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2022-11-29, 07:11:28
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Author Topic: Fighters "Romanian ZPM (Zero Point Module) replication.  (Read 1677 times)
Group: Experimentalist
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PM,

i added the current probe direction on the above picture.

So what you are saying is that the lamps current flow from bottom to top?

Itsu

Itsu,

From your current probe arrows, you are correct so I'm not sure what is going on at this point!  According to Kirchhoff current law, the sum of currents leaving a junction should equal the current entering the junction.

Pm

Edit:
   
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Hi Itsu,

Would like to ask on the switching frequency here in this  current measurement test. 
 
The series bucking coils may still have the 63 mH inductance you wrote in Reply #9, right? 

So the inductive reactance may be in the kOhm range? so coils current should be in the some mA range from 12V?

The 3 bulbs in parallel may have around 10 Ohm resistance (counting back from full brightness power).

So we should have some mA coil current (at this frequency you will tell) versus the 755 mA bulb current.   12V/0.755A = 15.9 Ohm resistance for the 3 paralleled bulbs, so this bulb current seems correct for the less brightness than at full (15W) power.

EDIT:  I see your time base was set to 1 us/DIV so the frequency may have been around 333 kHz or so?   If this is correct,  then the inductive reactance of the 63 mH coil may be around 130 kOhm, so coil current is negligibly small, under a mA?   

EDIT 2: I disregarded the DC current of the coils taken from the 12V battery, sorry for that.  So the 607 mA average current should be a correct coil current, this is established in a smaller part by the series DC resistances (2.4 Ohm) and mostly depends on the ON time, i.e. the frequency (the higher the frequency the smaller the average current in the coils).

Gyula
« Last Edit: 2022-10-31, 19:02:27 by gyula »
   

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Itsu,

From your current probe arrows, you are correct so I'm not sure what is going on at this point!  According to Kirchhoff current law, the sum of currents leaving a junction should equal the current entering the junction.

Pm

Edit:



PM, 


i agree, so i also think its strange to see these currents.

Itsu
   

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Hi Itsu,

Would like to ask on the switching frequency here in this  current measurement test. 
 
The series bucking coils may still have the 63 mH inductance you wrote in Reply #9, right? 

So the inductive reactance may be in the kOhm range? so coils current should be in the some mA range from 12V?

The 3 bulbs in parallel may have around 10 Ohm resistance (counting back from full brightness power).

So we should have some mA coil current (at this frequency you will tell) versus the 755 mA bulb current.   12V/0.755A = 15.9 Ohm resistance for the 3 paralleled bulbs, so this bulb current seems correct for the less brightness than at full (15W) power.

EDIT:  I see your time base was set to 1 us/DIV so the frequency may have been around 333 kHz or so?   If this is correct,  then the inductive reactance of the 63 mH coil may be around 130 kOhm, so coil current is negligibly small, under a mA?   

EDIT 2: I disregarded the DC current of the coils taken from the 12V battery, sorry for that.  So the 607 mA average current should be a correct coil current, this is established in a smaller part by the series DC resistances (2.4 Ohm) and mostly depends on the ON time, i.e. the frequency (the higher the frequency the smaller the average current in the coils).

Gyula


Gyula,


yes, see post #22 the frequency was 330kHz.

Yes, the series opposing coils have the 63mH inductance at 10kHz.
In post #10 i have the impedance of these series opposing coils plotted (bottom graph) and around 330kHz we have an impedance of 120kOhm.

I understand from a link posted in my first post and from F6FLT in post #7 that its not really the coils making up the inductance / impedance, but rather the core material,
the wire losses and the intercapacitance of the coils.

So i still fail to see how we can have a total input current of 703mA average while having 755mA rms going through the lamps plus another 607mA going through the coils.


Itsu
   
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Itsu,

Change the measurement on CH3 to mean instead of rms.  Then I think that CH2-CH3 will equal CH4. 

Pm
   

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Itsu,

Since the bucking coils have different individual inductances, you might try reversing the leads to the coil assembly to see if the current pulse to the power supply changes polarity at the mosfet turn off.

Regards,
Pm

PM,

reversing the coil leads does not make any difference in the voltage signal nor in the current signal.

Itsu
   

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Itsu,

Change the measurement on CH3 to mean instead of rms.  Then I think that CH2-CH3 will equal CH4. 

Pm

PM, 

ok, i put CH3 (purple) in mean, but i do not think that is correct as we have an AC signal there.

As can be seen, the mean current on CH3 is about 6mA which can not be true as the 3x 12V / 5W bulbs would not light up with such low current me thinks.


Itsu
   

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Concerning the diode used on the input lead by Fighter, i tried a High Speed 12R06DI diode    https://pdf1.alldatasheet.com/datasheet-pdf/view/107509/STMICROELECTRONICS/STTH12R06DI.html

Frequency was 330kHz and the diode warmed up to 30 degree Celcius only.

But we see the impact in the screenshots, where the white trace is input current without the diode, and green input current with the diode.


Itsu
   
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PM, 

ok, i put CH3 (purple) in mean, but i do not think that is correct as we have an AC signal there.

As can be seen, the mean current on CH3 is about 6mA which can not be true as the 3x 12V / 5W bulbs would not light up with such low current me thinks.


Itsu

Itsu,

Thanks for doing that.  The mean current thru the bulbs is what the power supply "sees" and the rms is what powers the bulbs.  But things still don't match up as far as KCL is concerned!

Pm
   
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Hi Folks,

This video deals with applying KVL for a series RC circuit fed by a sinusoidal AC 60 Hz generator: https://www.youtube.com/watch?v=GZNBn06PW58 

I freezed the video at 3:56 time where the voltage across the resistor is 37.5V and the voltage across the capacitor is 33.16V but the generator feeding them has 50V only...  :D 

He explains...

   
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The title of this video is "You Can't Apply Kirchhoff's Loop Rule to a Circuit with an Inductor!"   :D

Part 1  https://www.youtube.com/watch?v=ld6d_nRTIl4    3 minute long

The title of Part 2 video is "Faraday's Law is the correct approach for a Circuit with an Inductor!

Part 2  https://www.youtube.com/watch?v=UNmEayHrCJg    7 minute long

He wrote:  "we apply Faraday's law to a circuit.  This is the correct way to think about an LR circuit, and it leads to the same result as Kirchhoff's approach."   :D

Are we better off?    C.C
   
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I freezed the video at 3:56 time where the voltage across the resistor is 37.5V and the voltage across the capacitor is 33.16V but the generator feeding them has 50V only...  :D 


I do not really get the point. The voltages at resistor and capacitor are out of phase so it is a quite a normal behavior in this circuit.
   
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I do not really get the point. The voltages at resistor and capacitor are out of phase so it is a quite a normal behavior in this circuit.


Yes, that is ok now and with reactances we need to do vector summing for voltages or currents.  So, taking the square root of the sum of (33.62 + 37.12 ) gives 50 V.

Doing this calculation with the currents in Itsu's circuit still gives a certain error though.   https://www.youtube.com/watch?v=XT4OvT0deVQ

Gyula
   

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Thanks guys, i have to digest all this.

For now, just some reminders, as that this circuit is a parallel RL circuit, not series, see basic diagram.
Also, i am showing currents, not voltages.



I also made an LTspice simulation of this circuit and put in the currents through the components as i measured them, see picture.
The lamps are replaced by resistors, frequency is 330kHz.

Green is input current, blue is coils current and red is lamps current.

It shows similar results as my present setup, but here the averages do match.

LTspice file attached




Itsu
   

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Ok, i think i spotted the problem, as can be seen in the above simulation.
The red lamp's current trace there is No AC what i initially thought it was.

Because i thought it was AC, i used my AC-only probe to measure the lamp's current, but obviously there is a DC offset on that trace which is not detected by this AC-only probe.

This DC offset is less in my circuit, so harder to spot, but still there, so now i used my AC/DC probe to measure all 3 currents (in mean) and now the input current much better matches the sum of the coils
and lamps currents, see screenshot:



The green trace is the input current (742mA),
The White R2 current is the coils current (608mA),
The white R1 current is the lamp's current (121mA).

So 608 + 121 = 729 which is close to the 742mA input current.

Sorry for the confusion.

Itsu
   

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Comparing my voltage across the lamps / coils with that from Fighters thread here: https://www.aboveunity.com/thread/romanian-zpm-zero-point-module/?order=all#comment-919e6a86-806b-493c-b8c9-aa7201308781

Fighters screenshot:



My screenshot:



We are at 327kHz, so it seems to me both screenshots are very similar.


Itsu
   
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Good job Itsu, thanks for all the hard work.

The waveforms are pretty similar to that of Fighter's, so most likely his power supply seems to cause his circuit's low input current consumption, until proven otherwise of course.

Gyula
   
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Itsu,

OK, that all makes sense now.  I also thank you for all the effort to replicate this circuit.  O0

Pm
   

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I have replaced the 12V battery now in use as DC source for a variable Power Supply like in use by Fighter, but with some additional filtering.

Without this filtering, the PS is heavily influenced (current limiter plays up, noises from inside, etc.) by the spiky signals coming from the device under test (DUT), see screenshots in posts #18 and #20.

But with some filtering (caps with CMC) things clear up, and we have an almost DC Voltage and current at the PS input:



The filtering consists of a 1uF capacitor, a 37mH CMC and a 476nF capacitor



In Fighter's thread, member Vidura also already advised the use of such a filter here:
https://www.aboveunity.com/thread/romanian-zpm-zero-point-module/?order=all#comment-19f2b67c-054e-450d-bd5e-aa750128e505
https://www.aboveunity.com/thread/romanian-zpm-zero-point-module/?order=all#comment-0f76b2a8-3a21-4499-9063-aab201244554


I will be using this filtered PS to make some further experiments.


Itsu
« Last Edit: 2022-11-07, 14:58:00 by Itsu »
   

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The above filter was measured using my nanoVNA and shows as expected a low pass characteristic.
All frequencies above a few tenths of kHz are blocked (-20 to -80dB) effectively and thus are protecting the PS, see screenshot below.

Using this filter shows we have a (parallel) resonance frequency in the device around 12kHz, which is pretty low compared to the 604kHz reported by Figther.
We see a sharp dip in input current approaching 1mA like reported by Fighter, but also my lamps go out contrary to Fighters lamps which stay on full.

I think this behavior of my device is as expected, as that in parallel resonance the impedance is at maximum and thus the current at minimum.
Strange is however that without the filter there is no resonance to be found in a 10kHz to 5mHz range, thus no dip.
So i think this filter (capacitor) is causing the device showing parallel resonance.
 
Why Fighters device also shows the input current dip, but not the lamps dimming, is still the question.


Reading further in Fighters thread, it seems there is a need for a ground connection of the device at the drain of the MOSFET which looks like a strange place for grounding to me.
Initial tests here with this ground connection does not show much difference in behavior of the device.

Will continue reading Fighter's thread and doing some measurements....


Itsu
   

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It seems that the low pass input filter has a strong influence on the workings of the Device Under Test (DUT).

The first low pass filter above caused a resonance in the DUT around 12kHz even when fed by a 12V battery, which without the low pass filter showed NO resonance in the DUT in a 0 to 5MHz range.

I now build a second low pass filter using different caps and CMC and this one causes a resonance in the same DUT (also on 12V  battery) around 308kHz.

Like the 1st one it will cause the DUT to decrease input current to practical 0mA when in 12kHz resonance, but it also causes the DUT lamps to go out.
This 2nd one does the same (decrease input current to practical 0mA) at 308kHz resonance, but also here the DUT lamps go out.

EDIT,   it turns out however that this 2nd filter does not protect the PS that much as the 1st one as the 308kHz resonance is also there on the input to the PS causing problems (current limiting etc.) in that PS.

Itsu
« Last Edit: 2022-11-08, 09:12:22 by Itsu »
   

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I still am working on a replication of this ZPM device, but I am doing it at the forum of the designer (Fighter) of this ZPM device to be found here:   www.beyondunity.org

My ZPM replication thread over there is named:  "Fighter's ZPM (Zero Point Module) replication by Itsu":

https://www.beyondunity.org/thread/fighter-s-zpm-zero-point-module-replication-by-itsu/

Regards Itsu
   
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If I understand correctly, the PS and the generator are connected to the mains and therefore share the mains earth.
In other words, the coupling to ground that loops the input circuit of the gate goes through the ground wire of the mains connection, which can have any impedance at the working frequency. For people used to HF currents, this nonsense is frightening, nothing is mastered in this setup. In particular, the capacitive coupling between the three elements of the device, the electronic circuit, the generator and the PS, can present significant impedances compared to those of the ground wires and generates current loops. The result will be anything depending on who did it and how, and even on the arrangement of the elements in relation to each other and to the electrical environment.
I suspect that the author of the setup does not understand what he is doing, since he has not provided essential data.



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