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Author Topic: Itsu's workbench / placeholder.  (Read 138172 times)

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Yes I understand that, but then the magnets are not set up the same with the toroid and the solenoid, but the effect I think is the same. What you can't have is too strong a magnet in relation to the input to the toroid. Note the solenoid coil is very flat on those others, that was for me a giveaway to what I'm thinking.

As PM says, with one cycle it will be conservative, but with more cycles, the time pumps up the output in the capacitor and gives a deceptive power output. The first pulse should be near equal, the second double, etc.

So your answer should be no, it is probably not the correct way. As MarkE showed, is, as the area is related to E even though the scope is showing voltage it is also showing pulse time (in and out are not the same duty).

It is a good topic for debate

Regards

Mike

Mike,

i also doubt that this method to measure the mag / demag field energy using the 2 diodes, 10K resistor and 22uF caps is correct, therefor my first question was about that.

But i still think that MarkE was only talking about the voltages as that was the only info (screenshot) he had.
The voltages (mean value's) can be the same, but if, as you said, the pulse time and the current are different (as they are) the energy still can be different (unequal) like i measure / calculate, and in favor of the demag phase.

Itsu

   
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...
What about the difference in energy measured in this air coil during magnetization and demagnetization?

He measured on the output coil the positive or negative voltage rectified by a diode to a capacitor with a parallel resistor. It did not measure the RMS voltage but a peak voltage which will depend on the RC time constant. This voltage cannot be used to evaluate the energy. The energy is the integration over time of the product U(t)*I(t), so it did not calculate the magnetization and demagnetization energy.

...
It almost seems like that a lot of info is not given or kept vague for some reason, perhaps to stimulate the replicator to use his brain / knowledge and find the answers he did not have, or just to keep the secret (if any) hidden.
...

The experiments seem to be well described, Naudin provides diagrams and pictures, this is positive, but there are gaps for which I don't know the reasons.
But my criticism is the lack of follow-up when he claims there is an OU. I remember him saying that he measured 10% OU on a MEG. For me it was within the uncertainty range of the measurements, but for him it was OU. So if it is OU, we must obviously persist, perfect and remove any doubt on the matter. But he has moved on! Of course he realized that there was no OU but he did not want to disavow himself. Same thing with the Kapagen: one day he measures OU, but in his following tests there is no more, and we never saw him draw conclusions on his probable error of the OU of a day that we never saw again.

I think he really believed in the emergence of this FE at that time, and now that he has abandoned the field due to his own and everyone else's failures for over 20 years.






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Thanks,

So you say that this is not the correct way to measure the mag / demag field energy of this air coil using the 2 diodes, 10K resistor and 22uF caps.

Any idea what is the correct / a better way, if any?

Itsu
   

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Thanks,

So you say that this is not the correct way to measure the mag / demag field energy of this air coil using the 2 diodes, 10K resistor and 22uF caps.

Any idea what is the correct / a better way, if any?

Itsu

It is nonsense to imagine that an air cored coil has a difference between magnetized field energy and demagnetized field energy.  But this is not an air core as it has the permeable toroidal core within its ambit.  If you measure the (open circuit, no load) voltage rise while the coil is  receiving some magnetic field from that toroid then the integral of that rise wrt time will tell you the value of the field flux within the air core.  You could then relate that to the energy that you would have got if the field came from current in the coil, and call that the magnetized energy.  You could do this by calculation or by taking the toroid away and putting in your own current to get that flux value, then doing the math to get the energy.   You could also do the integral of the voltage fall down to zero to get the value of the flux fall, and you would get the same values of flux and energy.   An air cored coil does not and can not have different mag/demag energy.

Now the coil plus that toroid is not air-cored, so could that combination have different mag/demag energies?  If so this will be a property of the toroid and that is another matter.  You wont get the answer from that nonsensical charging of the two capacitors.  The sensible thing to do there is to put a current pulse into the air core and measure the voltage rise and fall (a) with the toroid un-energized and (b) with the toroid energized.  That will tell you a lot about the effect of that toroid on the system.  You could play around with that data looking for OU.

On the subject of whether the toroid get saturated by the magnets, when using tape wound cores like metglas the core high permeability does not apply to the magnet's field being injected into the core radially, it only applied to the field along the laminations.  The field from the magnet does not follow the field lines shown in the simulations that assume the permeability is isotropic.   In fact they do not penetrate so far into the core, most of the field lines flow around the core in the laminations closest to the magnet.  And that concentration will saturate that part of the core.  This has interesting features that could apply to the MEG where flux from the input coils adds or subtracts from the magnet's flux in different halves of the core.  That adding or subtracting alters the radial depth where the saturation region occurs, so we get a form of flux-gate pumping going on.  The attached image show a simulation of the MEG core where the FEMM facility of having different values of x and y permeability is used to show the concentration of the magnet's flux in the inner laminations.

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Update from Smudge seen, much appreciated, i will digest it later.

I have measured / calculated the air coil mag / demag energy the same way Partzman (and i later-on) did on the input toroid energies here:
https://www.overunityresearch.com/index.php?topic=3691.msg98266#msg98266   Partzman
https://www.overunityresearch.com/index.php?topic=3691.msg98271#msg98271   mine.

The below screenshots show the air coil voltage (yellow) and current (green) with the load (diodes, 10K's and 22uF caps) installed.

1st screenshot shows the mag phase (in between cursors): time, mean voltage and mean current.
2nd screenshot shows the demag phase (in between cursors): time, mean voltage and mean current.

Data:

mag phase:

time 147.6us
mean voltage -5.06V
mean current 3.8mA
Energy t*V*I = 2.8uJ


demag phase:

time: 62.04us
mean voltage: 12.48V
mean current: -19.64mA
Energy: t*V*I: 15.2uJ


Several people have pointed out that the above calculations are not valid in this situation, so please ignore them.
Further down i will try to recalculate the mag / demag energy by a valid procudure.



 
So it also shows the air coil mag / demag energy difference (2.8uJ / 15.2uJ), but these are way less then the input toroid energies (457uJ / 268uJ) making
the overall COP of this device in this setup way below 1


But it seems that most votes are NOT in favor of this (2 diodes 10K and 22uF method) being the correct way to measure the (air) coil mag / demag energies.

Regards Itsu
« Last Edit: 2022-04-02, 20:52:52 by Itsu »
   
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Itsu,

IMO, taking the VA*t product to arrive at the mag and de-mag energies in each phase is not correct.  What would be correct would be to first measure the energy in the 22k resistors with Ur = Emean^2/22e-3*t .

Then calculate the energies in the 22uf caps by first calculating the voltage rise with dE = Imean*t/22e-6 and then calculate the energies with Ucap = dE^2*22e-6/2 .  Add these two energies together to arrive at the net mag and de-mag energy levels.  I'm in a rush here for a meeting but I think the ratio of de-mag to mag is >4:1.

Regards,
Pm
   

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It is nonsense to imagine that an air cored coil has a difference between magnetized field energy and demagnetized field energy.  But this is not an air core as it has the permeable toroidal core within its ambit.  If you measure the (open circuit, no load) voltage rise while the coil is  receiving some magnetic field from that toroid then the integral of that rise wrt time will tell you the value of the field flux within the air core.  You could then relate that to the energy that you would have got if the field came from current in the coil, and call that the magnetized energy.  You could do this by calculation or by taking the toroid away and putting in your own current to get that flux value, then doing the math to get the energy.   You could also do the integral of the voltage fall down to zero to get the value of the flux fall, and you would get the same values of flux and energy.   An air cored coil does not and can not have different mag/demag energy.

Now the coil plus that toroid is not air-cored, so could that combination have different mag/demag energies?  If so this will be a property of the toroid and that is another matter.  You wont get the answer from that nonsensical charging of the two capacitors.  The sensible thing to do there is to put a current pulse into the air core and measure the voltage rise and fall (a) with the toroid un-energized and (b) with the toroid energized.  That will tell you a lot about the effect of that toroid on the system.  You could play around with that data looking for OU.

On the subject of whether the toroid get saturated by the magnets, when using tape wound cores like metglas the core high permeability does not apply to the magnet's field being injected into the core radially, it only applied to the field along the laminations.  The field from the magnet does not follow the field lines shown in the simulations that assume the permeability is isotropic.   In fact they do not penetrate so far into the core, most of the field lines flow around the core in the laminations closest to the magnet.  And that concentration will saturate that part of the core.  This has interesting features that could apply to the MEG where flux from the input coils adds or subtracts from the magnet's flux in different halves of the core.  That adding or subtracting alters the radial depth where the saturation region occurs, so we get a form of flux-gate pumping going on.  The attached image show a simulation of the MEG core where the FEMM facility of having different values of x and y permeability is used to show the concentration of the magnet's flux in the inner laminations.

Smudge


Smudge,


Quote
It is nonsense to imagine that an air cored coil has a difference between magnetized field energy and demagnetized field energy.  But this is not an air core as it has the permeable toroidal core within its ambit.  If you measure the (open circuit, no load) voltage rise while the coil is  receiving some magnetic field from that toroid then the integral of that rise wrt time will tell you the value of the field flux within the air core.  You could then relate that to the energy that you would have got if the field came from current in the coil, and call that the magnetized energy.  You could do this by calculation or by taking the toroid away and putting in your own current to get that flux value, then doing the math to get the energy.   You could also do the integral of the voltage fall down to zero to get the value of the flux fall, and you would get the same values of flux and energy.   An air cored coil does not and can not have different mag/demag energy.


you say:

It is nonsense to imagine that an air cored coil has a difference between magnetized field energy and demagnetized field energy

and

An air cored coil does not and can not have different mag/demag energy.

That is good to know and i think i have to agree after reading Nikolay E. Zaev his PDF again as he there talks about "Ferrites and Ferromagnetics Free Energy Generation", so its the ferrite / ferromagnetics as core that is generating the free energy according to him.

So the output / air coil used by JN Naudin must be the vehicle to extract that energy from the ferrite.

My air coil measures 16mH @ 1KHz and this increases to 18mH @ 1KHz when the toroid coil is placed ontop, with or without the magnets attached.

I will try to follow your suggestion to measure / calculate the (even) mag. / demag. energy of the stand alone air coil to proof that it is correct what you are saying, but i am not sure i understand exactly how to do so.



Quote
Now the coil plus that toroid is not air-cored, so could that combination have different mag/demag energies?  If so this will be a property of the toroid and that is another matter.  You wont get the answer from that nonsensical charging of the two capacitors.  The sensible thing to do there is to put a current pulse into the air core and measure the voltage rise and fall (a) with the toroid un-energized and (b) with the toroid energized.  That will tell you a lot about the effect of that toroid on the system.  You could play around with that data looking for OU.


So indeed the air coil is influenced by the toroid core (inductance 16mH v 18mH) so a difference in mag. / demag. energy could be caused by that.
But you say:  "You wont get the answer from that nonsensical charging of the two capacitors.", so what do i measure with that "nonsensical charging of the two capacitors"?
I measure a clear difference in mag. / demag. energy.

Anyway, i will try to follow your suggestion and "put a current pulse into the air core and measure the voltage rise and fall (a) with the toroid un-energized and (b) with the toroid energized."


Quote
On the subject of whether the toroid get saturated by the magnets, when using tape wound cores like metglas the core high permeability does not apply to the magnet's field being injected into the core radially, it only applied to the field along the laminations.  The field from the magnet does not follow the field lines shown in the simulations that assume the permeability is isotropic.   In fact they do not penetrate so far into the core, most of the field lines flow around the core in the laminations closest to the magnet.  And that concentration will saturate that part of the core.  This has interesting features that could apply to the MEG where flux from the input coils adds or subtracts from the magnet's flux in different halves of the core.  That adding or subtracting alters the radial depth where the saturation region occurs, so we get a form of flux-gate pumping going on.  The attached image show a simulation of the MEG core where the FEMM facility of having different values of x and y permeability is used to show the concentration of the magnet's flux in the inner laminations.


Thanks for the info on metglas cores, the finemet core i have seems also tape wound, so will show similar effects as you describe.
It is strange then i think that JL Naudin shows a FEMM simulation of a Nanoperm M-059 core which seems to follow other rules with no flux leakage etc.

Thanks,   Itsu
   

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Itsu,

IMO, taking the VA*t product to arrive at the mag and de-mag energies in each phase is not correct.  What would be correct would be to first measure the energy in the 22k resistors with Ur = Emean^2/22e-3*t .

Then calculate the energies in the 22uf caps by first calculating the voltage rise with dE = Imean*t/22e-6 and then calculate the energies with Ucap = dE^2*22e-6/2 .  Add these two energies together to arrive at the net mag and de-mag energy levels.  I'm in a rush here for a meeting but I think the ratio of de-mag to mag is >4:1.

Regards,
Pm

Thanks PM,

i will try to follow your suggestion to recalculate. (you mean 10e-3 for the resistors (10K) i guess).

Itsu
   

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It is strange then i think that JL Naudin shows a FEMM simulation of a Nanoperm M-059 core which seems to follow other rules with no flux leakage etc.

It is quite clear (to me as I have done many simulations) that (a) the JLN simulation does not have a current carrying coil wound around the toroid so is not simulating the actual experiment and (b) is simulating the effect of current in the air coil that creates a field that adds/subtracts with the fields in the two halves of the toroidal core.  If you simulate the effect of current in the toroidal coil you will get flux external to the core due to saturation.  There has to be flux leakage and the experiment shows that, you can't get any voltage induction in the air coil if there is no flux leakage.

Edit.  Changed my mind about the above statement struck through.  Look out for later post.

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So you say that this is not the correct way to measure the mag / demag field energy of this air coil using the 2 diodes, 10K resistor and 22uF caps.
Any idea what is the correct / a better way, if any?
...

You have to calculate the energy by integrating the product of the instantaneous values of V and I, with the coil only feeding the resistance. I don't know if a cheap scope like Siglent or Rigol can do this directly. Apparently mine doesn't do the calculation using both channels, so if I had to do it, I would read the V(t), I(t) values on a hundred points spread over the magnetization/demagnetization time, and I would have the sigma of the products calculated by Excel.

Anyway, there is no doubt that a variable flux goes through the recovery coil since it supplies current to the LEDs. Conversely, feeding this coil will certainly make a voltage appear at the terminals of the toroidal coil, I take the bet with confidence.
If this is not proof that a flux is shared between the two coils, a coherent alternative explanation will have to be provided, along with why it would differ experimentally from the first.


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For the record, in the original "Melnichenko's Effect" thread (https://www.aboveunity.com/thread/melnichenko-s-effect/?order=all#comment-264cc704-2dba-4712-b14d-ae6a0170506a),
both Chris Sykes as Jagau expressed their feelings about some statements made here.

Especially the pertinent statement of Smudge about the zero difference in magnetic field build / collapse energy of an air coil is passionately disagreed upon.

Perhaps the misunderstanding is about the fact that Smudge specifically mentions an air coil, while Chris might talk about (and point to) a cored coil.
I think even Smudge would agree that their can be a difference in the building / collapsing of the magnetic field energy of a cored coil.


Anyway, i will avoid to start a cross-forum discussion, so will leave it this after mentioning that i indeed am not replicating Jagau his Melnichenko's Effect circuit at the moment as i am stuck right now on how his circuit looks like.
It seems a combination of Melnichenko's and the 2SGen measurement circuit, but i am lost how it is connected together and where the scope points etc. are.
When i have figured it out i might continue this replication.

Regards Itsu
« Last Edit: 2022-04-03, 16:44:06 by Itsu »
   

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I quickly knocked up a FEMM simulation of JLN's geometry but not necessarily his magnet or core data, I just used what I had immediately available.  In the images below I show the block names.  In the first two images my core has a mu of 100,000 and my magnet is NdFeB 32MGOe.  You will see that around the ring core and inside it the areas are shown as conductors, not air.  In the first image the conductors carry no current.  In the second image the conductors carry 1 amp into or out of the screen.  So that simulates the toroidal coil current.  If you compare those images with the JLN ones you will see they are identical apart from the actual flux values.  I think JLN (or whoever did the simulation) must have done this trick of making those air spaces conductors, to save him the bother of drawing more lines to put conducting regions close to the core.  Also the core mu is modeled as being linear, no saturation.

The third image has a supermalloy core which is driven into saturation.  Although there appears to be zero field outside the core, this is because the density color plot and the contour plot have cut-off values.  When I adjust the cut off values I get the fourth image that shows the leakage flux outside the core.  I adjusted values for both the contour plot and the density (color) plot so the colors in the table there give an indication of the outside values that can be compared to the values inside the core in the previous image.  They are of course much smaller which is why the experiment is such a poor transformer with COP << 1.

Smudge
   
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I've done some preliminary testing of a similar setup to Itsu's but I don't have time at the moment to post the results because my wife is in the hospital.  However, I will say that IMO the air coil is simply a flux sensor for the asymmetrical magnetization and de-magnetization of the PM biased toroid cored coil.  At least this is the case with the PM stack on the outside of the toroid as Itsu has it.  If the charge and discharge voltage levels are identical, there is little to no asymmetry in the H field.  If however, the discharge voltage level is allowed to rise far above the charge level, there is apparent asymmetry in the H field which is detected by the air coil.  I might add here that I'm using a ferrite core for the toroid and it is going into saturation during the charging phase.

The degree of asymmetry can easily be determined by measuring the areas of the positive and negative current waveforms of the air coil when shorted.  This is incorrect.  What I meant is to rectify the output of the shorted air coil with first a diode direction that indicates the magnetization of the toroid and then the opposite polarity to display the de-magnetization phase.

Regards,
Pm 
   

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I quickly knocked up a FEMM simulation of JLN's geometry but not necessarily his magnet or core data, I just used what I had immediately available.  In the images below I show the block names.  In the first two images my core has a mu of 100,000 and my magnet is NdFeB 32MGOe.  You will see that around the ring core and inside it the areas are shown as conductors, not air.  In the first image the conductors carry no current.  In the second image the conductors carry 1 amp into or out of the screen.  So that simulates the toroidal coil current.  If you compare those images with the JLN ones you will see they are identical apart from the actual flux values.  I think JLN (or whoever did the simulation) must have done this trick of making those air spaces conductors, to save him the bother of drawing more lines to put conducting regions close to the core.  Also the core mu is modeled as being linear, no saturation.

The third image has a supermalloy core which is driven into saturation.  Although there appears to be zero field outside the core, this is because the density color plot and the contour plot have cut-off values.  When I adjust the cut off values I get the fourth image that shows the leakage flux outside the core.  I adjusted values for both the contour plot and the density (color) plot so the colors in the table there give an indication of the outside values that can be compared to the values inside the core in the previous image.  They are of course much smaller which is why the experiment is such a poor transformer with COP << 1.

Smudge


Impressive Smudge, thanks for doing that.

The simulation images indeed look very much the same as the JLN images, but it takes an expert like you to point to the abnormalities or shortcuts.

So the fact that JLN says that there is no flux leakage is because of the cut off values (defaults i guess) of the FEMM program that are obscuring them.

Another thing it shows is that JLN was right when he said: "The 2SGen is not a transformer" or at least a very bad one.

But concerning the image 2, why the asymmetry (left side more flux then right side)?
The coil suppose to be evenly spread around the whole toroid, or is this a "moment in time"?

Itsu
   

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I've done some preliminary testing of a similar setup to Itsu's but I don't have time at the moment to post the results because my wife is in the hospital.  However, I will say that IMO the air coil is simply a flux sensor for the asymmetrical magnetization and de-magnetization of the PM biased toroid cored coil.  At least this is the case with the PM stack on the outside of the toroid as Itsu has it.  If the charge and discharge voltage levels are identical, there is little to no asymmetry in the H field.  If however, the discharge voltage level is allowed to rise far above the charge level, there is apparent asymmetry in the H field which is detected by the air coil.  I might add here that I'm using a ferrite core for the toroid and it is going into saturation during the charging phase.

The degree of asymmetry can easily be determined by measuring the areas of the positive and negative current waveforms of the air coil when shorted.  This is incorrect.  What I meant is to rectify the output of the shorted air coil with first a diode direction that indicates the magnetization of the toroid and then the opposite polarity to display the de-magnetization phase.

Regards,
Pm


Thanks PM,  i hope your wife is OK, don't rush things.

I am more seeing indeed that the air coil is a kind of vehicle to transfer the energies from the toroid coil, like you said a flux sensor.

Itsu
   
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  I'm following with interest.  Thanks for this research and for the reports.
   

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But concerning the image 2, why the asymmetry (left side more flux then right side)?
The coil suppose to be evenly spread around the whole toroid, or is this a "moment in time"?
FEMM can only do instantaneous moments in time.  The animated gif in JLN's site is made form a series of snap shots.  I only show one snap shot and that should agree with one frame of JLN's animation.  The magnet flux goes down the two halves of the core in the same direction (downwards) whereas the the flux from the toroidal coil goes around the ring.  Thus you get addition of fluxes in one half and subtraction of fluxes in the other half, hence the asymmetry.

Smudge
   
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In the simulation, the variable flux seems to be of the same level as the fixed flux. It seems physically impossible to me that the field created by a coil of 200 turns and a few amperes is of the same order of magnitude as that of the neodymium magnets, which represent tens to hundreds of kiloampere-turns it seems.

And if Naudin has voluntarily increased the variable flux so that it is visible compared to the fixed flux, then the simulation becomes false because a strong variable flux also modifies the permeability, thus bringing non-linearities in the signal because the permeability becomes variable in time, whereas if it is weak, only the permanent magnets drive the permeability.

While thinking about this, I remembered something that may be interesting, aside from the 2SGen. The relative permeability of neodymium is only 1.05. So if the flux from the magnet is routed through a magnetic circuit of high permeability, in which a coil creates a variable flux, then the variable flux will only be able to loop very weakly through the magnet material, its permeability being too low. So we have 2 fluxes sharing the same magnetic circuit but only the flux of the magnet will benefit from a homogeneous continuity, while the variable flux will feel the neodymium part of the circuit like an air gap. Maybe an idea to explore...


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Buy me a beer
Yes PM I hope your wife is ok, I know your concern, my thoughts are with you both

Regards

Mike


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Data:
mag phase:

time 147.6us
mean voltage -5.06V
mean current 3.8mA
Energy t*V*I = 2.8uJ


demag phase:

time: 62.04us
mean voltage: 12.48V
mean current: -19.64mA
Energy: t*V*I: 15.2uJ
That is a math error because the integral of means product is not the same as the integral of instantaneous products.
They become equal only when the voltages and currents are constant during the integration time (t).

OTOH: Estimating energy stored in a capacitor according to the formula E=½CV2 is fine when the (C) does not change with voltage or time due to dielectric soak or other weirdness of the cap's dielectric.

P.S.
The energy delivered to MOSFET's drain circuit by the gate pulse is not negligible.
   

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You have to calculate the energy by integrating the product of the instantaneous values of V and I, with the coil only feeding the resistance. I don't know if a cheap scope like Siglent or Rigol can do this directly. Apparently mine doesn't do the calculation using both channels, so if I had to do it, I would read the V(t), I(t) values on a hundred points spread over the magnetization/demagnetization time, and I would have the sigma of the products calculated by Excel.

Anyway, there is no doubt that a variable flux goes through the recovery coil since it supplies current to the LEDs. Conversely, feeding this coil will certainly make a voltage appear at the terminals of the toroidal coil, I take the bet with confidence.
If this is not proof that a flux is shared between the two coils, a coherent alternative explanation will have to be provided, along with why it would differ experimentally from the first.



F6FLT,

I have removed the air coil diodes, 22uF caps and one 10K resistor, so it now only has one 10K resistor as load, see updated diagram below.
The air coil now shows these signals (yellow voltage, green current and red calculated (V*I) power, see screenshot 1:





When i now let my scope calculate the instantaneous values of V and I of the magnetization phase only while zoomed in (between the 2 purple cursors) i get this screenshot 1:




Between those purple cursors (148.4us) we have in yellow the magnetization voltage, in green the magnetization current and in red the calculated magnetization power (V*I) as 1mW.
If we now multiply this power with the time (148.4us) we should have the energy being 0.148uJ of this magnetization phase.


Doing the same for the demagnetization phase shows the results in screenshot 3:




again, between the purple cursors (5.88us) we have the yellow demagnetization voltage, in green the demagnetization current and in red the calculated power (V*I) as 1.8W.
Multiplying this power with the time (5.88us), we should have the energy of the demagnetization phase being 10.6uJ.


So with this method we have a different outcome, but still more energy out of the demagnetization phase then for the magnetization phase.


Itsu
   

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That is a math error because the integral of means product is not the same as the integral of instantaneous products.
They become equal only when the voltages and currents are constant during the integration time (t).

OTOH: Estimating energy stored in a capacitor according to the formula E=½CV2 is fine when the (C) does not change with voltage or time due to dielectric soak or other weirdness of the cap's dielectric.

P.S.
The energy delivered to MOSFET's drain circuit by the gate pulse is not negligible.

Thanks verpies,  both Partzman and F6FLT pointed to that too, so i just tried F6FLT's suggestion to recalculate, see above post.

Partzman his suggestion (still using the  diodes, caps and resistors) i will try next if i understand what he meant  :)

Itsu
   
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What I have proposed is a way to correctly measure what Naudin wanted to measure. But is it really the magnetizing energy?
Well, no.
The magnetization energy is the energy stored by the coil and its core, while what it measures is the energy supplied to the resistor in parallel to the coil.
The toroidal coil feeds the cylindrical coil which feeds the resistor, so the energy supplied is :
W = ∫(R*I(t)² + 0.5*L*I(t)² ).dt  , also equal to ∫ (U(t)*I(t) + 0.5*L*I(t)² ).dt
As for the demagnetization energy, it is indeed ∫R*I(t)² = ∫ (U(t)*I(t) but probably more, because part of it is certainly returned to the toroidal coil. Nevertheless U(t)*I(t) gives us a default value.

So we have to recalculate the magnetization energy by adding 0.5*L*I(t)² in the sum. It is of course greater than what you have calculated.

[What I say above is without any oratorical precautions like "I believe that" or "imho" but of course I am not infallible and everyone can correct me if I say something wrong]


---------------------------
"Open your mind, but not like a trash bin"
   

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In the simulation, the variable flux seems to be of the same level as the fixed flux. It seems physically impossible to me that the field created by a coil of 200 turns and a few amperes is of the same order of magnitude as that of the neodymium magnets, which represent tens to hundreds of kiloampere-turns it seems.
I have to correct you on your misconception here.  A ring core does not suffer from the geometric demagnetization factor so the full effect of the permeability comes into place.  With 200 turns at 1 amp wound onto a core having mu = 1000 the internal field is equivalent to having that 200 turns wound on air and carrying 200 kiloamps.  That is very much into neodymium magnet territory.  So it is very easy to drive the ring core into saturation.  When you think about it there is little difference between a permeable material at saturation (all atomic dipoles aligned) and a permanent magnet material fully magnetized (all atomic dipoles aligned).  And there is not a significant difference in atomic dipole density.  So a combination of the two (like the MEG and the experiment being discussed here) could have anomalous effects.  Talking about the MEG I have some views to express but that is better put onto a dedicated MEG thread, and that I will do now.

Smudge
   

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What I have proposed is a way to correctly measure what Naudin wanted to measure. But is it really the magnetizing energy?
Well, no.
The magnetization energy is the energy stored by the coil and its core, while what it measures is the energy supplied to the resistor in parallel to the coil.
The toroidal coil feeds the cylindrical coil which feeds the resistor, so the energy supplied is :
W = ∫(R*I(t)² + 0.5*L*I(t)² ).dt  , also equal to ∫ (U(t)*I(t) + 0.5*L*I(t)² ).dt
As for the demagnetization energy, it is indeed ∫R*I(t)² = ∫ (U(t)*I(t) but probably more, because part of it is certainly returned to the toroidal coil. Nevertheless U(t)*I(t) gives us a default value.

So we have to recalculate the magnetization energy by adding 0.5*L*I(t)² in the sum. It is of course greater than what you have calculated.

[What I say above is without any oratorical precautions like "I believe that" or "imho" but of course I am not infallible and everyone can correct me if I say something wrong]



F6FLT,

thanks for your insights in these, there are always some "ifs" and "buts" attached to every little detail, that is one thing (of many) i have learned from verpies in these years.

Also now when things look obvious, there is always a layer deeper to be taken into account.

Anyway,  i am lousy with math, but when you say "adding 0.5*L*I(t)² in the sum" (magnetization), i guess you mean with "L" the inductance of the air coil (18mH), with "I" the current at magnetization (261.3uA) and with "(t)" the magnetization time (148.4us).

Putting that into your formula, i get:  (0.5 x 0.018 x 0.0002613 x 0.0001484)² which equals to 1.2e-19 which is very small.

Itsu

Itsu
   
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