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Author Topic: Itsu's workbench / placeholder.  (Read 138177 times)
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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.
...

I agree, thank you, the permeability counts. So in this case as already said "a strong variable flux also modifies the permeability", and so the toroidal inductance depends on time.
If this is really the case and we inject a sine signal in the toroidal coil then the current should not be sinusoidal anymore, and we should see new frequency components appear. It is to be checked.

The toroidal core sinks partially into the cylindrical coil so the inductance of this one will also depend on time. We will assume that this variation remains negligible, otherwise the calculation will be complicated.


...
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

I don't think so. L is the inductance of the air coil, but U(t) and I(t) are the instantaneous values of each point measured by the scope. To approximate an integral, we make a sum of a calculus with discrete values taken at constant interval (which corresponds to "dt"). So we have to take the values U(t), I(t) over the time period P that we are interested in. If you can not directly provide a calculation formula to the scope, I suppose that if it is connected to a PC in ethernet or USB, the scope can provide the measurements, each at a time interval T corresponding probably to its sampling frequency (that in MS/s) or to a chosen value (I have never tried).
 
We then transfer them to Excel, with U in column A, and I in column B, we just have to add in column C the formula =A1*B1+0.5*0.636*B1^2 (0.636 is the inductance value L). This gives us the instantaneous power U*I+0.5*L*I² for the first measurement.
Then we copy the formula of column C on all the lines, each line corresponding to values measured by the scope, so we have in column C all the instantaneous powers measured.
And at the bottom of column C, if we have for example 400 measurements over the period P, we add the formula =SUM(C1:C400)*T where T is the time interval between each measurement, which gives the energy over the period P of 400 measurements (If the scope provides the measurements at a sampling rate of 5 MS/s, we will have T=1/5000000).

Without guarantee, I may have forgotten something (I count on Smudge for the corrections  ;) ). I think I'm getting tired of math... I've lost the habit.   >:(



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F6FLT,

thanks, my scope does have advanced math capabilities, but all measurements up till now point to higher demagnetization energy then magnetization energy, only the amounts differ, also probably due to subtle differences in toroid core placing on the air coil etc.

I will leave it at that for now, leaving the question if the 2 diode, resistors and caps method is the correct one to measure it open.


Itsu
   
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...but all measurements up till now point to higher demagnetization energy then magnetization energy...
I want to believe it, but if your measurements don't take into account 1/2*L*I(t)², they don't indicate the magnetization/demagnetization energy what you are looking for.


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But if i add  1/2*L*I(t)²  to the magnetization energy i get my 0.148uJ  plus your (0.5 x 0.018 x 0.0002613 x 0.0001484)² which = 1.2e-19, i still get 0.14840000....uJ

If my math is correct,  so magnetization: 0.148uJ, demagnetization: 10.6uJ


Itsu
   

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In my post #827 i had the following questions:


Quote
Questions:

# is this the correct way to measure the difference in energy going into and out off an air coil?
# if correct, is there a way to harvest this difference and get some useful work out of it?
# MarkE mentioned in the mentiond OU.com thread that the difference on the scope (voltages) are zero, so why do the voltages on the caps show different?
# in my video it shows that the "flux gating source" needs to have its magnets positioned a specific way (horizontally), for the effect to show, JL Naudin shows his magnets are vertical.
   Why is that so in my case, i mean the magnets saturate the finemet core no matter how they are positioned me thinks.


If we leave the first one open for now, and assuming we do have a difference in favor of demagnetization energy, what would be the answer for question 2:

# is there a way to harvest this difference and get some useful work out of it?

Itsu



   

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If my math is correct,  so magnetization: 0.148uJ, demagnetization: 10.6uJ
This is unusual because when an inductor is charged by a constant voltage source through a series resistance, then part of the energy is stored in the inductor and the remainder is dissipated as heat in that resistance.



The ratio of these two energies is dependent on the charging time like this:



The energy flows into the inductor most rapidly at 0.69 Tau and the rate of that flow decreases afterwards (asymptotically down to zero).



Anyway, if you can start with a charged capacitor and use the energy stored in it, to energize the inductor and later recover this energy back from the inductor into the capacitor, so that the same capacitor ends up with a higher voltage, then this would confirm your calculations.
   
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But if i add  1/2*L*I(t)²  to the magnetization energy i get my 0.148uJ  plus your (0.5 x 0.018 x 0.0002613 x 0.0001484)² which = 1.2e-19, i still get 0.14840000....uJ

If my math is correct,  so magnetization: 0.148uJ, demagnetization: 10.6uJ


Itsu
As said above but I am not very good at explaining things, your math is not correct unless I is constant.
But I is not constant.
A sum of squared values is not equal to the square of the sum. So you can't take the mean value of I for your calculation. Is that what you did or did I miss something?




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This is unusual because when an inductor is charged by a constant voltage source through a series resistance, then part of the energy is stored in the inductor and the remainder is dissipated as heat in that resistance.



The ratio of these two energies is dependent on the charging time like this:



The energy flows into the inductor most rapidly at 0.69 Tau and the rate of that flow decreases afterwards (asymptotically down to zero).


Anyway, if you can start with a charged capacitor and use the energy stored in it, to energize the inductor and later recover this energy back from the inductor into the capacitor, so that the same capacitor ends up with a higher voltage, then this would confirm your calculations.


Thanks,   but that will be hard to do as according to Smudge, in an air coil, the mag. / demag. energies must be the same.

So this anomaly (if it exists) must come from the driving toroid or the combination of driving toroid and air coil.

Measurements / calculations on the driving toroid shows its not coming from there (COP << 1), so it must (if it exists) come from the the combination toroid / air coil.

As the overall COP is also way below 1,  i doubt there will be enough energy in the starting charged cap.


Itsu
   

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As said above but I am not very good at explaining things, your math is not correct unless I is constant.
But I is not constant.
A sum of squared values is not equal to the square of the sum. So you can't take the mean value of I for your calculation. Is that what you did or did I miss something?

OK,  i see what you mean.

I used for a I its rms value during the magnetization time.

Itsu
   

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..., my scope does have advanced math capabilities, but all measurements up till now point to higher demagnetization energy then magnetization energy,
Can it do INTEGRAL(Ch1 * Ch2) or ACCUMULATE(Ch1 * Ch2) ?

If it can, then the input energy can be displayed directly. 
The only problems I can foresee is zeroing the integral at the beginning of the cycle, too high V/div settings causing vertical quantization errors ...and placing the voltage probe at the wrong side of the CSR (if CSR is used).
   

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I use the current probe, so no csr.

The advanced math capabilities are as shown here:




So yes, it can do INTEGRAL(Ch1 * Ch4)

When doing so on the magnetization phase of the air core when loaded with a 10K resistor only, i get screenshot 1:




So 152.4nWs(nJ) = 0.152uJ.      Which is very similar as the 0.147uJ i found yesterday.

Doing the same for the demagnetization phase of this air core, i get screenshot 2:




So 4.718uWs = 4.7uJ     Which is half of the 10.6uJ i found yesterday


Itsu
   

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Can't argue with these measurements.

P.S.
Indeed Ws = J.
   

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How does that Avaramenko-style output circuit behave when you connect it to a secondary winding of a ferrite transformer, while the primary current is an asymmetrical triangle wave, from e.g.: FG + TCA ?

FYI: Higher dΦ/dt induces higher voltage in an open winding, but the dΦ/dt does not influence the current induced in a shorted winding ( dB/dt does not either ).
In the absence of resistance, that current depends only* on ΔΦ. 

* I had a nasty debate about this with the late MarkE if you remember.
« Last Edit: 2022-04-04, 22:15:06 by verpies »
   

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Using a small ferrite 1:1 transformer, the FG to primary measuring the current with the current probe (green)
Yellow probe to secondary which is loaded with this 2x diode, 2x 10K resistors and 2x 22uF caps:


Itsu
   

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Using a small ferrite 1:1 transformer, the FG to primary measuring the current with the current probe (green)
Looks like that transformer's primary inductance is too small for that driving frequency.
Also, can you make that triangular waveform a little more symmetrical - like 20/80%.
   
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Verpies
Quote
The energy flows into the inductor most rapidly at 0.69 Tau and the rate of that flow decreases afterwards (asymptotically down to zero).
Anyway, if you can start with a charged capacitor and use the energy stored in it, to energize the inductor and later recover this energy back from the inductor into the capacitor, so that the same capacitor ends up with a higher voltage, then this would confirm your calculations.

This was a part of my experiments on the two capacitor paradox.

With a two capacitor source/sink setup the final energy is simply a function of the voltage on the caps following Energy=1/2CV^2. It doesn't matter what the transfer frequency, period or waveform is or the load type we always get an accurate account of the initial and final energy. It is simply the best setup to accurately measure the input versus output energy bar none.

My initial setup can be found here...https://www.overunityresearch.com/index.php?topic=3994.0

We can also determine the real time resistance/induction energy split. Following the 50% rule any resistance will always yield a 50% loss, any induction will lower the loss tending towards 100% energy transfer minus any other losses in the system such as the source/sink or component losses. Thus we can send a volume of energy through the system to determine a baseline for system losses then add an inductance or other component characteristic and determine it's real time value based on the difference above the 50% transfer rule at any given time period.

Do you understand the value of this?, were no longer measuring something as simple as a voltage drop but an energy state within the system. We can determine whether it is tending towards an energy gain or an energy loss. Not something as simplistic as voltage/current or resistance/induction within a system but the energy state.

Think of it this way, we see a FE device but it is not a device but a material system to transform energy. The only thing that matters is energy because that is the only thing which can be transformed. Energy is everywhere in everything thus it becomes a matter of energy accounting determining what is happening where and why in any given time period. If we want to understand energy then we should follow the energy not artifacts which tend to confuse the matter...

What is energy?... how, where, when and why.

Regards
AC


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Again INTEGRAL(Ch1 * Ch4) does not give the magnetisation energy, but the energy consumed in the resistor.
The magnetisation energy is INT(1/2*L*I²).

In the case of demagnetisation, this is ok because the energy that powers the resistor is the one that was stored in L so INT(1/2*L*I²) = INT(U*I) (and assuming that there is negligible interaction with the toroidal coil).

In the case of magnetisation, INT(U*I) represents energy supplied but lost in the resistance, equal to INT(R*I²), and INT(1/2*L*I²) the energy stored by the inductance which is the real magnetisation energy. So the total energy supplied during magnetisation is INT(1/2*L*I²) + INT(U*I). This is the formula to be provided to the scope.


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Again INTEGRAL(Ch1 * Ch4) does not give the magnetisation energy, but the energy consumed in the resistor.
The magnetisation energy is INT(1/2*L*I²).
Please draw a maximally simplified schematic of the energy measurement, which you are referring to, so we can discuss it (handwritten or mousewritten is fine).
   

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Do you understand the value of this?, were no longer measuring something as simple as a voltage drop but an energy state within the system.
Yes, and that energy measurement is very trustworthy when the cap's dielectric is perfect,  i.e.: no soaking or permittivity deviation with various voltages across it.
   

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Again INTEGRAL(Ch1 * Ch4) does not give the magnetisation energy, but the energy consumed in the resistor.
The magnetisation energy is INT(1/2*L*I²).

In the case of demagnetisation, this is ok because the energy that powers the resistor is the one that was stored in L so INT(1/2*L*I²) = INT(U*I) (and assuming that there is negligible interaction with the toroidal coil).

In the case of magnetisation, INT(U*I) represents energy supplied but lost in the resistance, equal to INT(R*I²), and INT(1/2*L*I²) the energy stored by the inductance which is the real magnetisation energy. So the total energy supplied during magnetisation is INT(1/2*L*I²) + INT(U*I). This is the formula to be provided to the scope.

F6FLT,

So i added INT(1/2*L*I²) to the formula (using (I*I) instead of I²), see screenshot.
The result is indeed slightly higher, 197nWs (0.197uJ) instead of the 0.152uJ found yesterday.

So still a way lower magnetization energy as the demagnetization energy.

Itsu
   

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Looks like that transformer's primary inductance is too small for that driving frequency.
Also, can you make that triangular waveform a little more symmetrical - like 20/80%.

First primary used was 58uH, now using a primary of 2.3mH (sec. = 110uH).

Input triangle is 20/80%.
Yellow secondary voltage with as load the 2x diode, 2x 10K resistors and 2x 22uF caps
green primary current

Itsu
   

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First primary used was 58uH, now using a primary of 2.3mH (sec. = 110uH).

Input triangle is 20/80%.
Yellow secondary voltage with as load the 2x diode, 2x 10K resistors and 2x 22uF caps
green primary current

Itsu
That is much nicer.  The primary current is distorted, though (not exactly triangular/sawtooth).
Did you drive the primary with FG + TCA ...or with your FG alone (which is a voltage source) ?
   

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I was wondering where TCA stands for. 

So driving it with the FG only.

   

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I was wondering where TCA stands for. 
TransConductance Amplifier (TCA or VCVS)
...and its doppelgänger:
TransImpedance Amplifier (TIA or CCVS)

At unity gain the TCA is also called "voltage-to-current converter" (V2C) and the TIA is also called "current-to-voltage converter" (C2V).
The former is the right way to analog drive an LED* and the latter is the right way to pick up an analog signal from a photodiode.

* ...and when driving an inductor with it, the current is guaranteed to have the same shape as the TCA's input - even when the inductor's core saturates. This is true within the limits of its compliance voltage - of course.
   
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Please draw a maximally simplified schematic of the energy measurement, which you are referring to, so we can discuss it (handwritten or mousewritten is fine).

Itsu has already provided the schematic in reply #870, it is simply the inductance L of the cylindrical coil connected on R4:




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