Why do two drive coils draw less power and create more RPM ?

[Magluvin]

Very cool.   In the speaker example, the output rises as the input is the same. In your example it is the same as adding speakers in series, and the impeadance(resistance) increases pulling less current from the rated amp, yet still achieving the same output.  ;]

So if you had 16 coils, will the input be near .24w at 1400rpm?    ;]


32?  .14w?  1400 rpm?   ;]

Now, how do we apply this seemingly multiplying function to gen coils? ;]

Mags

Edited to change 140 to 1400   =-]  And again ma to w  ;]

[Magluvin]

Ya know,  give this a try for the fun of it, when you wake tomorrow. 

Put a freewheel diode on each coil, of the 4 you have now.

Just have the diode polarity so that it doesnt conduct during input, but when the input is disconnected, the diode will freewheel the coil to get a longer push. ;]  trust me, I been doin it for a while now.

You should see at least 200 rpm increase at .97w  And actually, if you would report your rpm and watt findings, Ive seen a lowering of the input using this method.  ;]

Oh  I meant to say watts instead of ma in the above post.  Sorry

Mags

[DeepCut]

I don't understand. I just googled freewheel diodes and understand how they use energy from inductive loads, but i can't see how i would connect one to each coil.\

*EDIT ADD*

I'm being dumb aren't i ? There's only one place i can stick the diodes, in between the coils !

OK will try then post results.

[DeepCut]

OK i tested it with just one diode (1N4001) in between the last two coils in the series and my current draw went down to .052 but my RPM went down as well.

Maybe i'm doing it wrong, i just connected the diode in series with two of the drive coils ?

This is what i don't understand :

"Just have the diode polarity so that it doesnt conduct during input, but when the input is disconnected, the diode will freewheel the coil to get a longer push."

If i have the diode the other way round then no current will conduct and there is no rotation at all, or do i need to add more than just a diode ?

[gyulasun]

Hi Gary,

The diodes come in parallel with the coils, one diode per one coil, so 3 diodes if you have already 3 coils.
And on the diode polarity: Magluvin wrote it,  if you did not get it: a diode in parallel with a coil should see reverse bias polarity when you switch ON the coil.  This way the spike from the collapsing field at switch-off will be directed back to the coil and it maintains for little time the coil current. This means that you can reduce the ON time of the switch a little so this
reducement is a benefit in input power.

Gyula

PS: in my previous post I wanted to write torque rather than RPM when I referred to RPM which increases as the number of input coils and the number of permanent magnets are increased. RPM also increases a little though.