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Author Topic: Charging a coil with less energy and get huge BackEMF energy pulses  (Read 24740 times)

exnihiloest

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Re: Charging a coil with less energy and get huge BackEMF energy pulses
« Reply #15 on: January 19, 2007, 04:55:39 PM »
Hi All,
I had another idea, how to get a maximum
Back EMF energy pulse from a coil.
...
So now we have a coil charged with 5000 Wattseconds magnetic
energy, which we could get back by opening the coil
and discharge it into a load via the backEMF,
but only have applied 1 MilliWattseconds of energy
to charge it up...


So where is my error ?
Can this really work, or will the coil voltage or the coil current jump somehow, when we shortout one part of the bifilar coil ?

Regards, Stefan.

Hi Stefan,

Consider the bifilar coil as a transformer. Even if you shortcut the "secondary" coil, a continuous current in the primary will cause the same continuous magnetic B field inside, because the primary doesn't "feel" the secondary due to the absence of induction current. Thus in the static case, the primary coil acts the same, the secundary to be shortcut or not. Then we will still have to put an electrical energy equivalent to 0.5*B?/mu to build up the field.

So the paradox is due to a misinterpretation of what means "L". L is the same when the secondary is shortcut but in dynamical mode it is viewed lower from the primary.
Why? From the primary we see V= L*di1/dt + M*di2/dt where M is the mutual induction factor between primary and secondary. As di2/dt is only depending on di1/dt and of reverse sign, we consider we have at the primary V= L'*di1/dt where L' = L - M.

At the primary we see a very low L' inductance permitting short time "charging", nevertheless to get the final B field which is depending only on L and not L', the energy we have to put in the primary coil is still the same: 0.5*B?/mu .

Fran?ois


gyulasun

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Re: Charging a coil with less energy and get huge BackEMF energy pulses
« Reply #16 on: January 20, 2007, 12:05:14 AM »
...
If you have no inductance when current is flowing through L1 and L2 and then you short L1, the field in the core will be non-existent and the current will rise to build up the field, I think, I may be wrong of course. Only an experiment will prove this.
Rob

Hi Rob,

I do not understand the second half of the sentence above:
1) Why would the field in the core be non-existent in that given circumstances?  I think current will still flow in L2  and  (as I wrote this already) the individual turns of L2 will create small local flux in the rod area beneath the wires.
2) Why would the current rise in that given circumstances? I think it would be insignificant/a very small rise,  for  L2 would not have a self inductance either because of the short on L1 (mutual coupling)  so there would still be no significant field build-up.

Yes, experiments would be needed.

Regards
Gyula

libra_spirit

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Re: Charging a coil with less energy and get huge BackEMF energy pulses
« Reply #17 on: March 24, 2007, 09:13:02 AM »
In a scalar cancelling coil you drive both coils opposite polarities. You can watch this with a scope while pulsing a scalar or bifilar coil. The voltage dissapears and only a very short pulse is visible going in at the start of the pulse. Now as the coils set energized with opposing magnetic field the energy moves into the torsion field compressing inwards. The coil becomes only a resistance with little to no inductance, and also no voltage setting across it.

In a scalar coil the voltage and magnetic fields dissapear, but the power supply does not seem to have a problem with this. Strange indeed.

Now the key is to release the power on one side of the coil first. As the coil goes out of balance, now from the high energy side, there is a tremendous pulse or back emf that normally fries the transisters driving them.
One way to control this back frying EM pulse is to use a mobius coil rather then a normal bifillar. Now all EM is eaten by the coil and no back EMF apears to fry the transisters.

The energy moves into the torsion field and is transmitted as a torsion or scalar wave. If the coil is placed around a copper tube, the torsion wave will move along it and can be turned back into EM using two coils connected in series and setting at 90 degrees to one another.

The torsion wave can not be detected by any EM equipment, and is often missed for this reason. It is not EM but a tempic field modulation.
Strange things happen when the magnetic field cancels in the coil, but the energy is still present, only not interactive on the EM side.

Dave L

http://magnetism.fateback.com/Theory.htmhttp://magnetism.fateback.com/Theory.htm

AhuraMazda

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  • Posts: 564
Re: Charging a coil with less energy and get huge BackEMF energy pulses
« Reply #18 on: March 24, 2007, 11:09:51 PM »
In a scalar cancelling coil you drive both coils opposite polarities. You can watch this with a scope while pulsing a scalar or bifilar coil. The voltage dissapears and only a very short pulse is visible going in at the start of the pulse. Now as the coils set energized with opposing magnetic field the energy moves into the torsion field compressing inwards. The coil becomes only a resistance with little to no inductance, and also no voltage setting across it.

In a scalar coil the voltage and magnetic fields dissapear, but the power supply does not seem to have a problem with this. Strange indeed.

Now the key is to release the power on one side of the coil first. As the coil goes out of balance, now from the high energy side, there is a tremendous pulse or back emf that normally fries the transisters driving them.
One way to control this back frying EM pulse is to use a mobius coil rather then a normal bifillar. Now all EM is eaten by the coil and no back EMF apears to fry the transisters.

The energy moves into the torsion field and is transmitted as a torsion or scalar wave. If the coil is placed around a copper tube, the torsion wave will move along it and can be turned back into EM using two coils connected in series and setting at 90 degrees to one another.

The torsion wave can not be detected by any EM equipment, and is often missed for this reason. It is not EM but a tempic field modulation.
Strange things happen when the magnetic field cancels in the coil, but the energy is still present, only not interactive on the EM side.

Dave L

http://magnetism.fateback.com/Theory.htmhttp://magnetism.fateback.com/Theory.htm

Dave
Thanks for sharing your insight. It is great to read comments from a truly learned person.
The information on your site is very enlightening and I recommend everyone visit http://magnetism.fateback.com/Theory.htm
I felt very humbled by the contents there.
Well that will keep me reading for a while.

Regards

AM