Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Custom Search

Author Topic: Why do two drive coils draw less power and create more RPM ?  (Read 13518 times)

DeepCut

  • Hero Member
  • *****
  • Posts: 640
Hi, another noob questoin from me i'm sure someone here can explain it.

I am driving a standard Bedini SSG circuit from a DC power supply.

With one drive coil attached i was drawing 18V @ 300mA and getting 1400 RPM.

I attached a second drive coil in series with the first and i was drawing 18V @ 150mA and getting 1485 RPM.

Questions :

1. Why is the rotor spinning faster ?

2. Why has the input amps been cut by 50% ?

Any education greatly appreciated :)


Cheers,

Gary.

Cherryman

  • Hero Member
  • *****
  • Posts: 642
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #1 on: July 04, 2011, 10:30:59 PM »
Maybe the old saying "Divide and Conquer" does not only work in politics  ;)

Magluvin

  • Hero Member
  • *****
  • Posts: 5884
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #2 on: July 04, 2011, 10:55:18 PM »
Considering what we discussed at OUR, is there a possibility that we can have just 1 or 2 gen sets and the rest are drivers. ;]

Mags

gyulasun

  • Hero Member
  • *****
  • Posts: 4117
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #3 on: July 04, 2011, 11:11:35 PM »
Gary,

The input current is reduced to half value because it 'sees' double the DC resistance and double the AC impedance wrt the single coil case.

On your first question: Cherryman gave a good answer I believe,  The more permanent magnets you use in such pulse motors and the more input coils you let interacting with those magnets, the higher the rpm may climb up.   Putting it otherwise: the more flux you enter into the setup (by using the many permanent magnets) the better the efficiency of the input power usage becomes.  I am not saying this input efficiency may increase beyond 100% by this 'divide and conquer' method because I have not tried it but it is sure it increases as said above.  (Years ago member Ian showed this in a youtube video.  See his posts here: http://www.overunity.com/index.php?topic=1754.msg31932#msg31932 )

Gyula

DeepCut

  • Hero Member
  • *****
  • Posts: 640
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #4 on: July 05, 2011, 12:15:54 AM »
Thanks Gyula.

I haven't added any more magnets, just additional drive coils, there are now three coils.

The drive-coils are aircore.

I'm now getting an RPM of 1305 with an input power of 0.97W, whereas with one coil i was getting  an RPM of 1400 with an input power of 6W, that's great for what i plan to do but i would love to understand it !

It's probably worth mentioning that the two additional drive coils are just like the first one, bifilar wound with a trigger wire and a power wire, but in the two new coils the trigger wires are disconnected.

Bedtime ... zzz ...

Jdo300

  • TPU-Elite
  • Hero Member
  • *******
  • Posts: 682
    • The Magnetic 90 degree rule Theory
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #5 on: July 05, 2011, 12:50:00 AM »
Hi DeepCut,

Also, your coils are going to operate most efficiently if they are matched to the input voltage you want to drive them at. In addition to the extra DC resistance and inductance, the rise time of pulses will be slower, which means the magnetic field has more time to transfer energy to the magnet to push the rotor. Additionally, if you're using a power supply that is current limited, the input voltage will drop if the instantaneous current required by the coils is too high. Having a higher inductance allows the power to be used more efficiently.

- Jason O

DeepCut

  • Hero Member
  • *****
  • Posts: 640
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #6 on: July 05, 2011, 12:52:55 AM »
Thanks for that Jason.

Couldn't resist it, found my old coil box and have added a fourth coil, current draw (untuned) is 75mA and RPM is 1402 !

Is this happening because 4 little coils are just like one big one ? Does a larger drive coil have a stronger magnetic field because of the larger number of turns even though the input power is the same ?


Thanks,

Gary.

SkyWatcher123

  • Hero Member
  • *****
  • Posts: 844
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #7 on: July 05, 2011, 01:11:59 AM »
Hi folks, i posted this at EF awhile back on my garry stanley thread.

Quote
I ran some more tests with my motor to verify Newman's principle and that which woopy and Ian discovered as well. I wired all 6 coils in series and started with 2 coils connected in series with 24 volt input, with a draw of 1amp for 24 watts @ 5 ohms total coil resistance, the motor had little torque and could not maintain much load at a particular speed. Then I wired 4 coils in series with 36 volt input, with a draw of around 700milliamps for around 24 watts @ 10 ohms total coil resistance, the motor had much greater torque and could maintain a higher load at a particular speed. Then I wired all 6 coils in series with 48 volt input, with a draw of around .5amps for around 24 watts @ 15 ohms total coil resistance, the motor again had even greater torque and could now burn my hands at a particular speed. I think this is very significant and by increasing amount of coils and magnets the motor would supply even greater and greater shaft work with the same input watts. I'd like to hear your thoughts about this.

So my observations confirm what deepcut is questioning and I do think at some point the produced or production efficiency, which is what coefficient of performance relates to, can exceed COP>1.
peace love light
tyson ;)

Magluvin

  • Hero Member
  • *****
  • Posts: 5884
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #8 on: July 05, 2011, 01:15:46 AM »
I posted this at OUR a bit earlier today   it relates...  ;]

Another excellent example is audio speakers.  Say subs.

If you have 1 sub running 100w and it gives 100db, we need to increase the power to 200w to get 103db   3db increase for each doubling of input power. 

But, if we have 2 subs, same sensitivity, and we apply 50w each, each will have 97db output, but when they are combined, we get a 6db increase!  Same power input, divided into 2 drivers, and we achieve 103db @100w   not 200w to 1 driver.   ;]

And you can do this again with 4 drivers at 25w each and you will get 106db @100w not 400w to 1 driver.

Did custom car audio fer bout 20 years. 


Mags

DeepCut

  • Hero Member
  • *****
  • Posts: 640
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #9 on: July 05, 2011, 01:32:20 AM »
@Mags, wouldn't it be great if The Secret Was In The Bass ! Music and energy :)

@Sky (and all) Yes i've just tuned it running with four coils now and am getting 1417 RPM @ 0.97 Watts :)

I have an alternator magnet-rotor at the top-end of the shaft, tomorrow my coil cores arrive, they are masonry anchor shields :

http://www.transtools.co.uk/store/prod_5326/screws-and-fixings/shield-anchors/masonry-shield-anchor-loose-bolt-m10-x-10-x-65mm-10-pack.html

I will wrap these tomorrow and see what comes out of the other end.

That's me for the night, it's half past midnight here in the UK.

DC out :)

Magluvin

  • Hero Member
  • *****
  • Posts: 5884
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #10 on: July 05, 2011, 01:45:15 AM »
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

  • Hero Member
  • *****
  • Posts: 5884
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #11 on: July 05, 2011, 01:58:22 AM »
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

  • Hero Member
  • *****
  • Posts: 640
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #12 on: July 05, 2011, 11:14:51 AM »
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.
« Last Edit: July 05, 2011, 11:43:32 AM by DeepCut »

DeepCut

  • Hero Member
  • *****
  • Posts: 640
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #13 on: July 05, 2011, 11:51:12 AM »
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

  • Hero Member
  • *****
  • Posts: 4117
Re: Why do two drive coils draw less power and create more RPM ?
« Reply #14 on: July 05, 2011, 02:16:35 PM »
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.