic coil shape question
« Reply #4 on: July 04, 2012, 05:22:03 PM »
Watt
Flux has responded in a different post on options of making my specific turbine posibly a decent one.  I just didn't know if I might not be one step ahead in that prosses due to coil shape.

 Thought maby this created a simular situation as widening the gap.
 I made a 48v that called for 320 turns if thing were equal then 24v would be 160 turns and 12v would be 80 turns I wound this one with 120 turns thought maby the shape would bring it closer to 80 turn coil.  The answer will be what it will be.  hope to here from more athough I believe you are right.  thank you
gww

Flux

  • Super Hero Member Plus
  • *******
  • Posts: 6275
Re: generic coil shape question
« Reply #5 on: July 05, 2012, 03:18:48 AM »
To link all the available flux of a magnet you need turns bigger than the magnet. If you have rectangular magnets, any turns of a coil bigger than the magnet will link all the flux. If the inner hole of a rectangular coil is the size of the magnet you use all available flux.

Any smaller coil or using a round coil with rectangular magnets will mean that at no time will you link all the m,agnet flux so from a purely voltage point of view you will loose out but that is not the whole story, the shorter turns will have less wire and less resistance so although you have less than the ideal voltage you may still have a more favourable volts/resistance ratio.

It really is not too easy to guess how these things interact but it seems from results obtained that you can bend the rules a lot.

Using round coils in your case almost certainly does equate to the same thing as opening the gap but the reduction in resistance could possibly mean that you may need to add series resistance if you can't get the thing out of stall after increasing the air gap  to the point where your cut in speed is in the 7 to 8 mph region.

Flux

gww

  • Hero Member
  • *****
  • Posts: 762
  • Country: us
Re: generic coil shape question
« Reply #6 on: July 05, 2012, 04:50:45 AM »
Flux
thank you agin.  this board and you specifically are speeding up my learning curve.  That is if I'm not letting my pre-conseived  notions decieve me.  I re-read everything several times and I believe some of it is sinking in.

Thank you watt

gww