Hi Smudge
I hope it was OK to start this thread in your bench, i wanted to take a closer look at this proposed coil of yours.
I've moved my post from the partnered thread.
Quote from: Smudge on 2015.01.31, 15:31:35
Right, now listen up!! I have just done a FEMM simulation for Itsu's large ferrite rod 200 mm long by 20mm diameter. I have assumed the ferrite to be like 3F4 with a mu of 900 and a velocity of propagation of 3.88x108m/S. I have placed on this core two coils each of 100 turns of 1 mm magnet wire, that is 10 layers of 10 turns per layer. The coils are 10 mm in length and extend out 10 mm from the core surface. The gap between the cores is 60 mm so their mean separation (center to center) is 70 mm. That represents a time delay from one coil to the other of 18nS. My simulation tells me the inductance of each coil is 541uH and the mutual inductance is 183uH. Thus the coils connected in series opposing should give 715uH and FEMM confirms this when I set that up (see image). Now using that mutual inductance figure and the equation for induced negative R in my paper R=-omegaL12sin(phi) where phi is the phase delay I get the following results.
frequency omega phase Neg R
1.00E+03 6.28E+03 1.13E-04 2.61E-04
1.00E+04 6.28E+04 1.13E-03 2.61E-02
1.00E+05 6.28E+05 1.13E-02 2.61E+00
1.00E+06 6.28E+06 1.13E-01 2.61E+02
1.00E+07 6.28E+07 1.13E+00 2.09E+04
Considering the coils have a DCR of only 0.176 Ohms this suggests that we should get self oscillation at 100kHz. I can't believe it is that easy. Of course the AC resistance of the coils will be higher and I have not taken account of core losses. Also there could be reflections from the ends of the core coming into play. But the gap is not optimised, I just used 60 mm as a starting point. I think this does illustrate the potential this approach has for getting OU.
Smudge
Smudge i have 2 ferrite rods from an aerial, not sure what type of ferrite they are but their dimensions are 127mm x 9.525mm, any chance you could tell me what coils i need to wind to try your simulated setup. O0
I have 18SWG (1.219mm) & 21 SWG (0.813mm)
Cheers
Peter
Hi Peter,
I think you need coil formers that you can slide along the rod. The axial width must be small compared to the rod length, so formers that are less than 1cm wide would be good. You need a reasonable number of turns, more than 10 but probably less than 100. Put one coil at the centre of the rod and measure inductance against frequency to find the roll-off point. Then put two coils, use that roll-off frequency, energise one coil and measure the voltage from the other coil. See if you can find any phase shift of that induced voltage as you move the coils apart. If you can get a change of phase against distance you have measured the velocity of propagation which can be used to predict results. Also the value of that open circuit voltage can allow you to calculate the mutual inductance between the coils. Now you can play with the coils connected in series bucking mode. The measured inductance of that series connection allows you to calculate the coupling factor if needed. Now you are really looking for an anomalous effect that could be masked by losses, so how do we find that. One way is to add another coil so as to make a transformer, connect the bucking coils to a load and do careful input, output power measurements. Plot COP against separation distance and against frequency (lots of measurements :'() and look for a peak. If that peak goes above 1 then so much the better :)
Cyril
Quote from: Smudge on 2015.02.01, 11:27:18
You need a reasonable number of turns, more than 10 but probably less than 100.
I will add my 2 cents' worth of commentary:
Use
even number of layers to cancel any component of current that is parallel to the solenoid's axis.
The inductance increases with the square of the number o turns, the resistance increases linearly, thus more turns yield a higher L/R ratio.
Unfortunately, more turns also leads to more interwinding capacitance, that will degrade the high frequency response of the coil and cause LCR oscillations.
@Smudge
How does the interwinding capacitance vary with the wire diameter and number of turns, all other parameters being equal ?
Thanks Smudge
First i will work on the coil formers & bobbins and report back.
I will use 18 SWG, former for 8 turns per layer with 8 layers for start, so 64 turns each coil.
Thanks verpies
Even number of layers
PS if we were worried about interwinding capacitance could we not wind bifilar and connect like a tesla bifilar coil.
infact could we just use Teslas coil and slide that on the rod, it would only be 1 turn wide O0 and easily made flat on cardboard.
(http://i173.photobucket.com/albums/w75/HaggisYann/bifilar.jpg)
Cheers
Peter
Quote from: verpies on 2015.02.01, 12:35:26
I will add my 2 cents' worth of commentary:
Use even number of layers to cancel any component of current that is parallel to the solenoid's axis.
The inductance increases with the square of the number o turns, the resistance increases linearly, thus more turns yield a higher L/R ratio.
Agreed so more turns means higher Q. But this is only for a certain wire diameter in which more turns occupy more space. If you have a coil former that determines the winding area and you fill it with wire (i.e. more turns means finer wire gauge) then R also goes as the square of number of turns, and Q remains the same.
QuoteUnfortunately, more turns also leads to more interwinding capacitance, that will degrade the high frequency response of the coil and cause LCR oscillations.
That might not be a bad thing if we find that we need to operate a resonant circuit, provided that the self resonance is lower than the optimum frequency.
Quote
@Smudge
How does the interwinding capacitance vary with the wire diameter and number of turns, all other parameters being equal ?
I don't have a formula to hand but I am sure there will be one out there somewhere :-[
Smudge
Quote from: Peterae on 2015.02.01, 12:42:01
If we were worried about interwinding capacitance could we not wind bifilar and connect like a tesla bifilar coil.
infact could we just use Teslas coil and slide that on the rod, it would only be 1 turn wide O0 and easily made flat on cardboard.
Not only that but you could stack Tesla coils together to make more turns. I think you need to limit the outer diameter because the outer turns don't couple well to the core, and that will limit the turns for each flat coil. Rule of thumb, outer turns should not be more than 1 core diameter from the core surface. It would be interesting to compare your normal coils with stacked Tesla coils occupying the same volume and same turns to see if there is any difference. But that could come later.
Cyril
Sure we can try that later,they would be easier to make i think.
I have 1 coil glued and drying, 8 turns wide, 8 high and slidable, but i have to say it's really hard getting the turns side by side on the last 4 rows, the wire is really thick and hard to lay down manually.
I dropped down to my smaller wire as well, just could not do it with the 1.2mm wire.
OK 2 coil made just gluing No 2
1 Step
QuotePut one coil at the centre of the rod and measure inductance against frequency to find the roll-off point.
How am i going to do this.
I can measure inductance at 100Hz,1KHz,10KHz using my inductance meter, but not by varying a frequency linearly.
Quote from: Peterae on 2015.02.01, 16:56:36
OK 2 coil made just gluing No 2
1 StepHow am i going to do this.
I can measure inductance at 100Hz,1KHz,10KHz using my inductance meter, but not by varying a frequency linearly.
Resonate it with known capacitor values and see what frequency you get.
OK O0
Initial Test using LCR Meter with coil fitted middle of ferrite rod
Test @ 120Hz
R = 0.1055 Ohm
L = 453 uH
Z = 0.3603 Ohm
Test @ 1KHz
R = 0.111 Ohm
L = 454.3uH
Z = 2.8571 Ohm
Test @ 10KHz
R = 0.2783 Ohm
L = 453.1uH
Z = 28.474 Ohm
EDIT
I will add data below as i check different capacitors
So
100nF gives max pk-pk at about 21.27KHz 8.16V
OK switched to cap box
330nF gives 13.25KHz @7.92V before roll off
90nF gives 26KHz @ 8.16V
70nF 30KHz @ 8.16V
50nF 37.5KHz @ 8.16V
30nF 45KHz 8.24V
20nF 62KHz @ 8.208V
10nF 87KHz @ 8.32V
5nF 144KHz @ 8.32V
Calculated inductance
330nf 437uH
90nF 417uH
70nf 402uH
50nf 360uH
30nf 417uH
20nf 330uH
10nf 335uH
5nf 244uH
Well done Peter. I have put all your measurements onto a plot with a log scale to show the typical roll-off curve for inductance. The mu will have the same roll-off characteristic. So your optimum frequency will be between 10 and 20 kHz I reckon.
Smudge
I have looked at the effect of self-capacitance of the coils and find it doesn't affect the value of negative R. But it does affect the series L, increasing the impedance until you hit resonance where it is then difficult to drive current hence get any anomalous power. So verpies is right, you need to minimise self capacitance in the coils. I have amended my paper to include this, also to discuss optimum arrangements to maximise anomalous power. It is now clear that ferrite rods are not the best way to go, you need a closed magnetic circuit (of which there are plenty where OU is claimed but they haven't latched on to the delay phenomenon).
Smudge
Thanks Smudge
So whats my next move, do i abandon the ferrite rods.
I have a huge ferrite ring of unknown ferrite type, 10cm OD 6.5cm ID & 2cm high
I've just taken off a load of insulation tape so looks a bit sticky so will clean it up.
Do i need the 2 coils slideable on a toroidal core?
Quote from: Peterae on 2015.02.02, 17:28:58
Thanks Smudge
So whats my next move, do i abandon the ferrite rods.
I have a huge ferrite ring of unknown ferrite type, 10cm OD 6.5cm ID & 2cm high
I've just taken off a load of insulation tape so looks a bit sticky so will clean it up.
Do i need the 2 coils slideable on a toroidal core?
That coil looks just right so I suggest abandoning your ferrite rod. Don't bother with sliding coils, just wind some in diametrically opposite positions as per my sketch. With one coil not connected do the measurements you have just done (on the rod) on the other coil and we'll find out what ferrite it is. It might even be the 3F4 ferrite. Then go ahead and make a transformer. Perhaps you could cut down your ferrite rod to fit inside the big toroid across a diameter and use this for the primary coil. Then you could have something that will blow up your RF source >:-). Wistiti already did this with his arrangement. I think that if you have a load resistance that is too low it cannot absorb the anomalous energy so it gets fed back to the input.
Smudge
ok it's slidable a few CM either side of where it's located
dropped the turns to 32
LCR Tests
100Hz
R=0.09 Ohm
Z=2.1016 Ohm
L=3.34mH
q=23.0445
1KHz
R=0.1801 Ohm
Z=20.892 Ohm
L=3.3mH
Q=117.76
10KHz
R=0.7247 Ohm
Z=205.25 Ohm
L=3.265mH
Q=291
Quote from: Peterae on 2015.02.02, 19:28:18
ok it's slidable a few CM either side of where it's located
dropped the turns to 32
LCR Tests
100Hz
R=0.09 Ohm
Z=2.1016 Ohm
L=3.34mH
q=23.0445
1KHz
R=0.1801 Ohm
Z=20.892 Ohm
L=3.3mH
Q=117.76
10KHz
R=0.7247 Ohm
Z=205.25 Ohm
L=3.265mH
Q=291
That looks like a mu of over 2000 so it won't be 3F4. But no matter it will still be good because that high mu means a smaller propagation velocity. When you have done the capacitor bank measurements we'll find the roll-off and the optimum frequency. Then you will really be sailing O0.
Smudge
Sounds good O0
5nF 113KHz @ 14.18V
10nF 76KHz @ 14V
20nF 31.5KHz @ 14.16V
40nF 15.82KHz 14.24V
80nF 13.92KHz 13.84V
100nF 9.58KHz
330nF 4.64KHz 13.73V
I will process the data and add it here. O0
Calculated Inductance
113KHz 397uH
76KHz 439uH
31.5KHz 1.277mH
15.82KHz 2.531mH
13.92KHz 1.635mH
9.58KHz 2.761mH
4.64KHz 3.567mH
Looks like i need more data points, was in a rush tonight, hopefully get more time tomorrow night. :(
and it also looks like i have a duff reading at 13.92KHz
I just went back to try and home in again and got different results
It's really hard to find the roll off spot only a very small voltage drop at first over quiet a large span of frequency
6nf 88KHz
7nF 57KHz
8nF 46KHz
9nf 39KHz
10nF 48KHz
11nf 41KHz
12nF 50.4KHz
Not sure why 12nF is so different maybe one of my caps is way off in the box, they are high voltage caps 1500V so maybe +/- 20%
I've run out of time to try and work out whats going on right now, Smudge see if you can make sense of any of the data, if not i will try again tomorrow, it's only 2 degrees right now in my shed and earlier it was toasty warm 16 deg C maybe that's changing something.
Maybe a better way is to measure the capcaitance instead of relying on the printed value.
Quote from: EMdevices on 2015.02.03, 03:07:16
I don't want to discourage any experimentations, but I looked at the paper smuge posted, about the negative resistance, and I would say it's a bit more complex than that, since coils have inter winding capacitance, resistance, etc.
However, the math deriving the negative resistance does look right assuming a phase "delay" in the mutual coupling of ideal inductors. But that's the big IF, is there really a phase shift? Yes there is always propagation delay, between objects spaced apart, since energy travels with the speed of light, but does that produce extra energy? No I don't believe so.
So what's the problem?
Well it appears at face value to be a case of mixing apples with oranges, i.e. Mixing time domain analysis with sinusoidal steady state analysis. Talking about a phase shift implies steady state, meaning the transients have died down, and we're exciting the circuit with a pure sinusoidal signal.
EM
Hi EM,
Sine waves are not steady state and you can handle sine waves in either the frequency domain or the time domain. For a time delay of t the phase delay is omega*t. So I don't understand where you are coming from. And there is evidence of the time or phase delay along a core, it has been measured. And it is considerably less than c. I have no doubt that Peter will measure it on his big toroid when he gets that far.
Smudge
Quote from: Peterae on 2015.02.02, 20:42:58
I've run out of time to try and work out whats going on right now, Smudge see if you can make sense of any of the data, if not i will try again tomorrow, it's only 2 degrees right now in my shed and earlier it was toasty warm 16 deg C maybe that's changing something.
Maybe a better way is to measure the capcaitance instead of relying on the printed value.
Those measurements are enough to find the roll-off characteristic, see chart. The fitted curve shows the typical roll off expected, and it is obvious this is not a HF ferrite. So you need to experiment in the frequency range between say 3 and 10KHz. Perhaps settle on 10KHz for easy inductance measurements.
I would wind an identical coil on the other side of the toroid then do some some measurements. Of most importance is the time or phase delay so I would apply a sine wave voltage to one coil and measure the voltage on the other coil, then attempt to establish the phase between the two voltages, e.g by timing between the zero cross overs. Unfortunately the delay could be less then 0.2 degrees so might not be measurable. Then I would establish the mutual coupling between coils by measuring the current in the input coil (1) and the voltage from the output coil (2). The mutual inductance L
12 is dPhi
2/di
1 which for linear materials becomes Phi
2/i
1. Phi
2 can be got from Ph1
2=V
2/(omega*N) where N is the number of turns. Next I would connect the coils in series bucking and measure the inductance of that series combination. You will know whether they are bucking because if they are not the inductance will be 4 times that of a single coil, whereas in bucking mode the inductance will be less than that of a single coil.
Then I would wind a few turns of primary coils over the secondary coils, connect them in series bucking, put a load across the secondary and see what happens when you apply an input. Should work as a transformer but hopefully an OU transformer.
Cyril
Quote from: EMdevices on 2015.02.03, 03:07:16
I don't want to discourage any experimentations, but I looked at the paper smuge posted, about the negative resistance, and I would say it's a bit more complex than that, since coils have inter winding capacitance, resistance, etc.
He accounted for the inter-winding capacitance in the
new version (http://www.overunityresearch.com/index.php?action=dlattach;topic=2773.0;attach=16424) of his paper.
I just want to point out that my formula for the induced negative resistance R=-2*omega*L12*sin(phi) where phi is a small phase angle can use the small angle approximation sin(phi)=phi (with phi in radians of course). Then since phi=omega *tD where tD is the time delay for magnetic propagation between the coils you end up with R=-2*omega2*tD*L12. Note the omega2. Even small time delays can be significant.
Smudge
edited to add the missing 2 factor
Can you contrast the electromagnetic propagation delay in a coaxial cable vs. the magnetic propagation delay in a magnetic circuit and contrast the differences in their energy transfer characteristics?
Quote from: verpies on 2015.02.03, 14:06:52
Can you contrast the electromagnetic propagation delay in a coaxial cable vs. the magnetic propagation delay in a magnetic circuit and contrast the differences in their energy transfer characteristics?
The velocity of propagation in a coaxial cable is determined by the dielectric and is given by v
p=c/sqrt(e
0*K) where e
0 is free space permittivity and K the dielectric constant. And evidence point towards the propagation along a magnetic rod being v
p=c/sqrt(mu
0*mu
R). So in that respect they are similar. However with regard to attenuation one should really compare a magnetic rod with a dielectric waveguide where electric or magnetic flux leakage occurs, but note leakage by itself is not necessarily a loss in energy transfer, it's only a redistribution of energy stored (transformers can work quite well with flux leakage present, it merely appears as a loss-less inductor in the equivalent circuit). As regards energy loss when energy is transferred from coil to coil we have to take account of the known core losses just as we would in a normal transformer. I have tried to do this by using the real and imaginary parts of the permeability tensor, and this loss only becomes significant when you get near the cut-off frequency. But I cannot relate it to an equivalent coaxial cable. In one of my papers I do give a lumped constant version of the magnetic delay line where the components are all magnetic domain ones, and show how you can use the permeability tensor to obtain values for those components. That allows you to use classical transmission line theory to solve that network, but you have to be aware that the magnetic values do not have the same meaning as electric ones. For instant mmf is magnetic "voltage" but it doesn't have the dimension of voltage, its actual dimension is current. Magnetic flux is magnetic "current" but its dimension is Webers. Thus the magnetic "attenuation constant" in that delay line does not have the dimensions of power attenuation, we merely use electric analogue to solve the magnetic equations. As I see it loss ocurs in the magnetic core material and loss occurs by EM radiation. At the frequencies we would use I think we can discount radiation losses, but I could be wrong there. In order to match real measurements to the theory in a magnetic delay transformer I had to include some radiation loss, but when practical steps were taken to screen off any radiation it didn't do any good. So the jury is out. What I like about this bucking coil theory is that it does not predict a small effect, but we will have to wait and see on that one.
Smudge
This may be partially relevant:
https://www.youtube.com/watch?v=AP0aTogfmxU
Notice how the coils are assembled where intermediate test points can be examined. Clearly you can see the increasing phase shift as he moves further down the coil.
My feeling is the coil itself IS the transmission line here. I would have to think the electrical delay is also happening with the magnetic flux, mostly inside the tube.
That looks like a large ferrite cylinder being used as a core. Putting coils on a common ferrite rod is one way of making a delay line. What it does demonstrate is that we have ways and means to increase the delay between our coils if we need to, since those voltage waveforms indicate the flux so there is a magnetic propagation delay along the rod (or cylinder in this case). But one thing at a time.
Smudge
Shall, i wind 1 coil Anti Clockwise and the other Clockwise, or both the same direction and use the connections to buck them.?
Not too much time tonight, we will see how it goes.
Quote from: EMdevices on 2015.02.03, 16:24:53
Here's a simpler circuit to implement time delay, a coax cable connecting 2 pulse transformers.
i think the whole point Smudge's comparison between EM transmission lines and magnetic delay lines, is that they re not equivalent energetically and unit wise.
Quote from: Peterae on 2015.02.03, 17:34:39
Shall, i wind 1 coil Anti Clockwise and the other Clockwise, or both the same direction and use the connections to buck them.?
Not too much time tonight, we will see how it goes.
I don't think it matters which way you do it but Chris seems to think it does. Whatever you do make a note of it so that it can be looked into as a change later on.
Cyril
Hi all,
Let me introduce myself briefly. I've worked with Smudge on several projects in the past, and was happy to run across him doing research on bucking coils somewhat similar to what we have been doing. I've read this new thread but not all of the 'partnered coils' thread that came before, so forgive me if I repeat something that has already been covered.
Something similar was done by Greg Watson in 1997:
http://www.nanoworld.org.ru/data/01/data/club/overuni/pmod.htm
where he claims a self-powering PMOD unit generating 78 mW. He says:
PMOD. If we have a coil and ferrite core, it is possible to time separate the current applied to the coil by an external Emf source and the resultant back Emf generated as the ferrites domains align. I have found that there is a time delay of approx 20-30ns from the application of the coils H field and the domains starting to rotate into alignment and producing a back Emf. If the coil is driven for only 20-30ns, only a small amount of self induced back Emf is generated (the coil acts like the ferrite is not there). After the 20-30ns wide drive pulse, the coils H field is gone but the domains are still moving (they have inertia) and will generate quite a large back Emf which can be tapped.
He used an old radio antenna ferrite about 150 mm long. He appears to have used the 3C80 material, with a LF mu of around 4000.
He has some interesting tips.
Even before that a lot of this research was done in the study of 'bubble memories'.
Orthofield
Quote from: EMdevices on 2015.02.03, 16:24:53
Here's a simpler circuit to implement time delay, a coax cable connecting 2 pulse transformers.
Think of the primary coils of the transformers as the coils of interest. The secondaries just transduce the flux change to voltage and back at the other end of the transmission line with time delay.
So bend the coax and bring the transformers close together so that you can wire up the primaries in series. This should be an equivalent circuit to test the effect of time delay in flux. But remember, don't blame me if you don't get free energy.
I think there is something special about magnetic propagation through a ferromagnetic medium that you won't get with delay through coax. Even if the coax has a dielectric the E field moving along that dielectric is transverse. In magnetic cores the mag field is longitudinal. And there is something special about longitudinal waves or near-field waves. I have yet to see evidence that core loss due to magnetic viscosity actually all goes as heat, it is just assumed that it does. The math says that the delay can both cause a loss (coils aiding) or a gain (coils opposing). Where does the energy go to or come from in those two cases? In both cases you can construct an elliptic flux v current loop where the deviation from a straight line is due to the phase shift caused by that delay. In one case the loop it traversed CCW (loss) and in the other CW (gain). If the loss goes as heat, the gain must come from cooling. It will be interesting to find out.
Smudge
Welcome orthofield
Sounds good chaps
I am also working on my digital monostable with fet driver output, this maybe capable of a 4-6 amp pulse with a very short width, not yet sure how small but i have certainly done 17nS but with a fet attached it ended up much wider at about 100nS.
I tested that by setting the pulse width to 17nS and i would get a pulse from the fet with that low setting, things should be much better with just the fet driver.
I use a MCP1406/1407 driver chip
http://ww1.microchip.com/downloads/en/DeviceDoc/22019B.pdf
OK Wound second coil inductance was a bit higher at 3.6mH not sure why, i could try taking 1 turn off and see if that balances it.
Anyway no chance of seeing a phase difference at 10KHz
I have 2 scope shots
1st is across both coils, green sig gen coil, yellow second coil ww2
2nd is with a 19.958 Ohm measured non inductive resistance in series with the sig gen and green trace.
yellow across second coil.
Hi Smudge,
I agree that there is something special about the domain delay vs. transmission line delay. You can think of of a wave of rotating domains in a ferrite rod (for instance) as a transfer of mechanical energy down the rod. The changing domains generate energy when they pass through the distant coil, and in turn this coil can reflect back to the first with a second wave of domains. In a transmission line any energy that is reflected from the far end of the line is subtracted from the load at that end, but this doesn't seem to be the case with the magnetic domains. The very act of tapping off the energy at the far end should causes the domain wave back to the start.
I do think the domain movement losses should show up as heat, and are equivalent to hysteresis losses, but there are cases where the domain movement is not lossy. Bubble domains in the old memories could be created and destroyed, but didn't lose mechanical energy in progress.
It's possible that electric delays in a Tesla/Avramenko one wire system could be used similarly to magnetic lines.
Peterae, nice work, not a snap getting sharp 17 nS pulses. This is comparable to what Greg Watson was using and should see results. Note Greg's use of a very thin gap to 'reset' the core for another pulse. If the core is continually subjected to pulses in the same direction, it will tend to magnetize and the effect will be lost over some cycles. Ideally you want back and forth motion of the domains, like in the Sweet VTA.
What happened to Greg Watson, anyway?
Hi EM
Yes i had seen this but seen as it's the current flowing in the Inductor i thought it would be 90 Degrees.
Peter
Quote from: Peterae on 2015.02.04, 19:32:37
Hi EM
Yes i had seen this but seen as it's the current flowing in the Inductor i thought it would be 90 Degrees.
Peter
I think EM missed the fact that you measured the voltage across the resistor, he assumed it was across inductor and resistor in series.
Not surprised you didn't measure any phase shift, it calculates out at a fraction of a degree. But nevertheless it must be there and it will induce a small negative resistance for the bucking mode. So worth going further methinks. But to answer Chet's question in another thread, moving to a higher frequency ferrite where you could work at say 10MHz instead of 10 KHz should give a 10^6 improvement in negative resistor value, so well worth purchasing those toroidal cores.
Smudge
>What happened to Greg Watson, anyway?
It's not a pretty picture, verpies. He was involved in a seeming solar power scam in 2008:
http://revolution-green.com/sun-cube-sad-story-solar-going-wrong/
When I worked with him he seemed to be a sincere researcher, if a bit self aggrandizing-- not an unusual feature :-)
orthofield
OK 2 main coil 32Turns each bucking config
100Hz
L 360uH
Q 1.475
R 0.1534 Ohm
Z 0.2736 Ohm
1KHz
L 360.4uH
Q 14.592
R 0.1551 Ohm
Z 2.2701 Ohm
10KHz
L 360.2uH
Q 98.07
R 0.2301 ohm
Z 22.637 Ohm
now to wind a primary on top, 5 turns each bucking mode.
OK 5 turns each measuring 89uH
Bucking @ 10KHz gives
L 9.729uH
R 0.0417 Ohm
Z 0.6127
Q 14.664 Ohm
that's all for tonight though :-\
So next then i need power measurements
If i place 1 20 Ohm non inductive resistance in series with the primary bucking coils and driven by the sig gen and then use a second 20 Ohm as my load across the bucking 32Turn coils.
I don't have the joy of a current probe.
How do i setup for power measurements.
Hi Peterae,
I just would like to make sure I understand your findings so far. I apologize if I'm going over old ground here...
First you tested the reduced reactance effect with bucking coils. Bucking series L1 and L2 have a much lower net L than they would separately. As befits a ferrite core, the L values of the bucking config are pretty stable between 100 Hz and 10 Khz.
Since there is a 90 degree V phase shift, as EMdevices said-- this must be a phase shift already, right?... as a transformer the voltage should be the same phase or 180 away.
The addition of the bucking coil is similar to tests that partzman and I have been doing. I'll let him explain these in more detail when he wants. For myself, I've been collecting information that a delta/T or star connected set of three mutually inducting coils can have a negative resistance in one coil leg in steady state AC operation. If the leg with the negative resistance contains a resistive energy generator, then the internal resistance of this generator can be cancelled.
The main reference to this is Tellegen's patent US2093665, "Star And Delta Connection Of Impedances" where he shows that the basic math of transforming a star into a delta indicates a net -R, or -L on one leg, as the result of a positive impedance on another leg. He describes a variety of interesting circuits in this totally forgotten patent, but the first couple paragraphs will suffice. Bode later claimed that in filters based on Bartlett's theorem, the actual resistance of the leg carrying the pass frequency would be nulled out by this -R in his T section filters. There are other examples of this.
I know this seems to get off subject, but it seems as soon as you start putting a third coil on the bucking coils, then you may have some of these -R effects even in steady operation, and this would be an entirely separate effect from the domain-based phase shift. This use of a third coil is more like what partzman and I have been doing lately.
orthofield
Hi orthofield
Interesting patent, need a bit more time to look it over.
Post 1 explains that Smudge was able to simulate a negative resistance.
http://www.overunityresearch.com/index.php?topic=2773.msg45196#msg45196
We switched to toroidal ferrite as it calculates out a stronger effect.
More description in Post 20
http://www.overunityresearch.com/index.php?topic=2773.msg45368#msg45368
I've not really tested that much so far, just been winding turns and testing these, the bucking tests will start tonight hopefully.
Just to be clear when i post data like below then this is just my LCR meter measuring a coil at 100Hz, i can measure at 1KHz & 10KHz Also.
100Hz
L 360uH
Q 1.475
R 0.1534 Ohm
Z 0.2736 Ohm
Thanks
Peter
Quote from: Peterae on 2015.02.04, 20:46:46
OK 2 main coil 32Turns each bucking config
100Hz
L 360uH
Q 1.475
R 0.1534 Ohm
Z 0.2736 Ohm
1KHz
L 360.4uH
Q 14.592
R 0.1551 Ohm
Z 2.2701 Ohm
10KHz
L 360.2uH
Q 98.07
R 0.2301 ohm
Z 22.637 Ohm
now to wind a primary on top, 5 turns each bucking mode.
OK 5 turns each measuring 89uH
Bucking @ 10KHz gives
L 9.729uH
R 0.0417 Ohm
Z 0.6127
Q 14.664 Ohm
that's all for tonight though :-\
So next then i need power measurements
If i place 1 20 Ohm non inductive resistance in series with the primary bucking coils and driven by the sig gen and then use a second 20 Ohm as my load across the bucking 32Turn coils.
I don't have the joy of a current probe.
How do i setup for power measurements.
OK as expected in bucking arrangement the inductance is very much smaller than that of an individual coil indicating almost complete cancellation. So in the formula L=L
1+L
2-2L
12 the mutual coupling term L
12 is almost equal to L
1 or L
2. Let's say 3mH for L
12. From your single coil inductance I calculate the core mu to be over 2000, let's say 2000. Using a ferrite dielectric constant of 6.7 (could be more) and v
p=c/sqrt(mu*K) I get the velocity as 2.6x10
6. With a separation between coils of 0.135m the time delay is 52nS. At a frequency of 10KHz that is a phase shift phi of 3.3millirads. Hence sin(phi)=3.3x10
-3. The negative resistance formula R=-2*omega)L
12sin(phi) yields a value of minus 0.062 ohms. That can be compared with your measurement of 0.231 ohms positive. So if you shorted your coils so that the power all got dissipated in their resistance and used the heat as an output you would have a COP>1. For a given current flow i the heat power would be i
2*0.231 while the input supplied input power would be i
2*(0.231-0.062), hence COP=1.37. But using a large value of load resistor you would reduce the COP so not worth doing. For maximum COP the load resistor should equal the negative one then COP is infinite. I think you can now see why going higher in frequency is desirable. All else being equal if you could operate at 100KHz the negative R would be 6.2 ohms, at 1MHz it would be 620 ohms, at 10Mhz it would be 62 Kohms.
Smudge
Smudge
Working on getting what we need for higher frequencies
Chet
Quote from: Chet K on 2015.02.05, 10:03:43
Working on getting what we need for higher frequencies
I am afraid that even with a HF toroid we will soon run into the problem of not having an analog amplifier at these frequencies.
A weak unamplified signal will be drowned out by the noise.
A digital amplifier (for rect waves) can be made pretty easily but an analog one (e.g. for sine waves) is a difficult beast. I have one up to 200MHz @100W and it weighs 25kg (55lbs).
Dear All.
Is there a realativly simple method to determine the AL value of a Ferrite? Please be aware that I have not got anywhere near the test equipment that Peterae has got.
Cheers Grum.
If you have an inductance meter then just divide the inductance by the number of turns squared.
If you don't then drive the inductor (like Itsu) from a signal generator, UCC driver and a MOSFET with a low duty rectangular wave and measure how quickly the current rises with a scope and a CSR.
Hi Peterae,
Thanks for the breakdown.
>Interesting patent, need a bit more time to look it over.
The take away is that if three coils are centered tied, then in some cases a form of negative resistance will ensue even in the static AC condition. This type of -R can "only" reduce losses, but is easily confused with a power gain, which is a -R that is greater than the real R of the circuit.
I agree with Cyril that a power gain can result from the time delay in bucking coils, although I come at it from another standpoint. Although greatly interested in negative resistance, I thought in terms of creating a pulse so short relative to the length of the core that it becomes a distinguishable domain wall moving through the core (which I imagined as a long ferrite stick).
Then, the pulse is over by the time the moving domains reach the further coil, so no loading results. It takes little energy for the source to create the moving domain wall, and not only does it power the load at the far end, but the load reaction itself creates another domain wall moving back to the start. In this case, the source must become a sink after the initial pulse. Smudge may be referencing this possibility when he talks about the coils being suddenly connected to a low impedance.
The situation is made more complicated by using two bucking coils. Then the timing must be such that the return pulse doesn't overlap the source pulse. It almost seems as if the Bloch walls would pass through each other as solitons.
Although Smudge has suggested the effect can exist in continuous AC, I think a very short pulse is much more likely to get good results, initiated at one end of a decently long high mu ferrite rod, and measured at the other end.
A few notes interspersed below:
Post 1 explains that Smudge was able to simulate a negative resistance.
http://www.overunityresearch.com/index.php?topic=2773.msg45196#msg45196
We switched to toroidal ferrite as it calculates out a stronger effect.
--It's just a hunch that a ferrite rod will work better. Perhaps because the ends of the rod represent 100% reflection.
More description in Post 20
http://www.overunityresearch.com/index.php?topic=2773.msg45368#msg45368
I've not really tested that much so far, just been winding turns and testing these, the bucking tests will start tonight hopefully.
--OK, that's what I thought. When you started talking about a third coil, I thought I must have missed something.
Just to be clear when i post data like below then this is just my LCR meter measuring a coil at 100Hz, i can measure at 1KHz & 10KHz Also.
--Sure. Have to start with that.
orthofield
100Hz
L 360uH
Q 1.475
R 0.1534 Ohm
Z 0.2736 Ohm
Thanks
Peter
[/quote]
Hi Cyril,
On looking at a ferrite catalog, Peterae's test is probably being done with something like Fair-rite material 78 which has an initial mu of 2300 and a roll off at 1 Mhz:
http://www.fair-rite.com/newfair/materials78.htm
I assume that we want the initial mu to be as high as possible, since a higher mu will represent both a longer delay, and less loss. Unfortunately the HF ferrite materials have mus around 40-150. Do you think these tests will work with the typical low-mu HF pulse transformer materials? How important is having the mu high?
orthofield
Fair enough so we want a large toroid using 3F4 ferroxcube material.
Equivalent to 3F4 are the following
Material 75G
Epcos N92
MMG F49
TDK PC50
FDK 7H10
Magnetics K
Nicera BM29
TDK have discontinued PC50 in favour of a newer PC95 material
http://www.mhw-intl.com/news/2009/10/tdk-power-ferrite-pc95-verses-pc50/
PC95 is electrically conductive at 6 Ohm per metre and is mn-zn ferrite
I've tried tracking down 3F4 made by other manufacturers and so far not found any big toroid's that are the same material, infact it's beginning to appear this type of ferrite is being discontinued.
Hi Peterae,
The 3F4 has an initial mu of around 900. I wonder if this will cause a higher attenuation, or if it really matters? I guess we will see...
orthofield
Quote from: orthofield on 2015.02.05, 17:38:46
Hi Cyril,
On looking at a ferrite catalog, Peterae's test is probably being done with something like Fair-rite material 78 which has an initial mu of 2300 and a roll off at 1 Mhz:
http://www.fair-rite.com/newfair/materials78.htm
I assume that we want the initial mu to be as high as possible, since a higher mu will represent both a longer delay, and less loss. Unfortunately the HF ferrite materials have mus around 40-150. Do you think these tests will work with the typical low-mu HF pulse transformer materials? How important is having the mu high?
orthofield
Higher frequency has a larger effect than higher mu since the induced neg R goes with omega^2 while the sin(phi) goes with sqrt(mu). Peter has just sent me some Farnell data on large toroidal cores and it looks like 3C90 material will do the job.
Smudge
OK ordered 1 of these
http://uk.farnell.com/ferroxcube/t102-66-25-3c90/ferrite-core-toroid-3c90/dp/2103392
and some 1 Ohm thick film resistors for the load.
Dam if i ordered 1 hour earlier then they would have been here tomorrow.
Hi Smudge,
Thanks for answering my question.
I remember you saying at one point that the higher the mu, the longer the delay, which makes sense from a magnetic energy storage standpoint.
I did some looking in my book on bubble memories, and found that the velocity of a domain wall in a bulk sample is based on the Landau-Lifshitz-Gilbert equation for the amount of torque the domains of a particular material see with a given magnetization H. The actual equation for a particular material is:
V = Y/a * Lw/pi * deltaH
Where Y is the gyromagnetic ratio of the material involved, a is a damping factor, Lw is the width of the wall, and of course delta H is the impulse field applied. The damping factor is much smaller for films than for bulk materials which is why bubble memories use films.
You can see from this that for a given core with its material and width that the rate of change of the applied magnetic field is the major determiner of how fast the wall gets moving, and thus how short the delay between source and load coils is. Oddly to me, a lower amplitude H field in the source leads to a longer delay since the domain wall is moving at a slower rate
There doesn't seem to be any dependence on mu at all, and the subject is not mentioned in the book. Maybe this is because the energy in the domain wall is really mechanical-- a moving torque so to speak, rather than actually magnetic.
orthocoil
Hi Smudge, all,
Correction, the velocity of the domain wall is based on the absolute value of H, not on delta H.
orthocoil
Quote from: Peterae on 2015.02.05, 20:58:15
http://uk.farnell.com/ferroxcube/t102-66-25-3c90/ferrite-core-toroid-3c90/dp/2103392
Wouldn't the Ferroxcube T140/106/25-3E25 be better for this purpose?
verpies the price is large at £95.87 and 3 times the price of the one we bought, but if we can prove the concept works then it could be bought.
Quote from: orthofield on 2015.02.05, 22:15:52
Hi Smudge, all,
Correction, the velocity of the domain wall is based on the absolute value of H, not on delta H.
orthocoil
The reason I treat ferrite like a magnetic dielectric with the velocity related to permeability and permittivity is (a) work done on 3F4 material that indicates this could be so and (b) claims of delays in the tens of nanoseconds that also fit that assumption. There may be much slower effects for domain wall movement that could on the one hand improve matters but on the other hand since energy is involved it could make matters worse. Hence the need for experiments.
It may be that the previous measured effects are not due to mu or even domain wall movement at all, maybe the dielectric constant of ferrite is much greater than the figure of about 7 that I use. My trusty Reference Data for Radio Engineers says that dielectric constants as high as 100,000 have been measured on several ferrites having a small amount if divalent iron in their composition. So maybe the EM propagation previously seen is due to that, and it represents a weak transmission running ahead of the slow domain wall one. All I can say at the moment is a large 3F4 toroidal core in a magnetic delay transformer exhibited anomalous effects at 14MHz, and the use of bucking coils would considerably amplify that effect and make it appear at a lower frequency.
Smudge
Hi Mudge,
OK, now I see your reasoning a bit better... Is the 3F4 study on the 'partnered coils' list somewhere?
The guy who did extensive study of the dielectric constant of various ferrites was J. L Snoek, but his book came out in 1947. There is also a paper in my files somewhere on 'anomalous dispersion in ferrites'. I'll do some looking and see if there is more hard data on 'ferridielectric dispersion'. I found a paper on e in NiZn right away-- around 40 and starts dropping off at a maximum of 40 Khz or so. Fig. 4 on pg. 5 shows the inverse relation of resistivity to e for these ferrites.
On the other hand the Brockman patent attached shows that Snoek measured e of MnZn in the 10-4 to 10-5 range, resulting in high core losses:
"In view of the large permeability and the large dielectric constant the wave length of the electromagnetic wave generated in the core becomes of the same order of magnitude as the dimensions of the core in its usual form and thereby standing waves are established in the core".
I'm not sure exactly what was seen in the toroid, but this standing wave could certainly cause an interesting situation. Although he is representing this as a loss, the standing wave is actually adiabatic and transmits energy quite well, although of course energy is extracted from the source so not OU in itself.
If indeed the effect you are seeing is due to a magnetoelectric wave through the ferrite, then the geometry, the size, and the bulk mu and permittivity would factor into the resonances, so only experiment will show what they are in any particular case, without some wave mechanical simming inside a ferrite-- ouch.
The domain wall movement could also also be very fast with short pulses with a high rise time, so there is the possibility of the combination of domain wall and magnetoelectric effects.
There is a wealth of literature about this subject, so maybe I should send to your email rather than to the group at large.. does everyone want to get the full ream of papers and patents I can potentially send ? :-)
orthofield
The reason I treat ferrite like a magnetic dielectric with the velocity related to permeability and permittivity is (a) work done on 3F4 material that indicates this could be so and (b) claims of delays in the tens of nanoseconds that also fit that assumption. There may be much slower effects for domain wall movement that could on the one hand improve matters but on the other hand since energy is involved it could make matters worse. Hence the need for experiments.
It may be that the previous measured effects are not due to mu or even domain wall movement at all, maybe the dielectric constant of ferrite is much greater than the figure of about 7 that I use. My trusty Reference Data for Radio Engineers says that dielectric constants as high as 100,000 have been measured on several ferrites having a small amount if divalent iron in their composition. So maybe the EM propagation previously seen is due to that, and it represents a weak transmission running ahead of the slow domain wall one. All I can say at the moment is a large 3F4 toroidal core in a magnetic delay transformer exhibited anomalous effects at 14MHz, and the use of bucking coils would considerably amplify that effect and make it appear at a lower frequency.
Smudge
[/quote]
OK after a missed delivery i have wound 1 coil of 32 turns on the new toroid.
Data Below
32 Turns of same wire.
LCR Test @ 100Hz
L = 4.45mH
Z = 2.79 Ohm
R = 0.0998 Ohm
Q = 28
LCR Test @ 10KHz
L = 4.366mH
Z = 274.41 Ohm
R = 0.785 Ohm
Q = 351
100pf 9mhz
205pf 6.7mhz
500pf 2.4mhz
1000pf 1.6mhz
2000pf 960khz
5000pf 403khz
10nf 200khz
20nf 88khz
50nf 36khz
So my calculated Inductance L is as follows for the above measurements
100pf 9MHz L= 3.1272uH
205pf 6.7MHz L = 2.7526uH
500pf 2.4MHz L = 8.7952uH
1000pf 1.6MHz L = 9.8946uH
2000pf 960kHz L = 13.743uH
5000pf 403kHz L = 31.193uH
10nf 200kHz L = 63.326uH
20nf 88kHz L = 163.55uH
50nf 36kHz L = 390.9uH
So it looks to me that we need to operate at no more than 400KHz and maybe 100KHz
PS the graph does not look right to me? Inductance seems to fall off to fast for this core, although is a lot better than my previous core.
OR
Maybe i need to do more measurements with large capacitance values, if that's the case then maybe we can only go in the 10's of KHz ???
OK Added more data points
Not sure what to make of this, my DC Inductance is way higher than my previous core but the rolloff seems to be still low between 10 & 40KHz?
100pf 9MHz 3.13uH
205pf 6.7MHz 2.75uH
500pf 2.4MHz 8.8uH
1000pf 1.6MHz 9.9uH
2000pf 960kHz 13.7uH
5000pf 403kHz 31uH
10nf 200kHz 63uH
20nf 88kHz 163uH
50nf 36kHz 390uH
100nf 13KHz 1.49mH
150nF 7.44kHz 3.05mH
200nF 6.31kHz 3.18mH
330nf 4.66kHz 3.53mH
430nf 3.9kHz 3.8mH
Anyway i will continue.
Next Step is to wind a second coil and feed the primary waveform into a digital monostable to square it up and same for secondary coil and then i will be able to scope the phase shift if it all goes to plan.
Hi Peterae,
I like your methodical approach. It gets results in the end.
The 2C90 core has a much higher DC mu than the other core, and this shows up as expected.
But the sharp drop off in calc. L at way less than 40 Khz doesn't conform to the datasheet at all, where complex mu falls off at around a Mhz.
This is really just a guess, but magnetic losses do drop off more rapidly in this material between 25 and 100 Khz at some given B. So maybe this has an effect on your L caclulations?
I found this interesting article by Jean-Louis Naudin about time delays in magnetic cores.
http://jnaudin.free.fr/dlenz/DLE22en.htm
He demonstrates a sizable magnetic domain delay in a laminated transformer I core.
He drove one end of a laminated power transformer I core with an air coil and then used a search coil, and hall probe to measure the magnetic delay. At a location of 22 mm down his laminated core, the actual magnetic field was 180 degrees out of phase.
This is not at all what Cyril is talking about. He is talking about an electromagnetic resonance, rather than a motional resonance (basically domains sloshing back and forth in a core).
But these domain movement resonances do show up pretty readily, so you could expect to see them in separated coils. It seems like in some ways that ou would be easy once you have a delay between pri and sec of a transformer, no matter what the cause. One could simply load the moving coil in his test with a given load, resulting a load phase lag, and then move the coil up and down until the phase lagged flux is adding to the drive flux instead of opposing it, at the location of the drive coil.
orthocoil
Hello ortho
Thanks for the Naudin link O0 & help
Back to the bench, i have 2 coils now and 2 primary coils each with 6 turns in bucking mode i will post data below this post a little later.
Next i will try for the phase delay and then check the mutual coupling.
Seconday windings
35 Turns each as previously detailed above
Connected series bucking
LCR @ 10KHz
L=378uH
R=0.2915R
Z=23.8R
Then
Primary on top 6 Turns each
Individual coil LCR Tests @ 10Khz
R=0.0462R
L=174.66uH
Q=241
Z=10.5R
Then
Primary LCR Test in series bucking mode @ 10KHz
L=15uH
R=0.0488R
Q=19.4
Z=0.94R
Cheers
Peter
OK the digital monostable did not work out, i think the amplitude varies slightly and makes any phase shift thats detected as false, i am triggering a schmitt at a certain voltage not zero crossing point :-\
So onto the mutual Inductance.
So i placed a 1 Ohm resistor in series with one of the main 32T coils and scoped across the resistor (Green Scope Chan)
and then scoped the other 32T coil (Yellow Chan)
I did this at 12.8KHz see photo curvsvol1
I did a scan up in frequency and found that about 1.2MHz the sig gen current would change phase with the second coil's voltage see photo
curvsvol2 and i have a link to a video of me adjusting the sig gen either side of this phase change.
https://www.youtube.com/watch?v=VwP4Sn8gwsw&feature=youtu.be
Quote from: orthofield on 2015.02.14, 16:49:23
I found this interesting article by Jean-Louis Naudin about time delays in magnetic cores.
http://jnaudin.free.fr/dlenz/DLE22en.htm
He demonstrates a sizable magnetic domain delay in a laminated transformer I core.
He drove one end of a laminated power transformer I core with an air coil and then used a search coil, and hall probe to measure the magnetic delay. At a location of 22 mm down his laminated core, the actual magnetic field was 180 degrees out of phase.
I can't accept that much delay occurring in transformer steel so I did a quick FEMM. simulation. JLN's hall probe is not measuring the flux in the core, it is measuring the flux outside the core, in fact the flux lines leaving the core normal to the surface. You can see in the simulation that there is a 180 degree change of that surface flux, but it has nothing to do with propagation delay. The red line is where FEMM plotted the normal component of B and you can see it starts off negative close to the coil then crosses over to positive some distance from the coil.
Have just got back from a weekend away so will look at Peter's results next.
Smudge
Hi Smudge,
Hmm, yes I agree with you about JLN's test. Most of the flux travels at right angles to the laminate and so it is more of a flux motional effect (interesting in itself!) rather than a domain movement.
It does show that there are at least two and maybe three mechanisms that can show up as a delay.
orthocoil
OK i placed a 1 Ohm NI Resistor in series with my primary and scoped across the resistor and coil, i had to invert the coil probe wave because of the common ground probe connections.
The waveforms can be seen at 41KHz in snap vipri Green Chan across 1 Ohm & Yellow across bucking primary.
Next the 1 Ohm load resistor across the 32T bucking coils as load see snap sec1ohm
PS don't worry Smudge if this does not workout to be OU, it fun to do and worthy of experimentation either way O0
So my scope computes RMS values for I & V
If i multiply these 2 together then i have a power input of 2.1225mW
As i just have a load resistance then presumably i can rake the RMS value of the voltage across the 1 Ohm and do V^2/R
Which gives me an output power off 144uW
I have seen a lot larger amplitude on my load resistor and this happens when i switch scales on my Sig Gen, i will investigate this as i do not believe there is an increase in power input but only a constantly changing frequency until it stabilizes, and as it seems to stabilize the amplitude also falls.
Maybe we need to change the load resistor value to match any possible negative resistance.
It looks like Peter's toroidal core is not the 3C90 ferrite he expected. From the measured inductance values I have calculated the effective mu and get the chart shown below. The LF mu is not far off the 3C90 spec, but the mu falls off rapidly above 10KHz. The 3C90 spec shows it flat to about 1Mhz. I think a complaint to Farnell would be justified.
Smudge
Edited to include comparison chart
Seems strange that the first 5 reading i took are good, these were done after the other wrong readings, i wonder if there is anything i could have done to get duff readings, so will re do the tests in a bit and post below before complaining O0
Are there any rules for finding the roll off, i am adjusting the Sig gen for max amplitude and then looking for when it starts decreasing in amplitude, i have a choice to use the frequency immediately it starts decreasing which is very small at first but then the decrease accelerates, i could register a point that the decrease really starts speeding up, at the moment i am looking for the smallest fall in amplitude and using this frequency value.
Can i ask how you are producing your graphs ???
OK done the measurements again, looks like there are a few false slight drops before the big fall off, not had a chance to look at the new data yet but here it is, hopefully this may be better C.C
500pf 1.75MHz Calc L = 16.542uH
1000pf 1MHz L = 25.33uH
2000pf 735kHz L = 23.444uH
5000pf 312kHz L = 51.056uH
10nf 97kHz L = 269.21uH
20nf 56kHz L = 403.86uH
50nf 20kHz L = 1.2665mH
100nf 12kHz L = 1.759mH
150nF 10.4kHz L = 1.5613mH
200nF 7.8kHz L = 2.0817mH
330nf 5.6kHz L = 2.4477mH
430nf 4.6kHz L = 2.9781mH
EDIT OK this still does not look good, is there anything i could be doing wrong, maybe i should not use a cap box with flying leads to the coil?
Why is my LCR meter saying 4.43mH @ 10KHz and the above is saying 1.56mH @ 10KHz?
Quote from: Peterae on 2015.02.16, 17:58:05
Are there any rules for finding the roll off, i am adjusting the Sig gen for max amplitude and then looking for when it starts decreasing in amplitude, i have a choice to use the frequency immediately it starts decreasing which is very small at first but then the decrease accelerates, i could register a point that the decrease really starts speeding up, at the moment i am looking for the smallest fall in amplitude and using this frequency value.
Can i ask how you are producing your graphs ???
I assumed you tuned the sig gen to the resonant point which would be a peak in the amplitude. I calculate the relative mu from the inductance formula L=N^2*munought*mu*A/l where A is the core cross section and l is the core length. These core dimensions are given in the data sheet in mm^2 and mm so you have to convert those to m^2 and m. I do this in an Excel spread sheet and use the chart function which allows you to use logarithmic scales.
How are you connecting the sig gen to the LC circuit? One way is to use a series LC and connect the sig gen across the series circuit, then look for maximum amplitude across the L or the C depending on which one connects to ground. Alternatively use a parallel LC but loosely couple the sig gen via a one turn loop. Tune for peak amplitude across the circuit. If you are not looking for the peak this could be why the results are wrong. Edit, and don't forget to include the scope probe capacitance if it becomes significant.
Smudge
Ahah i am connecting a cap across the L and connecting scope probe and Sig gen in parallel.
I will try a series LC connection tomorrow and tune for max PK O0
Hi Peterae,
This page basically reiterates what Smudge said about series measurements..
http://meettechniek.info/passive/magnetic-permeability.html
orthocoil
Fantastic thanks orthofield O0
Quote from: Peterae on 2015.02.16, 20:55:55
Ahah i am connecting a cap across the L and connecting scope probe and Sig gen in parallel.
I will try a series LC connection tomorrow and tune for max PK O0
The output impedance of the sig gen is generally very low (like 50 ohms) and when shunted across a parallel LC circuit it lowers the Q so much that resonance is not easily detected. A series LC across the sig gen could work where at resonance the LC impedance is lower than that of the sig gen, so there you look for a minimum signal across the sig gen. But if you look across the L or C then the voltage there peaks at resonance. But again the impedance of the sig gen lowers the Q so you get a very broad peak. The parallel resonant LC circuit with some loose (1 turn) coupling from the sig gen will have a much greater Q so you get a very sharp peak easily found. There are many techniques for coupling into both series and parallel circuits that work better but it would read like a text book if we went into them.
Smudge
Quote from: orthofield on 2015.02.16, 22:14:28
Hi Peterae,
This page basically reiterates what Smudge said about series measurements..
http://meettechniek.info/passive/magnetic-permeability.html
orthocoil
The method shown in that link does not use resonance, it measures the current through L and the voltage across L. Then since Vmagnitude=imagnitude*omega*L you can get the inductance as L=Vmagnitude/(imagnitude*omega). With the resonance method you don't need to measure any values, just tune for a peak, note the frequency then use the resonance formula. A good cross check is to use both methods. O0
Smudge
OK i tried loose coupling the Sig Gen 1 loop through centre of toroid with a parallel Cap box across the Inductor and wow sharp peaks found, my problem now is even the 15pf of the scope probe limits the top frequency i can test at.
I measured my scope pf and my lcr reads 15.88pf
Just Probe 15.88pf 308khz 248v Calculated Inductance = 16.815mH
20pf + 16pf probe =36pf 263khz 248v pk-pk L=10.172mH
30pf + 16pf probe =46pf 242khz 248v pk-pk L = 9.4027mH
50pf + 16pf probe =66pf 208khz 225pk-pk L = 8.8709mH
150pf + 16pf probe = 166pf 155khz 221v pk-pk L=6.3514mH
250pf + 16pf probe =266pf 138khz 210v pk-pk L=5.0004mH
550pf + 16pf probe = 566pf 89khz 189 pk-pk L =5.6499mH
1nf 69.4khz 167v pk-pk L = 5.2592mH
2nf 48.1khz 139v pk-pk L = 5.4742mH
5nf 30.5khz 105v pk-pk L = 5.4459mH
10nf 21.6khz 82.8v pk-pk L = 5.4292mH
20nf 15.6khz 62v pk-pk L = 5.2043mH
50nf 9.77khz 39.5v pk-pk L = 5.3843mH
I see the inductance going up as the capacitance goes down, this surely is a sign there is stray capacitance acting on the circuit and giving false measurements, i could try using one of the primary low turn coils instead which should allow me to go higher in frequency?
EDIT OK just tried the low turn primary coil on top so can still only go up to 357khz with that coil.
just probe 357khz
50pf 352khz 45pk-pk
350pf 320khz 45.5pkpk
550pf 290khz 45pkpk
The 3C90 mu does increase reaching a peak at about 400KHz and then it starts to decrease. However your results are showing a much larger increase there see chart. This may be correct since other ferrites are known to have an increase due to a ferromagnetic resonance, see for instance the curve for TDK PE22 in the attached paper. That paper attempts to show the possibility of using the permeability peak to get OU so you may get led down another avenue if you discover a large ferromagnetic resonance with this core. ;)
Smudge
And while we are on the subject of ferromagnetic (or ferrimagnetic) resonance here is another paper you may find interesting. Enjoy :)
Smudge
Hi Smudge,
I haven't looked at your 'precession' paper yet...
Still examining the paper on using the permeability peak, which I find quite interesting.
I can imagine a circuit where the core is in a tank circuit along with a varactor or other frequency changing element. A pulse is introduced at the peak mu frequency, adjusted by the biased varactor. As soon as the decaying oscillation starts, the varactor bias is shut off, and the frequency drops. With the drop in frequency, the increase in mu causes an increase in current in the coil which can be tapped for power.
I also wonder, if a weak signal is introduced at this high frequency permeability peak, will the presence of this signal control the low frequency mu? It's pretty well known that mu can be increased, and hys. losses decreased by superimposing a small HF signal on a core. The superimposed signal can be smaller magnitude than the LF signal. This was patented in the 1920s.
Also, I'm still trying to find a patent in my files that shows a method for changing mu of a 'dielectric' ferrite by superimposing an electric field on it.
orthocoil
OK thanks Smudge so whats my next move i need help working through this stuff O0
If you point me i will do my best to do the bench work ;)
I almost have the digital monostable fully working now, just one more problem to sort in code and i will be flying with nS pulses, still not yet sure how low it goes, but i do get a pulse when it's set above 6nS but the pulse is wider, more tests are needed when the code is sorted to see how well the 6amp fet driver performs.
I could also go back to my first toroid and run the tests on that one using the loose coupling.
Quote from: Peterae on 2015.02.17, 21:18:33
OK thanks Smudge so whats my next move i need help working through this stuff O0
If you point me i will do my best to do the bench work ;)
I almost have the digital monostable fully working now, just one more problem to sort in code and i will be flying with nS pulses, still not yet sure how low it goes, but i do get a pulse when it's set above 6nS but the pulse is wider, more tests are needed when the code is sorted to see how well the 6amp fet driver performs.
I could also go back to my first toroid and run the tests on that one using the loose coupling.
Well you could extend the measurements to higher frequencies by putting a 1K resistor between your sig gen and the 1 turn loop, then connecting the scope probe across the 1 turn loop. That enables you to see the resonance peak but now the probe capacitance is not across the coil so you can use smaller values there. A simple way to make small capacitors is to twist some magnet wire into a twisted pair then you get capacitance between the two wires. You can cut the twisted pair into smaller lengths to get smaller values, but of course you need to measure each one to know what the capacitance is. Or measure a long length to establish the distributed capacitance value (pF per metre) then cut to the required length. It would be interesting to see the full mu v. frequency curve to see if we could use that permeability peak somehow.
One thing is clear, the new core will enable you to work at frequencies up to 1MHz which is what we wanted. So you might be tempted to make the whole bucking coil transformer thingy and do some power transfer measurements at those higher frequencies.
Smudge
Quote from: orthofield on 2015.02.17, 21:13:14
Hi Smudge,
I haven't looked at your 'precession' paper yet...
Still examining the paper on using the permeability peak, which I find quite interesting.
I can imagine a circuit where the core is in a tank circuit along with a varactor or other frequency changing element. A pulse is introduced at the peak mu frequency, adjusted by the biased varactor. As soon as the decaying oscillation starts, the varactor bias is shut off, and the frequency drops. With the drop in frequency, the increase in mu causes an increase in current in the coil which can be tapped for power.
I also wonder, if a weak signal is introduced at this high frequency permeability peak, will the presence of this signal control the low frequency mu? It's pretty well known that mu can be increased, and hys. losses decreased by superimposing a small HF signal on a core. The superimposed signal can be smaller magnitude than the LF signal. This was patented in the 1920s.
Also, I'm still trying to find a patent in my files that shows a method for changing mu of a 'dielectric' ferrite by superimposing an electric field on it.
orthocoil
You almost got it, but your varactor would have to
lower the capacitance to create an increase in frequency to get the increased permeability. Don't know about the superimposed HF but it would be worth trying. Perhaps this permeability peak idea should be on a different thread since it is not associated with bucking coils (but there again this thread title does not mention bucking).
Smudge
Hi Smudge
Thanks for the help.
I used thicker insulated wire and twisted it and then measured the cap using my LCR each time, the problem is that with no capacitance (No wire & open coil) i can still only go up to 378KHz, i have 4 coils all open on this toroid, 2 primary & 2 secondary.
Here's the data, going off now to do some power tests, i will choose 300kHz for a starter O0
wire 33.55pf 277kHz
30.74pf 284kHz
28.94pf 284kHz
26.94pf 287kHz
23.7pf 297kHz
19.16pf 304kHz
15.95pf 312kHz
12.71pf 328kHz
8.65pf 342kHz
5.7pf 347kHz
2.98pf 362kHz
no capacitance 378kHz (Open circuit coil)
Hi Smudge,
The way I was thinking of this was that the circuit would start at the high frequency with the initial impulse, and then the frequency would be dropped into the range where mu was lower. The reduction of mu (and L) would lead to a rise in current in the decay oscillation (parametric amplification).
orthocoil
OK i took scope shots of first across the primary CSR 1 Ohm & Across L at different frequencys and then went back and took load snaps at the same frequencys.
as follows at
312khz
500khz
762khz
1.02mhz
1.52mhz
2.02mhz
2.5mhz
2.98mhz
3.91mhz
Pin = Vrms * Irms *cos(phi)
Pout = Irms^2 * R R=1 Ohm so Pout=Irms^2
COP=Pout/Pin
312khz Vrms=186mv Irms=64.4ma VLrms=12.4mv Pin=11.978mW Pout=153.76uW COP 0.0129
500khz Vrms=283mv Irms=64.4ma VLrms=12.7mv Pin=18.2252mw Pout=161.29uw COP 0.00884
762khz Vrms=418mv Irms=64.2ma VLrms=13mv Pin=26.8356mw Pout=169uw COP 0.00629
1.02mhz Vrms=552mv Irms=62.7ma VLrms=13.7mv Pin=34.6104mw Pout=187.69uW COP 0.0054229
1.52mhz Vrms=758mv Irms=60.7ma VLrms=14.6mv Pin=46.0106mw Pout=213.16uw COP 0.004633
2.02mhz Vrms=967mv Irms=58.2ma VLrms=15.9mv Pin=56.2794mw Pout=252.81uw COP 0.004492
2.5mhz Vrms=1.12v Irms=55ma VLrms=18.4mv Pin=61.6mw Pout=338.56uW COP 0.005496
EDIT** i think i should have used I^2*R for power in the load as the voltage is really a current, but as my resistor is 1 Ohm it does not alter my results, i will change the above text to reflect this later after work O0
2.98mhz Vrms=1.27mv Irms=51.5ma VLrms=19.5mv Pin=65.405mw Pout=380.25uW COP 0.005814
3.9mhz Vrms=1.53mv Irms=39.8ma VLrms=21.9mv Pin=60.894mw Pout=479.61uw COP 0.007876
Peter,
Your Pin should be Pin=Vrms*Irms*cos(phi) where phi is the phase angle between V and I. It appears you haven't measured phi. Did you check that phase angle? If it is well away from 0 degrees it will seriously affect the result. Measuring that phase angle can be problematical when you use the voltage across a NIR for getting the current, since you need a scope that can do waveform subtraction.
Edit. I have just looked at your waveforms and it is clear that the phase angle between input V and I is close to 90 degrees so the input power is way down on those quoted.
Edit 2. In fact it is so close to 90 degrees that the input power is almost zero, so great difficulty in getting an accurate measurement. As the input impedance is close to being purely inductive I suggest you concentrate on the lower frequency range between 300KHz and 1.5Mhz. Use a series capacitor to resonate the input L at the chosen frequency so that the input current and voltage are in phase, then use the Pin=Vrms*Irms formula. Of course the capacitor must be between your NIR and the coil, and the voltage must be taken across the series C and coil.
Edit 3. And you could try higher values of load resistor.
Edit 4. Having blown up your images it looks like the phase angle is about 80 degrees so your input powers are all overstated by about 6. Improves the COP's slightly. I would expect better COP's with higher load resistance.
From your inductance measurements using resonance it is clear that the coils have a self resonance indicating self capacitance and that is not surprising. So the apparent large rise in inductance at the higher frequencies is an artefact. I think we can say that the cores meet the 3C90 spec and are good up to 400KHz and beyond. I am playing with the negative resistance calculation to include the losses expected form the core using the 3C90 complex permeability data. They give u' and u" that are the real and imaginary components of the mu. So the inductance formula using u' gives the inductance value and that same formula using u" and multiplied by omega yields the effective core losses as a resistance value in series with the L (I think :-\ ). I'll post the results when done.
Smudge
Hi Smudge Thanks.
so if i need to take into account the phase angle then the above yellow trace would need inverting, and it looks like there's an offset for some reason, the yellow trace does not look as if on the zero line despite the cursor saying so and this would give a false phase angle, i will try a calibration, poor scope has had a hammering in the past.
QuoteYour Pin should be Pin=Vrms*Irms*cos(phi) where phi is the phase angle between V and I. It appears you haven't measured phi. Did you check that phase angle? If it is well away from 0 degrees it will seriously affect the result. Measuring that phase angle can be problematical when you use the voltage across a NIR for getting the current, since you need a scope that can do waveform subtraction.
My scope does not do phase angle, although it does have a basic math function, i cannot do maths on the rms values but the waveforms on the scope probes i can.
I thought the phase angle in an inductor should be 90Deg, so surely it is safe to use 90 Deg in our above scope shots?
Lets choose 750KHz to work on, if there is a way to work out the optimum load that could help me.
EDIT
i will edit the above results to show Pin using *cos(phi)EDIT that did not work out as cos(90) = 0 C.C So i now see what you mean our input power needs to be gained by other methods or by measuring the angle precisely which is not possible with my scope, so i will try your series cap method O0
I suspect we will be limited by the self capacitance regarding our trial frequency, if i calculate the series cap value using my LCR inductance of 4.45mH then i get 10pf, we already know we cannot get parallel LC above 370khz, i will do some tests but i suspect we may need to test at 300khz.
Peter,
The series cap does not tune with the secondary inductances so forget the 5mH. Measure the input inductance of your bucking primary windings (100's of uH) and tune to that. You'll soon know whether it is right because you will see the V and I in phase on your scope (in fact you can adjust frequency to get them in phase).
You can deduce the phase on your scope by taking the timing from zero cross overs of V and I. I did this not by actual times but by graticule markings. Then since the graticule distance for a full cycle is easy to determine, and that represents 360 degrees, you get the phase from 360*phasegraticule/cyclegraticule (edited cos I got it wrong :-[ ).
Smudge
Hi Peterae-
If I may suggest a different test layout that will simplify your resonance testing. See the attached schematic which is pretty much self explanatory. The idea is to create a ringing between the known capacitance Cx and the unknown inductance Lx which can then be easily measured with a scope automatically or manually with cursors. The scope probe capacitance is in parallel with Cx.
Also attached is a scope shot of a test using this circuit on a 51mm toroid in P7070 material with 9 turns on the core and Cx is only the scope capacitance of 8pfd along with I'm sure a few pfd of strays.
Hope this is of some help.
partzman
Primary LCR Test in series bucking mode @ 10KHz
L=15uH
R=0.0488R
Q=19.4
Z=0.94R
So for 750khz thats 3.0021nF O0
Thanks
Not got to the bench yet but will head down shortly to try it out
OK
This test used a 100 OHM load, the 100 Ohm was metal film hopefully thats ok, the primary NIR was still 1 Ohm
I will describe the setup first for you to check i understood correctly.
My sig gen positive connected to one end of NIR i have my yellow probe either side of NIR, my cap connects to other end of NIR as does my other scope probe earth, so both scope probe earths are together, the other side of the cap connects to inductor and the other end of inductor connects to the earth of the sig gen and my green probe tip.
Green chan is inverted, so green chan is across series LC and yellow probe across NIR
I had to set my cap box to 16nF to obtain a frequency of approx 771khz where i could adjust to get the phases of current and voltage to align.
So first shot is green Voltage across LC and yellow across 1 Ohm NIR res 771khzpriyeli-greenv
Then i dosconnected the green chan leaving the yellow across the 1 Ohm primary NIR resistor and connected the green across the 100 Ohm load which gives the second shot sec100ohmload771khzgreenloadyellowcur
So Green is across 100 Ohm load and yellow the primary current. PS i had the load probe wrong way hence phase inversion.
Not crunched any numbers yet, if i get a chance i will append the results O0
EDIT
green 228mv
yellow 52.9
Pin=12.0612mw
Pout = V^2 / R
Pout = 7.3mW
Ok i was right to use V^2/R for Pout because if it's I^2*R then i have a Pout of 73Watts LOL and my little resistance should have been glowing red.
Tomorrow night i need to try some higher resistance loads as a 1OHM load gave me
Pout = 121uw
Pin = 12mw
Peter,
From your description
QuoteMy sig gen positive connected to one end of NIR i have my yellow probe either side of NIR, my cap connects to other end of NIR as does my other scope probe earth, so both scope probe earths are together, the other side of the cap connects to inductor and the other end of inductor connects to the earth of the sig gen and my green probe tip.
I don't think you are measuring what you think you are measuring. Can you supply a diagram in case I am misreading your description. I also think you have serious issues with the earth connections of scope and sig gen shunting away signals.
Smudge
Hi Smudge see schematic, my DSO is connected to a laptop on bAttery powr and as the s econdary & load is not connected to anything else i did not think it would matter if the scope probe earth was connected to anything?
I dont need to monitor the primary current while doing the load shot, so i will do jujst the load connected on it's own the primary reading would not change.
OK 3 Tests.
1MHz 200 Ohm load
1Mhz 510 Ohm load
744KHz 510 Ohm load
All primary waveforms are Green across LC & Yellow I across 1 Ohm NIR
Secondary is green with yellow probe disconnected.
1MHz 200 Ohm Load
Primary 1mhz200load-grelc-yeli
V=383mv
I=54ma
Pin=20.682mw
Secondary 1mhz-200ohmload
V=1.66V
Pout=13.778mw
COP=0.666
-----------------------------------
1MHz 510 Ohm Load
Primary 510ohm-pri-glc-yi
V=749mv
I=46.1mv
Pin=34.5289mw
Secondary 510ohmload1mhz
V=3.41V
Pout=22.80mw
COP=0.660
-----------------------------------
744KHz 510 Ohm Load
Primary 744-510ohm-pri-glc-yi
V=689mv
I=44.3mv
Pin=30.5227mw
Secondary 744-load510ohm
V=3.52V
Pout=24.29mw
COP=0.7958
Away from home in motorhome (RV) using laptop on low battery so might not get this post finished. Although your DSO is on battery power its chassis will have a self capacitance to earth so there will be shunt path across to the sig gen earth. This will be more prominent at the higher frequencies and will affect only the input measurements, effectively you have placed an unwanted capacitor across the input terminals that could be much greater than that of a scope probe. If your scope can do subtraction you can put the NIR at the earthy end of the primary, then both scopes probes connect to the common earth. One scopes the NIR voltage and the other scopes the sum of the NIR voltage and the wanted input voltage. So a subtraction gives you the input voltage. Then you eliminate any unwanted shunt paths.
I note your COP's are now quite realistic whereas before they were dismal. It is worth doing finer frequency increments to see if there is a sweet spot giving maximum COP. The graph of COP against frequency would reveal whether the math behind the negative resistance is correct since that definitely shows a peak at a certain frequency. Then it is a matter of accounting for the positive losses pulling the COP below 1.
Smudge
QuoteThe graph of COP against frequency would reveal whether the math behind the negative resistance is correct since that definitely shows a peak at a certain frequency.
Any preference for load resistor value?
OK i used 510R
215khz i=72.4 lcv=675 load=4.6 pin=48.87mw pout=41.49mw cop=0.849
245khz i=72.4 lcv=757 load=4.90 pin=54.80mw pout=47.08mw cop=0.859
297khz i=72.3 lcv=875 load=5.17 pin=63.26mw pout=52.41mw cop=0.828
378khz i=68.5 lcv=1.04 load=5.78 pin=71.24mw pout=65.51mw cop=0.920
510khz i=67.5 lcv=1.06v load=5.8 pin=71.55mw pout=65.96mw cop=0.922
744khz i=66.7 lcv=1.17 load=5.76 pin=78.04mw pout=65.05mw cop=0.834
892khz i=63.8 lcv=1.2 load=5.77 pin=76.56mw pout=65.28mw cop=0.853
1.14mhz i=63.3 lcv=1.28 load=5.6 pin=81.66mw pout=61.49mw cop=0.753
1.32mhz i=61.6 lcv=1.22 load=5.25 pin=75.15mw pout=54.04mw cop=0.719
1.56mhz i=62.5 lcv=1.26 load=5.16 pin=78.75mw pout=52.20mw cop=0.663
1.84mhz i=63.7 lcv=1.29 load=5 pin=82.17mw pout=49.02mw cop=0.597
2.15mhz i=57.6 lcv=1.16 load=4.40 pin=73.89mw pout=37.96mw cop=0.514
3.30mhz i=56.2 lcv=1.25 load=3.4 pin=70.25mw pout=22.66mw cop=0.323
4.81mhz i=42.4 lcv=1.45 load=2.49 pin=61.48mw pout=12.16mw cop=0.198
6.76mhz i=21.2 lcv=2.08 load=1.31 pin=44.09mw pout=33.65mw cop=0.763
Not sure what happened at 6.76MHz i will look at that sudden jump up a bit more
EDIT
The graph was not very good so have now replaced it with a better one.
Thanks for all those measurements. The sudden jump at 6.76MHz is almost certainly due to a resonance outside our area of interest. If you ignore that then we have graph rising to a peak value then falling off at the higher frequencies, which is exactly what I would expect. It is that rise to a peak value that is of interest since that is indicative of some internal effect that eventually gets overridden by the HF core losses. The two charts here show (a) the complex permeability values that were derived using math functions to fit the actual ones and (b) the negative resistance that appears using the formula in my original paper. The actual values shown are of no interest since I can change a small parameter and get widely different ones. What is of interest is the value increasing with increasing frequency (as per my formula) but then getting overridden by the increasing positive value from core losses. I think your results show this tendency.
So I suggest you now concentrate at a fixed frequency where the COP is maximum between 378 KHz and 510 KHz. Then create a plot of COP against different load resistor values. You should find an optimum value where COP is greatest. Since you are already at a COP greater than 0.9 this bodes well for getting near to unity even if not beyond that. When you consider that (a) the core has losses and (b) the coils have losses then a COP near unity could well mean that there is an OU effect going on. You might then try Litz wire to minimise coil losses. Anyway it appears you now have something tangible to get your teeth into. Well done!
Smudge
Thanks Smudge
Good plan, loads next then O0
Still trying to track that peak in COP
did some more earlier so it looks like i need to go a little lower in frequency yet somewhere between 297 & 631khz to zoom in on that peak a bit.
631khz i=70.1 lcv=1.18 load=6.03 Pin=83.78 Pout=71.30 COP=0.851
661khz i=70.9 lcv=1.21 load=6.11 Pin=95.59 Pout=73.20 COP=0.766
702khz i=70.9 lcv=1.22 load=6.15 Pin=86.49 Pout=74.16 COP=0.857
I just crunched some data from earlier in the day, this lot was done with a 100 Ohm load.
The COP is all over the place and i think it's because of the lower amplitude readings introducing more readable errors O0
load 100ohm
403khz i=63.2 lcv=261mv load=1.14 Pin=16.49 Pout=12.99 COP=0.787
480khz i=63 lcv=267 load=1.14 Pin=16.82 Pout=11.14 COP=0.662
543khz i=63.3 lcv=269 load=1.14 Pin=16.90 Pout=12.99 COP=0.7686
625khz i=62.8 lcv=270 load=1.13 Pin=16.96 Pout=12.77 COP=0.753
694khz i=62.9 lcv=276mv load=1.08 Pin=17.36 Pout=11.66 COP=0.672
781khz i=61.4 lcv=271mv load=1.1 Pin=16.64 Pout=12.77 COP=0.767
961khz i=63.7 lcv=293 load=1.15 Pin=18.66 Pout=13.23 COP=0.709
1.39mhz i=61.2 lcv=293 load=1.09 Pin=17.93 Pout=11.88 COP=0.663
1.79mhz i=61 lcv=311 load=1.07 Pin=18.97 Pout=11.45 COP=0.604
PS i did try your subtraction idea but it did not work well on my scope, current is 10's of mv and LC voltage is volts, subtract the 2 and you loose the current as my scope only does 2 digits
Peter,
It seems that lower resistance causes lower COP so I would be tempted to go back to your 510 ohm load and confirm the 0.922 COP at 510 KHz. That is assuming your written 510R means 510 ohms. Then stay at that frequency and try different loads to get higher COP. There is bound to be an optimum load where the COP is greatest.
Smudge
Something interesting is happening, i just went back and started re doing tests with the 510 ohm load and every test and re test is COP 1 or slightly greater?? at one particular frequency which is the first i went to try.
looking for errors but i am doing exactly what i did yesterday, will keep looking for the error :P
Quote from: Peterae on 2015.02.23, 18:23:07
Something interesting is happening, i just went back and started re doing tests with the 510 ohm load and every test and re test is COP 1 or slightly greater?? at one particular frequency which is the first i went to try.
looking for errors but i am doing exactly what i did yesterday, will keep looking for the error :P
Dear Peterae.
This might sound like a daft question, but, how different is the weather today ??
Please humour me. ;)
Cheers Grum.
Peter
you can remove this post
However I must ask a similar question regarding weather and perhaps
conditioning the environment around your lab.
as you may recall Tinman was getting weather events [rain] immediately after
and in several cases During His Star in a jar experiment which were captured on Video.
Seemed the longer he played with that little Fusion bottle[over time] the more it Manifested.
I know you don't have a Tin roof like he does,and yes I know it rains MUCH more in the UK however it never hurts to Note these things.[temp humidity and pressure]
sorry for the interruption,however those were very funny times...
started calling him RainMan.. 8)
LOL
It was only 3 degrees C when i started work been down there over an hour and the COP>1 has gone, it just went, probably down to temperature change in the scope or something, this is an uncalibrated scope although i did run it through it's own calibration routine last night.
I kept doing checks constantly and checked the cop each time altering the frequency slightly and then my Cops went down here's a list of the tests during this time, i have included the first set of COP=1 scope shot. O0
362kHz i=65.9 lcv=1.05 load=5.94 Pin=69.19 Pout=69.18 COP=0.999
390kHz i=64.7 lcv=1.05 load=5.97 Pin=67.93 Pout=69.88 COP=1.028
416khz i=63.3 lcv 1.07 load=5.97 Pin=67.73 Pout=69.88 COP=1.032
462khz i=66.8 lcv=1.08 load=5.87 Pin=72.14 Pout=67.56 COP=0.937
390khz i=68.1 lcv=1.05 load=5.80 Pin=71.51 Pout=65.96 COP=0.924
396khz i=68.3 lcv=1.05 load=5.84 Pin=71.72 Pout=66.87 COP=0.932
Also note the little squiggle on the bottom of the sine this is my signal generator getting old and maybe also a problem slightly.
Don't get over excited i have been using 510 as my resistance value for output power calcs but i think when i measured the other day it was about 514ohms and 1%, i was not meant to be any where near COP=1 so have not bothered with the fine stuff so far, i only wanted to start trying different loads and was stopped in my tracks ;D
Quote from: Matt Watts on 2015.02.23, 19:28:33
Awesome Peter!
What do you think Smudge? Cold temperature reducing the resistance even more?
Dear All.
Or an increase in humidity !! ;)
Last year I had a single event where I had an Ionic wind that had my hair standing on end, the humidity changed and the effect was never seen again !!
Cheers Grum.
Yep it's gone for now.
Been trying different loads, the trouble is that a different load shifts the frequency so i have to adjust the series cap value to bring my primary I & V back in phase.
I also decreased my sig gen drive amplitude to try to get rid of that little glitch at the bottom of the waveform.
Results I've started measuring my load resistance for more accurate results.
Load=1.096 KOhm
load alters frequency
same cap new freq = 271khz cap=28nf
i=68.2 lcv=725mv load=6.68 Pin=49.45 Pout=40.71 COP=0.823
adjusting cap to bring back to 416khz still 1.096KOhm load
416khz cap=15nf
i=61`lcv=1.13 load=8.19 Pin=68.93 Pout=61.20 COP=0.888
new load = 823.1Ohm
416khz Cap=18nf
i=61.4 lcv=1.14 load=7.12 Pin=69.99 Pout=61.59 COP=0.879
new load = 680.1 Ohm
416khz Cap=21nf
i=61.3 lcv=1.09 load=6.33v Pin=66.82 Pout=58.92 COP=0.882
new load = 467.5 Ohm
416khz Cap=27nf
i=63.3 lcv=941mv Load=4.91 Pin=59.57 Pout=51.57 COP=0.866
I should have tried 510 again, it appears that might be a peak in COP.
It looks like the reason for the high cop is the decreased current measurement, therefore i conclude a possibility that the NIR when cold is a lower value. it only takes a few mv drop as this is multiplied by the larger voltage.
It looks like a precision resistance here would be good, but i do not have to to hand.
EDIT
I wonder if i can increase this resistance to 10 Ohm to get an increased current resolution without affecting things too much, if i can get my current measurement into the volts range i would then be able to use Smudges subtraction measurement system.
I think it more likely that your scope calibration is wandering, especially the channel operating at maximum gain (i.e. measuring the NIR voltage). If you used the same channel for all measurements then although the actual power values may be wrong the ratio forming the COP would not change. But then you would have to switch the gain and my experience of scopes tells me that action can change calibration so perhaps that wouldn't work. I see no reason why you should not use a higher value NIR except that it will affect the power you can suck out of your signal generator.
Smudge
The fact that the input inductance changes with different load resistors could be significant. Normally one would not expect this and it seems you have got a 1.8 ratio inductance for a 2.34 ratio load resistor. If nothing else you may have discovered a method for creating variable inductance without the need for moving parts :D .
Smudge
OK will try a bigger NIR
QuoteIf nothing else you may have discovered a method for creating variable inductance without the need for moving parts
Sounds good LOL, but is there any way of understanding why?
I wonder if the ratio is related to the primary vs secondary turns ratio.
Quote from: Peterae on 2015.02.24, 17:52:44
OK will try a bigger NIR
Sounds good LOL, but is there any way of understanding why?
I wonder if the ratio is related to the primary vs secondary turns ratio.
No. The effect is related to a time or phase delay between input and output which is exactly what we are looking for to get OU effects. This delay alters the input current v voltage phase so a resistive load on the output appears at the input to have a reactive component, in this case inductive. I have shown elsewhere that a magnetic delay acts like a line having a reactive characteristic impedance (whereas classical delay lines have a resistive characteristic impedance) and if you terminate it in a capacitance it reflects as a negative resistance at the input. So it appears to me that you would benefit from adding capacitance either across or in series with your load. IOW instead of adjusting your input to get zero phase there by changing the series capacitance there, do it at the output instead. What I mean is play with different capacity values on the output while still looking at the input phase angle and adjusting it to zero. You might get some interesting results.
Smudge
QuoteIf nothing else you may have discovered a method for creating variable inductance without the need for moving parts.
I could be wrong, but I think it is normal for the primary inductance to change with secondary load resistance. Consider the limit case of a
ideal transformer with secondary either open or shorted. Primary inductance should go from maximum to zero.
In fact the uncoupled inductance of a transformer can be measured by shorting the secondary and measuring the inductance of the primary. It will show the uncoupled inductance or "leakage" inductance. Coupled primary and secondary inductance disappears with the addition of the short, leaving only the uncoupled inductance.
A magnetic transport delay between input and output negates the ideal transformer scenario and interesting effects may occur, which is what Smudge has said all along.
Hi ION,
I agree with you there. Attached is a patent with bucking coils where the reactance is controlled by a resistor.
Impedance transforms show that you can vary a pure R and get a pure L or C change in a network in some cases.
This was also used in some transmission line FM modulators where the terminal R was varied to get a variable reactance, which could go from L or C, at the input.
I'll post a scheme on my bench, where just varying the resistance can cause parametric oscillations...
orthofield
Quote from: orthofield on 2015.02.24, 19:21:17
Hi ION,
I agree with you there. Attached is a patent with bucking coils where the reactance is controlled by a resistor.
Impedance transforms show that you can vary a pure R and get a pure L or C change in a network in some cases.
This was also used in some transmission line FM modulators where the terminal R was varied to get a variable reactance, which could go from L or C, at the input.
I'll post a scheme on my bench, where just varying the resistance can cause parametric oscillations...
orthofield
Thanks Orthofield
I'll post my comments on the patent on your bench so not to disrupt this thread
Regards, ION
Did not get much done tonight.
I fixed a cap value in series with my primary inductor and used a 27nF
I first put a cap box across my 470 ohm load and could adjust the phase of my primary current and voltage as suspected, but when i went to scope across the parallel secondary R&C i had no waveform to measure.
I then tried the cap box in series with the secondary load resistance, again it was possible to adjust the primary phases by adjusting the secondary cap box, nothing really seen, as i now have a series LC on my primary and also a series LC on my secondary i could not fully match the phases on the primary and secondary to do any meaningfull power measurements.
Here's some notes made
if i adjust the secondary series cap value to get voltage across this cap and voltage across secondary load resistance in phase then my voltage across the secondary series cap goes to almost zero, IE very small noisy looking just about recognisable sine on 10mv/div.
at this point my voltage across secondary series cap (just recognisable) is in phase with my primary voltage across the NIR and nearly in phase with my primary lcv but not quiet.
Nothing significant seen.
I was thinking of a small value capacitor across the load, not one that would shunt away all the power. When you are moving from one experimental set-up to another you are making changes that are too large, I think you need to move in smaller increments. Like you had a 467.5 ohm load and a 27nF series capacitor on the input to give a COP of 0.866 at 416KHz. What happens if you add a teeny weeny capacitor across the load and then adjust the 27nF to make good the phase angle there? Does the COP go up or down? If no change then try a slightly larger one on the load. Proceed in small steps. If things are going the wrong way, like COP going down, then reverse the action and do the opposite. The opposite of adding capacitance is adding inductance. You must feel your way step by step.
Smudge
Thanks Smudge
Tonight i really wanted to work out if any of my equipment is in calibration.
I have 2 scopes a mains Owon 20MHz scope and the 200MHz Hantek DSO laptop powered i have been using up to now, i prefer the hantek as it is isolated by battery power.
I have suspected my owon was out of calibration because it has a 5V Squarewave gen built in and when i hook that up i get 5.2V Pk-pk.
So tonight i tried using first the Hantek and then the Owon
I changed my NIR to a 10 Ohm carbon film and selected the 10 Ohm using my precision LCR meter for almost exactly 10 Ohm
My load is measuring 516 Ohm and will use this for a while.
I tried the subtraction method and it works pretty good now my current waveform is larger but i am still hesitant because of the 2 digit limitation.
anyway i got 2 totally different results using the hantek & owon, i used just 1 probe to measure each variable
Hantek
1 probe to measure each variable
500KHz 20nF I=636mv LCV=1.03 Load=5.75 Pin=65.51 Pout=64.07 COP=0.978
Using Owon
500KHz 20nF I=837.1mv LCV=1.202 Load=6.210 Pin=100.6mw Pout=74.7 COP=0.7423
So i then though how can i tell how in calibration each scope is, so i then set my signal generator to 50Hz and put a dvm on it to read DVM 7.33V
and the 2 scopes read as follows
Owon 7.414V RMS
Hantek DSO 7.03V
So it looks like the Owon is fairly close and it does 3 decimal places, so it looks like i now need to start the tests again using the owon.
I will do all the frequency's again to look for a COP peak and then go from there. O0
I need a new scope really :)
Peter,
Those calibration figures don't account for the different COP's (ignoring your 74.23 COP which is a math error C.C ) so I think the ground connection to the mains scope might be doing something. You might track this down by using your Hantek to measure something then just connect the mains scope ground and see if anything changes.
Smudge
From Peter
QuoteI need a new scope really
Your need will be addressed by the community soon.
Peter, you have been generous in funding this site for many years without any help that I know of, now it is time for the community to give back to you.
P-Prof, and Chet.....if you agree, lets start beating the bushes. If 25% of the membership that use this site gives $10 to $20 it should easily cover a new scope for Peter.
I can think of no more deserving recipient than Peter. In addition to funding and maintaining this site, his experiments are predominately in line with the OUR mission statement, i.e the quest for OU. There is no advertising on this site and Peter has stated that there never will be.
Peter, do you have a Paypal account that we can make a direct deposit?
Regards
ION
Great idea! count me in for $50 for a scope for Peter!
--Steve
PS - I'm going with visiting family today... back later
Thanks for your offer ION & PhysicsProf, It makes it worth while running the site with such good members like yourselves making use of it for research, still no need for donations though, although i am thinking if i send someone in the US the money and P&P money maybe someone could post it on to me.
Smudge
Quote(ignoring your 74.23 COP which is a math error Roll Eyes )
Oops yes i got the decimal place in the wrong place 0.7423 will go back and edit that in the original post. Thanks :-[
I'm not convinced about the earth problem because i tried several methods of obtaining the measurements, one being to use the Sig Gen earth as the scope earth point, then measure LCV and then Across Sig gen input, using a calculator to subtract LCV from Sig Gen gave me my Current I.
If i do this from now on then i don't think there can be any problem, just means i have more number crunching to do, i will try knocking up a spreadsheet to do the hard work. O0
Peter
Please let us do this for you...
I just hung up with the Vendor and they are sold out until later in March
also discussed shipping [no problem]
perhaps a little more discussion this weekend...?
I have another problem with the Owon scope it has pulsed noise on lower sensitivity, looks like switched supply noise, maybe some caps drying out.
So back to using the hantek.
So tonight i re did all the tests but this time at 100khz intervals.
This time i used the 2 Chanel's to match the current and voltage phases, and once that alignment was done, i then used just 1 channel to get each value to reduce any chance of a second Chanel causing inaccuracy's.
I also used the pk-pk voltage, all measurements were take with respect to the Sig gen ground, so i had to subtract LCv from the Current waveform to isolate just current, i converted pk-pk to amplitude (/2) i then multiplied by 0.7071 to get Rms and worked my Pin, Pout & COP from there.
I employed the use of a spread sheet to do all the maths :)
Load=516 Ohm
NIR=10 Ohm
The only problem i can see here is that because i am only using 1 probe to measure each parameter i am hoping that the phase did not shift when i removed the 2 back to back probes during inital phase alignment.
I'm still getting high value COPs are they too good to be true.
Something i am unable to get my head round, i must be dissipating energy in my NIR
If i take 400KHz for example then my voltage across NIR 10 Ohm is 3.27-1.96 = 1.31/2 =0.655 * 0.7071 =0.4631505 Vrms
P=V^2/R P=21.45mW
So if i have this correct and i am dissipating 21.45mW in my NIR then how can i have a Pout of 31.48mW & a Pin of 32mW?
Something is very wrong here somewhere :D
The subtraction that means you get just the voltage across the LC and not across R means that your input power calculation V*I does not include the power dissipated in R. If you are doing anything different to that with your subtraction then please let us know.
Those high COP values seem good to me when you consider your transformer is unusual in having bucking coils. And you have many more parameters to look at in fine detail like optimum load, optimum turns and turns ratio, wire gauge, litz wire and so on. Not to mention waving a PM around near the core (but don't do that yet, we don't want the core to get any magnetization that changes everything for ever). If any of those yield COP improvements it bodes well for going OU.
Smudge
QuoteThe subtraction that means you get just the voltage across the LC and not across R means that your input power calculation V*I does not include the power dissipated in R. If you are doing anything different to that with your subtraction then please let us know.
I am measuring the pk-pk waveform across the LC and then measuring the pk-pk waveform across LCR and then subtracting LC from LCR to get just NIR waveform pk-pk value.
The waveform across LCR is the same as measuring the waveform across the Sig Gen.
I then make sure i have the Amplitude or pk-pk/2 and then multiplying by 0.7071 to get my Rms value for current and voltage, i then multiply the LCVrms * Irms to get Pin
It did not like a 10 Ohm Load
Peter,
Now that you are using a larger value NIR for your current monitor why not use this as the load and forget about transformer action. Just use the device as a pair of bucking coils. Then you don't need the subtraction. Your voltage across the NIR indicates the output power (dissipated in the NIR) while your voltage across the series LCR indicates the input power. Since the current is the same the ratio of those two voltages is the COP. It would be obvious if the L was creating some negative resistance because the input voltage (across LCR) would then be smaller than the output voltage (across R).
Smudge
Hi Smudge
Just trying to clarify see diagram.
It certainly would save a lot of measuring and time.
Thanks
Peter
PS sorry about drawing it upside down, short of time right now O0
Hi Peter,
That looks OK even though it is upside down. Hope it doesn't give you upside down waveforms ;)
Smudge
LOL O0
Not had much time last couple of days but have week off work next week O0
I keep hovering over the buy button on this scope, It's a bit cheaper in Germany but sill have VAT @ 20% Grrrr
http://www.rigol-uk.co.uk/Rigol-DS1074Z-S-Digital-Oscilloscope-p/ds1074z-s.htm
Well i finally found the courage to press the buy button so i now have a nice 4 channel scope on the way and it has 2 * 25MHz dds multi function generators built in as well ???
The Scope works well :)
Yellow=LCR
Cyan=LC
Purple=L
Problem is that at resonance LC is virtually zero and whats left is adjusted to be in phase with LCR and because of this i fail to see how the voltage across R will ever be larger than LCR or Sig gen.
What am i doing wrong?
R=516 Ohms.
The Sig gen is a DDS built into the scope O0
Peter,
You are not doing anything wrong, you would expect the voltage across R to be almost equal to that across LCR or sig gen. But if LC has some induced negative R then the voltage across R will slightly exceed that applied across LCR, and that is what you are looking for. But don't expect it to appear without some trial and error work. What you should do is find the conditions that maximises the voltage across R for a given input across LCR which you do by calculating COP each time. When you get to the optimum COP near unity then you can estimate the losses in L, C and coil R to see whether there is any real OU present. If so you look towards reducing those losses to see if you can get COP>1. If that proves impossible there is still the possibility of deliberately increasing the time delay through the core by adding intermediate coils and capacitors to create something approaching a lumped constant a magnetic delay line.
Smudge
Hi Smudge
Thanks for clarifying things, i could do with a resistance box to switch different NIR values in place but instead i will use a 25 turn 5K pot, each time turning to a LCR measured value, should be easier than having a bunch of odd value resistors loose on the bench.
Does not look as if i can get 700KHz working, same problem as before, Inductor capacitance, thus with a really small value C it's hard to adjust it.
Cheers
Peter
Wow that was easy, set the pot in 100 Ohm steps from 100R to 2000R took a scope shot each time.
This is for 600KHz will process the data and append when i get a chance.
yellow=LCR, Cyan=LC, Purple=L, Blue=Yellow-Cyan or LCR-LC=R
I did get a bit of drift on the pot which was not ideal and it varied, could do with precision resistors really :-\
EDIT OK uploaded spreadsheet with COP & data Table
> If that proves impossible there is still the possibility of deliberately increasing the time delay through the core by adding intermediate coils and capacitors to create something approaching a lumped constant a magnetic delay line.
Smudge
Hi Smudge,
Yes, actually when I first saw this thread, I thought it was going to be a discussion of using these capacitance- loaded shorted coils. These coils would actually make the device a magneto-electric delay line as shown in your paper. I encourage you and Peterae to try this at some point-- I have a hunch. There are several types of negative resistance, and this type with the coils bucking the input flux but with a delay, has an element of partial superposition that hints of overunity to me.
Smudge, when you refer to negative resistance in the thread title, are you referring to NR in the 1st and 3rd quadrants, or in the 2nd and 4th 'active power' quadrants? There are plenty of delay devices in all realms which get NR in the 1st and 3rd.
Such a device does not need to consume power, as you no doubt know, but also does not deliver excess power, as you hope to do.
There is some confusion about this matter in free energy discussions. I'm going to be talking about the seemingly conventional 1st and 3rd quadrant in my adiabatic thread, so I would like clarify things a bit.. if that hasn't been done already, somewhere that I missed.
orthofield
Quote from: orthofield on 2015.03.09, 14:32:33
Smudge, when you refer to negative resistance in the thread title, are you referring to NR in the 1st and 3rd quadrants, or in the 2nd and 4th 'active power' quadrants? There are plenty of delay devices in all realms which get NR in the 1st and 3rd.
Such a device does not need to consume power, as you no doubt know, but also does not deliver excess power, as you hope to do.
There is some confusion about this matter in free energy discussions. I'm going to be talking about the seemingly conventional 1st and 3rd quadrant in my adiabatic thread, so I would like clarify things a bit.. if that hasn't been done already, somewhere that I missed.
orthofield
I am talking about true negative resistance whose VI slope passes through the origin hence it exists in 2nd and 4th quadrants. I think the question "where does the energy come from?" is answered when you consider a very fast pulse. Initially electrical energy is converted into magnetic energy within the core halves before the wavefronts from the two coils overlap. The high mu of the material ensures that the aligned atomic dipoles supply considerably more energy to the air space between atoms than you actually put in. When the wavefronts overlap you get cancellation and that excess energy has to go somewhere. As in standing waves caused by waves moving in opposite directions the magnetic energy lost where there is a magnetic null appears as electric energy at the electric peak. So it seems reasonable that we should see some electrical energy returned from that otherwise hidden energy in the air space within the core.
Smudge
I have always suspected there was a shorted turn in the TPU's for 2 reasons, the open TPU looks like it has a shorted turn at the end of each visible winding and also electrostatic speakers were mentioned as a possible cue for SM finding the effect he needed to get the devices working and when i investigated the circuit for the electrostatic speakers there were shorted turn delays built into the speaker system.
When winding 1 shorted turn on the core, there is very little change, i can still achieve resonance and get near unity, i will run the tests i did before at 600KHz and vary the resistance and post the data for comparison, although in the last test it looks like my phase drifted off a little.
Peter,
Been looking at your recent 600KHz results. I have calculated the (low value) input resistance of the series L and C (at resonance) and it is about 44 ohms. It jumps about a bit, see the attached chart. I think it can be assumed that this loss resistance is mostly in the L and not in the C, and is a combination of coil and core losses. I have looked back to see what your bucking L is and I can't find a result. I found your primary bucking L as 15uH, and assuming a 6T primary and a 36T secondary I calculate your bucking secondaries to be about 540uH. Perhaps you can confirm this and that you were using the 36T bucking secondaries in your measurements. If so you might find this interesting.
At 600KHz the 3C90 complex mu data has us' of about 2500 and us" of about 150. The sub s indicates series values (parallel values are different) and it is the effective series loss resistance that we are interested in. The us' determines series inductance and the us" determines series loss resistance. At 600KHz the reactance of a 540uH inductor is 2035 ohms. To get the series loss resistor representing core losses you have to divide that reactance by us' and multiply it by us". So the expected value is 122 ohms. When compared to the measured value of 44 ohms that could indicate the presence of some induced negative resistance. But this is all rather tentative at this stage.
Edit. Darnation, forgot to add the image.
Smudge
Hi Smudge
Data is here for the 32Turns but i cannot remember if i posted the bucking details, i will re test this tomorrow.
LCR Test @ 10KHz
L = 4.366mH
Z = 274.41 Ohm
R = 0.785 Ohm
Q = 35
http://www.overunityresearch.com/index.php?topic=2773.msg45915#msg45915
Innacuracies in the data does not surprise me, i am getting load resistor drift and phase shift drift.
The bucking config parameters are
LCR@10KHz
380uh
R=0.32 Ohms
Q=74.5
Z=23.93 Ohms
OK results for 500 KHz
I will process the data and add that later, there's a lot of noise across the LC, i guess this is because such a low value cap is used, i have a 20-500pf variable cap in my cap box, all switchable caps are off and am using the variable to bring into resonance, i am also using flying leads to the cap box.
Again i was getting load resistance pot drifting.
Each scope shot represents a 100 Ohm increase, i went upto 1K5 this time hence scope shot 15
EDIT added the data, quiet interesting as the cop falls off and comes back.
Now that's interesting, scope shot 2 shows lots of high frequency noise, periodically as i am testing loads of noise appears across the LC, looks like i captured it in shot 2, it's sporadic, and appears maybe ,mains born noise as i am 100 foot down the end of an extension lead at the moment.
OK, that still calculates at a series loss resistance of 97 ohms so there might be something there. The expected series R core loss against frequency should be something like the chart here, calculated from the published 3C90 data. If the bucking plus magnetic delay is producing anything that smooth rising curve would show a negative going lump on it so perhaps that is what to look for.
Smudge
Edit. Darn forgot the chart again.
Peter,
Those latest results show the loss R in series with LC is 27 ohms. There is little point in doing many different load R values since the COP's you get are all associated with that fixed 27 ohm internal loss. It would be far more beneficial to stick with one load R and do different frequencies, then plot the loss R against frequency. We are looking for an inflection in that curve to indicate an anomalous effect. The loss R is simply the LC voltage divided by the current.
Smudge
OK can do that tomorrow, any preference on frequency sampling spacing, is 100KHz OK
and what fixed load resistance is best for me to stick with.
100KHz spacing OK to start with, starting at 100KHz then see what happens as you go up to 500KHz. 100 ohms for the load.
Smudge
OK did 10KHz spacing in the end, started at 100KHZ & finished at 800KHz, as there are over 60 shots i have zipped them, i will process the data and append to this post once done.
EDIT Added spreadsheet with data
PS i now calculate LC Resistance in the spread sheet
Hi Peter,
That's an impressive set of results, well done. I have plotted the loss R of the LC and it shows no sign of the wanted effect :'( . It is a straight line on a log-linear plot, see image Loss R.bmp.
I guess the next step is to introduce some deliberate magnetic delay between the two coils and see what effect this has. My suggestion for the magnetic delay is to create a magnetic delay line by winding a series of coils and connect them with capacitors, as shown in the attached images. The first one shows a balanced delay line that would be classical but for the fact that the input and output are magnetically coupled. The core is shown as rectangular with input and output coils at each end. The delay region would have the end capacitors at one half the value of all the other ones. This needs transposing to the circular core you use. The second image shows the top and bottom winding directions with the capacitor cross connections in simplified form. In the limit you could use single turn coils and lots of capacitors. Start with small value capacitors, use one of your coils as an input and the other diametrically opposite as an output and see what delay you get. With some significant delay it would then be interesting to try the bucking coil arrangement and see how it differs from those present results.
Smudge
Hi Smudge
Thanks, I'm away for a course 2 days and am revising at the moment, so not much will happen now until the weekend O0
I did try again to see a delay between one coil and the other as the new scope does phase angle, but it was still inconclusive and did not really see a movement in phase so this next setup will be interesting if we can indeed introduce the phase delay big enough to be measured O0
Cheers
Peter
Hi Smudge
Got any ideas for values of cap to try, shall i do single wire turns or a few turns per winding and how many windings, we might as well try for a significant delay to make it obvious, i am trying to plan the work i will do over the weekend, easier for me if you put a proposal to me as opposed to me trying random values that may not work out.
PS maybe you have a ball park inductance for each coil with a cap value that can be calculated for an expected delay result.
Cheers
Peter
Quote from: Peterae on 2015.03.19, 19:24:35
Hi Smudge
Got any ideas for values of cap to try, shall i do single wire turns or a few turns per winding and how many windings, we might as well try for a significant delay to make it obvious, i am trying to plan the work i will do over the weekend, easier for me if you put a proposal to me as opposed to me trying random values that may not work out.
PS maybe you have a ball park inductance for each coil with a cap value that can be calculated for an expected delay result.
Cheers
Peter
If you aim for say 1 uS per section and you had 10 across the top and 10 across the bottom you would get a 10uS delay. For that 1 uS you need for each section
1 turn and 0.2355 uF
2 turns and 0.0589 uF
3 turns and 0.0262 uF
Take your pick.
Smudge
Just to get everyone's brain working overtime, here is another suggestion for a different form of delay transformer.
Smudge
Thanks Smudge that will save me a lot of time.
PS if you find a cheap ring core on farnell, i can order a quantity to try to build the device in your new PDF for a delay transformer.
The one with the high K ring, we could use a ring containing pure water, pure water can have a K of 80 @ 20 Deg C, i have a RO machine for pure water, just need to find something to contain it in a ring, if a hose was used then we could make the high K ring quiet large in diameter, just join the 2 ends together and fill it with water.
While searching for an old paper of mine I discovered some more on magnetic delay which might be of interest.
Smudge
Hi Smudge,
Thanks for sending those papers you turned up. The 'lumped constant' one has the test I remembered, and it's good to see it again.
orthofield
From Peter
QuoteThe one with the high K ring, we could use a ring containing pure water, pure water can have a K of 80 @ 20 Deg C, i have a RO machine for pure water, just need to find something to contain it in a ring, if a hose was used then we could make the high K ring quiet large in diameter, just join the 2 ends together and fill it with water.
An elongated pseudo ring might work with 2 long rods of high K ceramic material.
For a "K" in the thousands you could cast two Barium Titanate rods and fire them in a kiln. First you would mix into a slurry using water, then squeeze it in a cylinder former with a press, driving out most of the water. After ejection from the cylinder former, they would be fired in a kiln to promote crystal growth.
After firing, the rod ends would be sputtered with copper for soldering or a silver epoxy could be used. The ferrites would be slipped over the rods, after which the connecting wires with drive ferrites would be applied.
This is an abbreviated method of high voltage ceramic capacitor construction. More here:
http://www.scielo.org.ar/pdf/laar/v35n1/v35n1a05
Sounds good ION, not quiet got all the equipment to do this yet, but have the vacuum pump.
If i ever get enough time a kiln would be a great addition and also a sputtering chamber O0
Quote from: Peterae on 2015.03.21, 07:38:57
Sounds good ION, not quiet got all the equipment to do this yet, but have the vacuum pump.
If i ever get enough time a kiln would be a great addition and also a sputtering chamber O0
See if Smudge approves, I don't want to modify his original sketch if he has some reason why it might not work with rods.
Barium Titanate rods may be available commercially. Also consider that certain very high resistance ferrite rods might work as capacitors, you would only need to make the ends conductive and you might be able to dispense with many of the ring ferrites as they would be inherent in the rod design.
Hi folks,
I believe the rod is a better structure for both the domain delay line, and any capacitance that is coupled to it.
There's something just not right about the toroid structure to me.
Consider a toroid with a single pulse coil.
The cone shaped domain wall nucleates in the center of the coil and then expands in both directions through the core. There are two domain walls expanding in opposite directions. Each domain wall as it moves away from the nucleating coil will have *the same inverted conical shape*, with the points of both cones aiming at the center of the coil.
The divergence of these walls creates a rapidly diminishing diamond shaped region of remaining random flux on the opposite side of the toroid. But it appears to me that the two domain walls are somewhat 'solitonic', and to preserve both the energy stored in the domain wall rotation process, and the forward momentum, they will pass through each other at that point--??
Smudge has pointed out that surface waves travel at right angles to the iron, and in a toroid these begin at the coil and expand through the central and surrounding spaces. These waves could be synchronized with the magnetization wave inside the toroid, or could be at C, or could be instantaneous-- I don't know. According to the thesis from the naval student I sent a while back, on a toroid the surface waves arise from the coil surface and then travel at right angles to the toroid, until they merge on the other side.
I agree that Smudge should weigh in on the nature of the capacitive loading used.
High-resistance (low-loss) ferrites have a electrically controllable permeability. See attached patent, which I mentioned to Smudge a while back but couldn't find. So cleaning the ends of the ferrite rod, then soldering some leads to it, should allow reasonable amount of control of mu, but you would need a DC HV generator. The attached patent shows how to do this, although it doesn't show the voltages needed. Probably pretty high.
BaTi rods may not be available since their functions have been taken over by even higher k perovskites like LZT, but any of these should work. Long rods are not made, AFAIK. The attached datasheet for an electrostrictive sonar transducer rod is probably as good as it gets, but haven't found any LZT rod like this available on a 'buy one' basis. It would be an expensive way to go. I think the Cyril mentioned soaking the delay line in a liquid dielectric, and this seems a lot easier if Smudge's multiple shunted capacitor method doesn't work out.
Those Perovskite rods can be used for acoustic overunity devices as Wooten MRA, Hutchison's '5 Watt generator', Davidson's magneto- acoustic generator, plus various nonreciprocal transducer designs, plus ambient thermodielectric generators with high output, plus detectors of the Earth's diurnal gravitomagnetic fluctuations, etc. -- So, always a good thing to have around :-)
orthofield
Hi Smudge
I built the delay as per your toroid diagram above 157.
I used 6 off 220nF caps with each 1 turn of thick gauge wire, so we have 5 turns each side
It appears to be very frequency dependant.
I tested at 600KHz & 500KHz , at 300KHz i was having trouble seeing a delay, i think there was one but it was impossible to measure.
At 600KHz we had 139 Degrees of shift with a time period shift of 644nS
At 500KHz we had 84 Degrees of shift with a time period shift of 464nS
EDIT just to explain the set up
My sig gen is across the Yellow scope probe and across one end inductor
My blue scope probe is across inductor at other end of the toroid
Wow, those are huge phase shifts. Can you please try a few things. First disconnect all the capacitors and check that the phase shift is zero and not 180 degrees (easy to get one of the coil connections the wrong way round). That establishes the starting base line. Then reconnect but now put a 50 ohm load onto the output (I assume your sig gen is 50 ohms, if not use the sig gen value). An open circuit delay line will have weird phase effects at different frequencies so we need to isolate them from the true delay, and that may be why your 300KHz result was so different. You could also try a pulse input. I see there is a voltage attenuation which is to be expected so don't expect the pulse shape to be preserved. You are treading new ground here with this deliberate phase or time delay within a transformer core, so may I suggest you keep reasonable notes on your experiments.
An alternative approach may be to start with all capacitors disconnected and a pulse input. Then add small value capacitors, like 10 pF and note the effect. Continue gradually increasing the capacitor values, and the trends that occur should tell us a lot about what is going on.
Smudge
Hi Smudge
As it was disconnected after the test and reconnected for bucking mode, i cannot be sure which way i had the probes connected in the above test, to be sure in the future i have marked + & - on each winding, anyway i am doing what you suggest in your post.
So i connected the caps back up after verifying the polarity of each coil, and it is still variable dependent on the frequency, there is a frequency @ 750KHz where input is in phase with output, if i go higher in frequency the input phase leads, but if i go lower in frequency the output phase leads :o
Anyway i will continue with your post above.
QuoteThen reconnect but now put a 50 ohm load onto the output
When you say output do you mean the sig gen output or the output coil, i will try both, and yes my signal gen is switchable 50 Ohm or high impedance and was set to high impedance during all previous tests (only just found this setting in the internal help screen), i have now switched to 50 Ohm.
Pulse mode at 10% duty 100KHz, yellow across sig gen & coil, cyan across other end inductor
Shot 93 = no 50 Ohm resistor
94=50 Ohm across sig get & coil
95=50 Ohm across load coil
EDIT just been rereading your posts above and noticed this
QuoteThe delay region would have the end capacitors at one half the value of all the other ones.
So it looks like my end caps need to be half my mid caps value, as i have been using 220nF then i will try some 100nF at each end, is that right?
I silvered the ends of a number of ferrite rods of unknown material type. These were removed from old radios. The capacitance was negligible, just a few picofarads.
I have a U shaped ferrite core (normally also called a C) from some switching magnetic structure like a HV flyback core.
To my surprise with the ends (mating faces) silvered, it read 1500 pF.
For what it's worth.
Hi Smudge, all,
I found this patent while looking for something else. It is a bit of an outlier to the present discussion, but might provoke some thought.
It talks about "magneto-electric induction" , the inverse of electro-magnetic induction, where a dielectric wire is wound around a ferrite core. Putting an electric field through the wire from a HV source creates a magnetic flux in the ferrite. The inventor, at Bell Labs, claims that the symmetry of Maxwell's equations say it makes no difference if the magnetic field in the toroid comes from a real current, or a displacement current. This seems odd to me because it implies you could use a very high impedance, high frequency source (like some Tesla coils) into a dielectric 'wire' around the core to create an oscillating magnetic field in the core. What happens when another, copper, coil is put around this, and the magnetic field is tapped for power? Does the Tesla coil experience a load proportional to the loaded coil?
orthofield
Hi Ion,
Thanks for checking out the bulk C of the different ferrite forms. It obviously can vary a lot and the more modern the material, and thus the less conductivity, the better.
I'd just been reading in the patent I sent about how it was hard to make measurements of dielectric constant when the materials were high-k, because the quality of the electrode contact with the material becomes a major factor... so silvering was the ideal contact method, really :-)
If you've got an LC meter you're in a perfect position to check for the effect on the mu of your ferrite U core by first measuring L of a coil around it, then 'charging' the ferrite like a capacitor through the silvered regions, and then remeasuring the L. The ferrite can be considered to be a somewhat leaky capacitor, I think, so some of the capacitor energy should even be recoverable. As discussed in the Desguerra patent, (and another patent I haven't found again yet) there should be an effect of perhaps 10% change in mu due to electric field with your U core. As mentioned, the patent doesn't give numbers on the E-field used, but I'd guess it was pretty high, but hopefully no more than 100 V or so..if you don't see an effect with 100 V or so, I wouldn't bother going higher...
Having a transducer like this, where the ferrite mu can be varied electrically, gives us easy reactive amplification of currents without having to worry about any real impact on the voltage source. Whether this is useful just depends on how big the effect is, in a really high quality core.
Most of the experiments on this sort of thing I've seen involve core *currents* through amorphous metal strip, rather than ferrites. There, very small currents can change the mu of the material dramatically. This effect is enhanced even more when the strip is twisted. I've proposed ou designs based on reactive amplification using a twisted strip of metglas ribbon--which should have hugely nonlinear reactions to small currents-- but nobody has ever taken me up on it :-)
orthofield
Good find Ortho. The link between electric and magnetic effects is well covered in EM theory and the inventor is quite right. You can wind the electric circuit around the magnetic core or you can wind the magnetic circuit around an electric core. Displacement current creates a magnetic field. I once invented a transformer that consisted of a parallel plate capaciitor in the form of a circular disc of dielectric placed within a circular ring of ferromagnetic material. The capacitor was in effect part of a single turn. To get the equivalent of a step up or step down ratio the capacitor was divided into two by having separated electrodes on the flat surfaces of the dielectric. So in effect there were two turns, each with its own capacitor, one turn being the primary and the other the secondary. Equal capacitances gave 1:1 ratio. Unequal capacitances gave step up or step down. For symmetry the electrodes were concentric. It was a transformer that primarily gave you a current ratio, not a voltage ratio. But of course only worked at high frequencies. Never did take a patent. And you can get the equivalent by shifting separate capacitors along the wire so they are not then within the core, you then have a conventional 1:1 transformer with different value series capacitors in primary and secondary and that too acts like a current transformer.
Smudge
Quote from: orthofield on 2015.03.22, 15:29:35
If you've got an LC meter you're in a perfect position to check for the effect on the mu of your ferrite U core by first measuring L of a coil around it, then 'charging' the ferrite like a capacitor through the silvered regions, and then remeasuring the L.
But to do this you really need a closed magnetic circuit. Any air gap (a single U core has an enormous air gap) and the inductance is not much effected by change of mu in the ferrite. If you don't have the other U or I core then you need some other material to close the circuit.
Smudge
Hmm, yes, quite right Smudge.
orthofield
But to do this you really need a closed magnetic circuit. Any air gap (a single U core has an enormous air gap) and the inductance is not much effected by change of mu in the ferrite. If you don't have the other U or I core then you need some other material to close the circuit.
Smudge
[/quote]
Peter,
I did mean 50 ohms across the output and your scope shot 95 looks better than the others, the output is more pulse like. With a quick eyeball, taking the 50% point on the output, it looks like you have about a 1.5 uS delay there. With such a small number of segments those waveforms don't surprise me, I am sure you would get better pulse shape with more.
Your 750KHz phase measurement indicates a full wavelength shift of 1.33 uS that agrees with that 1.5 uS eyeball. At half that frequency you should see your output waveform inverted, a 180 degree phase shift. When you realize that you then have a transformer that is still working as a transformer (albeit a poor one) but the flux is not continuous around the core you know you are doing something the text books would say is impossible.
For the bucking coils work we want a 90 degree phase shift, so maybe you could do a quick look-see at the bucking arrangement using a frequency of 187.5KHz and see what happens.
Smudge
Ortho,
If I may make a suggestion, when you click the Quote" button you get the message ready for you to type your reply. You then seem to delete part of the message that includes the httm quote signal (the word "quote" in square brackets) that the mark up language uses to recognize the quotation You leave the [/quote] that signals the end of the quotation. This probably comes about because you type your reply at the beginning of the quote and that knocks off the httm marker. Try typing your message after the [/quote] marker.
Smudge
This is with no 80 Ohm termination resistor.
so we have 4 shots 0 Degrees @ 757KHz, 270 Degrees @ 509KHz, 180 Degrees @ 314KHz ish and 90 Degrees @ 102.5KHz which is quiet hard to get as the phase moves quiet fast around here with small change in frequency.
PS before your first post today, i captured all the data from 100KHz to 1MHz with this delay setup. i will post the data as i process it below and add a zip file with all the scope shots some 80 odd shots
So does my first & last cap need to be half my other caps, so 100nF for the 1st & 2nd and 220nf for the rest
OK added bucking delayed zip which holds all the snaps with the delay line config.
OK now added data
Peter,
With regard to the first and last caps they should be half the value of the others but with such a crude delay line you will probably find it makes little difference. Will respond later when I have looked at your latest bucking data.
Smudge
Here are your bucking coil results plus the LCR-R (loss R) result from your previous work without the delay. There is no sign of the expected dip in the loss unless it occurs at a lower frequency. It might be worth going somewhat lower to see but I suspect that both loss R curves will tend to meet the zero frequency axis at the same point. I was expecting a clear dip in loss R (but not going negative at this stage, that would be too much to expect).
Smudge
Hi Smudge,
Thanks for the tip. Ion mentioned this to me before but I didn't quite get it, and continued to delete the tag.
orthofield
Hi Smudge
Well it's good we are doing the practical stuff, so whats my next move.
Could it make a difference if the delay coils are wound in the opposite direction to the bucking coils direction, i have not checked but maybe my bucking coils are clockwise and the delay coils are anti clockwise.
Maybe i need to make a better delay with more turns.
I wonder if we should try a higher value load maybe 500 Ohm.
Quote from: Peterae on 2015.03.23, 17:53:30
Hi Smudge
Well it's good we are doing the practical stuff, so whats my next move.
Could it make a difference if the delay coils are wound in the opposite direction to the bucking coils direction, i have not checked but maybe my bucking coils are clockwise and the delay coils are anti clockwise.
Well your bucking coils are wound (or connected) in opposite chirality so you can't claim them to both be clockwise. Changing the winding direction of the delay coils will not have any effect. Well it would have an effect if the top half were reversed and not the bottom half, you might care to try this but I think it will screw everything up.
QuoteMaybe i need to make a better delay with more turns.
I wouldn't try to go for greater delay (more turns between capacitors) but I would look at say using two turns per section and reducing the capacitance values by a factor of four. That should keep the time delay the same. Maybe better still is to increase the number of sections so double the total number of turns, keep to one capacitor per turn but use lower capacitor values so that the total capacitance (the sum of all) remains the same. This might give you a better delay line with less dispersion.
QuoteI wonder if we should try a higher value load maybe 500 Ohm.
I don't think this will help since the loss R (your LCR-R) won't change and that is what I am concentrating on.
If this bucking thingy doesn't lead anywhere take pride in the fact that you are probably the only person in the world looking at a transformer with deliberate magnetic domain time delay between primary and secondary O0 . And there is more to do looking into the possibility that in a (non bucking) transformer of this type a reactive load like a capacitor can reflect as a negative resistance at the input. You are now expert at measuring input resistance over a wide frequency range 8).
Smudge