Bucking toroid Back emf


Bucking toroid Back emf
«  »Last edited
There is something interesting going on here. This is inspired by Matt Watts.
Quick info: pulse generated is almost not loaded down (no current draw), but a 450V resonant wave is generated from this pulse.

I have a toroid with 2x 150cm wire wound in bucking mode (counter wound so the magnetic field is opposite).

The IGBT puts 12Vdc on the coils, and switches this, at the resonant frequency of the second bifilar coil.
when the power is on the coils, the magnetic fields "cancel out" but, the energy is still there. I see it as if the ether is being compressed.
When the switch is opened the ether decompresses quickly. giving a bemf pulse.

That pulse is taken at the switched side from the bucking coil into the outside rim connection of a phi ratio hole speaker wire side by side Bifilar coil. the inside rim connection is left open

The bucking coils, give a inductance of 0,06mH that is very low... This is a perfect match for power transfer into a bifilar coil (low impedance).

The resonant coil is a similar coil, placed on top. the center is grounded, and the outside rim is probed, showing a 450V pp @ 499kHz.

It takes some power to let the field buck in the coils. But the pulse that comes out, almost isnt influenced by the bifilar coil. The 105V pulse drops to 95V when both coils are in position.

I wonder how many coils I could put into their resonant frequency, with that b'emf pulse from the bucking coils.
I have to test how much energy is needed to make that pulse. I guess its a bit more than I would like, because the coils are bucking. Its like putting two magnets that are rejecting each other, are pushing together (in the toroid).

also... I think the material of the toroid isn't optimized for this. I need to wind a better toroid core.
Using a 12V battery as power source for the igbt/bucking
and the rectified sine into a cap, via a small load (led light) back into the battery, would be... wonderful.
Even the left over Bemf pulse could be rectified, buffered in a (low esr) capacitor, and put back into the battery.

Sorry For The Long Story... I understand this will be much more interesting with a closed loop result (charging battery and bright LED). :yodel:

And :ttiwwop:
indeed, pictures will follow. my phone is charging, and I need a recharge too.

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Matt Watts

Re: Bucking toroid Bemf single wire transmission
« Reply #1,  »Last edited
Here's the schematic I used in my testing.  May have had the CSR on the other side of the ground leg--can't remember for sure.

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Re: Bucking toroid Bemf single wire transmission
« Reply #2,  »
tnx for the schematic Matt,
I cant replicate because of the double switch.
The relais isnt fast enough either.

to do this I also would need a proper double signal generator.

Dear Universe. please provide me with the matarials needed to succeed. Thank you.
Re: Bucking toroid Bemf single wire transmission
« Reply #3,  »
Pfew. I had one proper ring toroid core, that I used for the hairpin pulses and for nelson rocha's published circuit.

now its rewound into a bucking coil. lets see if this works better.

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Re: Bucking toroid Back emf
« Reply #4,  »
i posted the results at my nelson rochas devices thread. a single switched bucking coil doesnt give the right results.

so a double switched bucking coil might do the trick.
 but... in the drawing the bifilar coil stays connected to the bucking coil.
this makes it a closed loop.
Steinmetz states that a magnetic field in a closed loop doensnt need a external source to exist. (just as a open looped capacitor holds its charge in the dielectric field).

the bucking coil when stressed, will release its unnatural field energy, or wont it? because its also in the closed loop!

If it releases its energy into the bifilar coil as a b emf, then the magnetic field of the bifilar coil will amplify. because its in a closed loop! this is a magnetic field storage device (if it works).

so to transfer the energy into the resonant coil, the loop will need to be opened, to create a back emf from the bifilars magnetic field...

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magnetic current, a bucking coil in a closed loop
« Reply #5,  »
if there is such a thing as a magnetic current keeping the magnetic field active in a closed loop inductor (bifilar coil),

would the bucking coil present itself as a open circuit to the magnetic current? because its like 2 opposing magnets
 resisting eachother?

mighty interesting this!
Re: Bucking toroid Back emf
« Reply #6,  »
hmm I might see what happens with my relais. the frequency wouldnt give a voltage from resonance, but it would show if the pulse is transferred
Re: Bucking toroid Back emf
« Reply #7,  »
this time i pulsed the relais at 400 hz 85% duty cycle.

I connected the center coil of the 3 stack bifilar coils. to the buckingcoil and the relais. the relais switches between the power supply (2V 1A) and the coils.

the magnetic fields showed up, but didnt stay.

the pulse on and pulse of shows a big spike on the scope.
the top and bottom coils also show the spikes, so the energy is transferred

all good signs.

the goal stays the same. use the high voltag bemf to get the coil into resonance, a higher voltage is needed. this will need to come from a higher current into the bucking coil, giving a higher b emf pulse, giving a higher voltage rise in the resonant coil.

Lets see what Matt can do with his switches

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Re: Bucking toroid Back emf
« Reply #8,  »
these bucking coils feel so unnatural. like trying to stick two repulsing magnets together. its unnatural and takes alot of energy.

what if we do it differnly?
only pulse one half of the bucking coil, and use the whole coil as output.

the half coil would build up a field im the torroid, without much effort just a basic inductor.

but the B emf is captured by the bucking coil with its low inductance/impedance.

that way we can capture and transfer the energy into a bifilar coil.

combining the low power high volts of the back emf, and the low impdance  of the bucking coil.

this makes alot more sense to me. man sometimes i really feel smart :cool:
but then... it also needs to work :hide:

we could even use the whole bucking coil as a normal coil if we connect it right. just use some diodes to direct the current and the back emf (maybe)
Re: Bucking toroid Back emf
« Reply #9,  »
I've played with the concept.
only using a bucking coil and only pulsing one half wasn't great.

so then I wound a extra coil over one half. chris sikes hyiq.org is where this came from. He states the windings between the coils should be 1:3 (3 is the bucking coil).

this seems to work. But to get a good peak I needed to get the frequency lower. aroind 60 khz. then the spikes went up skyhigh, if i got even lower, I could hear the coils hiss from sparking over.... so.. this works.

It only works in those frequencies because at higher frequencies the system becomes resonant and the single high voltage spike turns into a resonant sine wave (on the bucking coil).

so ill keep it around 60khz, damn low for a resonant frequency of a bifilar coil. but with added caps it will tune down. and we dont have to tune down the pulsed bifilar so thats perfect.

now let's see what happens when i connect it to the bifilar coil
Re: Bucking toroid Back emf
« Reply #10,  »
when the bifilar is added, we also add capacitance, lowereing the resonant frequency of the coil and destroying the spikes, turning them into sine waves.

but there is still hope. maybe its time for some fast diodes to kill the resonance.

(or another wild idea i havent tried, what if we only pulse one winding of the bifilar coil)

Im pretty wasted.
diodes ...

Matt Watts

Re: Bucking toroid Back emf
« Reply #11,  »
Quote from evostars on July 10th, 2017, 03:16 PM
chris sikes hyiq.org is where this came from. He states the windings between the coils should be 1:3 (3 is the bucking coil).
From 1:3 up to 1:6.  Stan Meyer was 1:6.  Floyd Sweat I think was at 1:4.


Re: Bucking toroid Back emf
« Reply #12,  »
Quote from Matt Watts on July 10th, 2017, 04:19 PM
From 1:3 up to 1:6.  Stan Meyer was 1:6.  Floyd Sweat I think was at 1:4.
and the Bloch wall of the coils wasnt overlapped, and there needs to be a current in the bucking coil for it to work...

now at 60khz I get pretty big spikes when i ground the center of the bucking coil.
but what I dont get... is the spikes (600V or something) are inphase at both ends. so there goes my low inpedance output...
Re: Bucking toroid Back emf
« Reply #13,  »
tried diodes uf4007 in series and parallel.
no success.
Re: Bucking toroid Back emf
« Reply #14,  »
hmm I notice i didnt write everything down.

there was one experiment that was ineresting.

bucking coil center tap grounded.
primary coil wound over one side of the bucking coil. and pulsed.

the spikes on the outputs of the bucking coil where large, but in phase.
I thought I needed out of phase signals.

but To be sure I want to recreate it and connect a bifilar to see what happens.
I would think the equal pulses cancle each other out. but my thought have a tendancy to be wrong. maybe there is more going on.
Re: Bucking toroid Back emf
« Reply #15,  »
I took my big black torroid with bucking coil around it. total 3meters of wire.
I separated the two windings leaving two spaces open (like seen in nelsons vids) and fixed it with black tape.

then i wrapped tape around one if the bucking windings and rolled a 1m (1/3) around it. this single coil then is pulsed with my igbt at 806khz. 84% dutycycle.

the bucking coil is grounded in the center tap. I probed both endings of the bucking coil.

I noticed a difference in the signals.
the bucking coil part under the windings of the primary, showed the pulses.
but the other part of the bucking coil showed a resonant sine. I tuned it(by placing a 560pF cap parallel over that coil to lower the res freq) and got a  voltage rise of around 500V pp.
the sine was "out of focus" this most of the times relates to bad grounding, but i could not fix it in the regular ways this time.

so there is a kind of resonance going on with the ring torroid.

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Re: Bucking toroid Back emf
« Reply #16,  »
I used the diode trick again and charged the capacitors to 644vdc. 9.3uF
The middle of the caps was  connexted to ground. the other ends to the diodes, and to the single wire with the resonant sine.

the charge time was around 4 seconds.

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Re: Bucking toroid Back emf
« Reply #17,  »
I let it charge a while without dc meter.

I disconnected the power, and after that (voltage then drops) i measured 800V Dc in the caps...
Re: Bucking toroid Back emf
« Reply #18,  »
thats a lot of energy from a pulsed bucking coil.

maybe I should do the battery trick again.
run the igbt from the battery, and charge it with diodes
Re: Bucking toroid Back emf
« Reply #19,  »
nope the battery doesnt charge when it also powers the igbt. but still it drains slowly.

charging the battery up again works great with that recitfied resonant sine
Re: Bucking toroid Back emf
« Reply #20,  »
Its not bucking at all. its a single coil at resonance. nothing special.

I will need to go down in frequency again, to that 60khz and get the spikes again.
Re: Bucking toroid Back emf
« Reply #21,  »
ok got the pulses again.
12v igbt pulsing the primary at 92kHz 90% duty cycle.

center of the bucking coil grounded, this basicly creates 2 coils.

bucking coils out puts are probed. the one is lower in voltage around 375V  due to the ringing.
the other is spiking around 550V pulses.
 the pulses are in phase.

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Re: Bucking toroid Back emf
« Reply #22,  »
hooked up the 3 stacked bifilar coils.
used the center coil as resonant coil and probed it. It showed a 225V peak with res sine behind it. I would need a cap to tune into this res frequency of 90 khz.

the outside top bottom coils where hooked up with 180 phase opposite, series connected (outside rim of top coil to inside rim of bottom coil).
this way the out of phase pulses add up in the middle again.

now lets see if i can tune the center coil down.

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Re: Bucking toroid Back emf
« Reply #23,  »
the more capacitance I use to tune down the bifilar coil, the less high the resomamt voltage rise is.
around 7nF gave a 166khz sine of 77V pp
3.3nF @ 235khz gave 85V pp

there is also no deviation of a compass needle. also a nice gimmick that nelson showed.

the way I'm doing this is what I have tried before with the opposite voltage pulses.
this is the same because i have the 2 series connected pulsed coils in opposite fase.

this way the low impedance of the ring torroid bucking coil is used with a relative low input power via the igbt pulsed coil (Igbt stays relativly cool.

So the trouble comes from the resonant frequency of the bucking coil. it needs to stay well below to give pure hV pulses.

on the other hand the bifilar coil needs a high enough resonant frequency to produce a decent voltage rise. (capacitance needs to be between the windings, not in the capacitor)

these two problems should be solved. so they match.

I now use 2 coils in counter phase and feed them with the bucking coil output pulses.
I could also use a single bifilar coil, if I rewire it into a bucking coil (reverse connections of one coil).

Re: Bucking toroid Back emf
« Reply #24,  »
I measured inductance of the series connected top and bottom bifilar coil.
seems I didn't use it in bucking mode as the inductance was relative higher then when i reversed...

so. it does work with a normal coil. amazing.
too tired to go on now.

will need to test again with the center coil pulsed.