PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2024-11-26, 14:18:10
News: If you have a suggestion or need for a new board title, please PM the Admins.
Please remember to keep topics and posts of the FE or casual nature. :)

Pages: 1 2 3 4 [5] 6 7
Author Topic: Magnetic Delay Transformer  (Read 31535 times)

Group: Moderator
Hero Member
*****

Posts: 1940
Itsu,

Sounds good. O0

Smudge
   

Group: Moderator
Hero Member
*****

Posts: 1940
Just realized that the paper I posted here
https://www.overunityresearch.com/index.php?topic=3505.msg65795#msg65795
deals with the subject matter in this thread.
Smudge
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159
Finished my delay line toroid according to the "verpies" setup (see diagram) as i understand it.

Picture shows the both orange prim / sec coils (52uH each), the red and green delay line coils (each totaling 2mH)
with every 2th turn a tap to the opposite coil (each measure 6uH) with a 22pF cap inbetween.

I measured again at 100Khz, 500KHz, 1MHz, 2MHz and 2.5MHz, see screenshots.

Above 500KHz the signal flips (around 800KHz) from almost in phase to almost 180° out of phase while
the input (yellow) dips.

FG was set to 10Vpp, yellow is input signal, blue is across the 100 Ohm load on the secondary.


Screenshots for 100 and 500KHz show the delay between input output, rest was due to 180° flip somewhat
out of context so not shown, but can be measured if needed.

Itsu
   

Group: Moderator
Hero Member
*****

Posts: 1940
Wow, that is interesting!  That flip near 800KHz, does it flip suddenly, like a toggle switch with hysteresis, or is it a gradual change over a small frequency increment?  Thanks so much for doing this.  I think you will find exploring this a journey into the unknown, hopefully a journey with a satisfactory ending.
Smudge
   

Group: Moderator
Hero Member
*****

Posts: 1940
It would be interesting to know the COP for those measurements. If there is a frequency where the phase delay is 90 degrees perhaps it becomes OU since you would expect the secondary mmf as seen at the primary to appear phase inverted from normal.
Smudge
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

Hi Smudge,

i did not do much measurements yet as i wanted to be sure this is a correct setup.

The 180° flip is not that sudden, more like you said, a gradual change over a small (400KHz) frequency
increment, see short video:

https://www.youtube.com/watch?v=xDpAeWoaoa8

I will do some more measurements including some COP tests in this frequency range.


Regards Itsu
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

A quick input / output measurement from 100Khz to 5MHz shows the following data:

We see a slight Cop > 1 in the green area, so we might look into that area more in detail.

Itsu
   
Group: Guest
   Itsu:
   Well, that might be a first, and worth looking into.
   I have been following along, watching and waiting...
   My Kacher circuit also likes to run at 900KHz to 1.1Mhz.
   Good luck with your tests...
                                           NickZ
   
   
Group: Elite Experimentalist
Hero Member
*****

Posts: 901
Excellent work Itsu O0

@ 2.3Mhz looks to be the best gain!

I hope this is the real deal. You definitely deserve it  ;)

 8)Looking forward to more.

Thanks for sharing
Luc
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

Thanks guys,  but don't jump to any conclusions yet, i want to repeat these measurements a few times.

Looks like at 2.3MHz, the COP is at 1.32.


I was using my battery operated FG and used a 10 Ohm csr in the input for current measurements and
a 1 Ohm resistor as csr in the output (confirmed by using my current probe there too afterwards).

I measured EITHER the input OR the output to avoid any groundloops from my scope probes.

Doing some more tests / measurements.......   Itsu
   
Group: Guest
   Itsu:
   Might be good to try also leaving the scope's negative probe off, to see if there is any difference on the output voltage. As it may go higher...
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

Hi Nick,

i could try that but i think its a strange advice as also a scope needs to have a reference (its groundlead) to measure from like a DMM etc.

Itsu
   

Group: Moderator
Hero Member
*****

Posts: 1940
Thanks Itsu, that is most interesting.  When you get time could you repeat that COP v. frequency measurement but using shunt capacitors across the secondary (keeping the 100 ohm load)?  That could move the COP>1 region lower in frequency where core losses are less.  Start with a lowish value C (say 100pF) and see what happens.
Smudge
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159
Thanks Itsu, that is most interesting.  When you get time could you repeat that COP v. frequency measurement but using shunt capacitors across the secondary (keeping the 100 ohm load)?  That could move the COP>1 region lower in frequency where core losses are less.  Start with a lowish value C (say 100pF) and see what happens.
Smudge

I used a 100pF ceramic cap across the 100 Ohm load at the secondary and used the same setup as yesterday.
But going from 100KHz to 3.5MHz.

It seems that the frequency response is almost the same as yesterday, but the COP > 1 is gone, see
grey (input) and yellow (output) graphs below.


Will try some other shunt values......

Itsu
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

Using first a 220pF ceramic cap and then a 470pF ceramic cap across the 100 Ohm load shows that the COP gets worse and worse, see picture.

Adding the excel file too.

Itsu

   

Group: Moderator
Hero Member
*****

Posts: 1940
OK, let's leave that for now.  I guess you would like to get back to the perceived 1.32 COP (no shunt capacitance) and investigate that further.  If I were doing this I would do enough tests to convince myself that the 1.32 is genuine.  Then I would try different value load resistors, I would wave a magnet near it, I would do anything to see if that 1.32 figure could be improved.

When you get time perhaps we could get back to the original intent, to see whether the input resistance will go negative above the resonant frequency when the secondary is loaded with a capacitor (and perhaps a high value resistive load like 1M or 10M.)  Making the time delay along the core greater should have made this more likely.

Smudge
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

OK,  i will first get back to the no shunt situation and try to improve on the COP 1.32 figure.

Itsu
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159
I ran 10x the "no shunt" situation input/output test to see if i could replicate or improve on the COP 1.32 reported earlier.

Turns out that these 10 tests show a COP between 0.82 and 1.24, so i was not able to get to the 1.32 again.

I ran those 10 tests using different probes (CH1, CH2 or CH3) for voltage and current making sure to use the same set of probes for input then output.

It matters greatly where to place the probes, especially the ground leads.

When using the so called RF tip on the probe for the current measurements (so directly placed across the CSR's) the COP's > 1 were gone (COP = 0.83 range).

To show what an impact placing the groundleads have on the measurements, i finally used a very sloppy groundlead placement with the groundleads some centimeters away from its probe which resulted in a
COP of 2.9!

So once again i learned that anything above 1MHz needs to have special attention during measurements.



Going back to the original intent to see whether the input resistance will go negative above the resonant frequency when the secondary is loaded with a capacitor (and perhaps a high value resistive load like 1M or 10M.)


Regards Itsu
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

Initial tests show no negative input power (negative resistance) using a 10M resistor at the secondary
with either a 6.1nF or a 270pF cap parallel.

Same with a 270pF only (no 10M).

Using a 10 Ohm csr in the input with RF probe tips across and Rigol FG.

Problem noted is that the calculated resonance frequency using http://www.1728.org/resfreq.htm
6.1nF and 58uH = 267khz is not there, same with the 270pF cap.

Itsu
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

To visualize the noted problem about the resonance frequency, i made a sweep of the secondary voltage
using the secondary (58uH @ 100KHz) and a parallel cap (270pF).

According to the mentioned website, the resonance frequency should be at 1.27MHz

Using my Rigol FG set at 10Vpp and sweeping from 100KHz to 6MHz.

Screenshot 1 shows in blue to voltage across the secondary and in red the input power.

Resonance frequency seems to happen mainly at 3100 and 5200KHz with a smaller peak at 270KHz.

Also visible is the abcense of the dip in input power AFTER resonance.

Is this shift in resonance peaks caused by the magnetic delay lines

Anyway, zoomed in on the first small peak shows a better input dip BEFORE resonance, see screenshot 2     
 
Itsu
   

Group: Moderator
Hero Member
*****

Posts: 1940
That is good work Itsu.  Clearly the magnetic delay line makes the classical resonant frequency formula using L and C unworkable.  That dip at about 230 KHz looks interesting.  Could you try checking input and output power at that input dip frequency using smaller value load resistors to see whether you get close to COP>1?
Smudge
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159

Sweeping from 1KHz to 500KHz while displaying input power (red) and output voltage (blue).

Output is loaded with a 100 Ohm resistor in series with a 1 Ohm csr across the secondary LC (C=270pF).

Screenshot shows a broad output frequency peak around 250KHz with a dip in the input power.
So it looks like the load (101 Ohm) across the LC has flatten out the resonance peak and filled up
and moved the input dip somewhat.

Strangly when noting down the input power in 10KHz steps from 200KHz to 300KHz, it does not reflect
the shown dip, but more a steady increase, see data below.
Using the RF tip on the csr's

Frequency (KHz)    input power (mW)    output power (mW)
    200                         49.6                  42.6         
    210                         50.3                  43.8     
    220                         51.1                  44.9
    230                         51.7                  45.7
    240                         52.3                  46.4                   
    250                         52.8                  46.9
    260                         53.3                  47.2
    270                         54                    47.6
    280                         54.3                  47.6 
    290                         54.6                  47.5
    300                         54.9                  47.3

Itsu
   

Group: Moderator
Hero Member
*****

Posts: 1940
Strangly when noting down the input power in 10KHz steps from 200KHz to 300KHz, it does not reflect
the shown dip, but more a steady increase, see data below.
Hi Itsu,
OK thanks for that.  I note on your frequency sweeps the math channel shows some negative excursions, see first image below.  I presume this is an indication of some reactive watt-less power which disappears at the 250KH resonance.  Assuming that such negative excursion is a reasonable indication of reactive power sloshing back and forth, on the next image I have crudely drawn the locus of the negative excursion, then created its mirror image positive excursion.  Then the real power is indicated by how far more positive the math channel goes, as shown by the arrows.  I think this solves the apparent anomaly.

Going back to your earlier sweep without a load resistor and doing the same thing, see the third image below, it can be seen that at resonance there is little input power, but either side of resonance circuit losses show up with that "more positive" excursion.  I find it strange that resonance should almost null out those circuit losses, as you would expect the large LC circulation current to create greater loss.  So I do wonder whether at a larger value load resistor we could get nearer COP>1.
Smudge
   

Group: Elite Experimentalist
Hero Member
*****

Posts: 4159
Smudge,

thanks for explaining the strangeness i saw, that makes sense.


Redid the test with a 100K and 10K ohm resistor as secondary load (again with a 1 Ohm csr in series).

Screenshot 1 is the 10K load and screenshot 2 the 100k load (sweep 1KHz to 600KHz).

The below table shows the input / output power in both 10K and 100K load.
As there is almost no current flowing through the 1 Ohm csr, values are near to unmeasureable, so also
the output power calc's.



                                              10K load                                                100K load
Frequency (KHz)    input power (mW)    output power (mW)   input power (mW)    output power (mW)
       200                      6.3                         1.4                       5.5                          0.6
       210                      5.2                         1.5                       4.3                         0.65
       220                      4.3                         1.6                       3.4                         0.5
       230                      4                            1.7                       2.9                         0.5
       240                      3.9                         1.7                       2.8                         0.5
       250                      4.2                         1.7                       3.1                         0.45
       260                      4.8                         1.8                       3.7                         0.4 
       270                      5.6                         1.8                       4.6                         0.4
       280                      6.7                         1.7                       5.7                         0.35
       290                      8                           1.7                       7                            0.3                   
       300                      9.4                         1.7                       8.5                         0.3 


Itsu
   
   

Group: Moderator
Hero Member
*****

Posts: 1940
Thanks again Itsu.  The dip in input power clearly shows up at 240KHz, but no OU there.  IMO it is not necessary to use a CSR for the output power, just use rms voltage squared divided by the load resistor value.  A quick check taking the Pk to Pk voltage from the screen shots doesn't improve things.  I still can't explain why the circuit losses (input power minus output power) reduce at that resonance, whereas in my mind they should increase.  Have to think more on that.
Smudge
   
Pages: 1 2 3 4 [5] 6 7
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2024-11-26, 14:18:10