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2018-12-10, 02:14:18
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Author Topic: Self running coil?  (Read 68787 times)
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Hi everyone,

I have a new effect involving a ferrite toroid coil which is being pulsed at a very specific frequency, duty cycle and uses a permanent magnet with an air gap.

It seems to be self running once started and the source battery can be disconnected and the capacitor will maintain its charge and in fact gain energy.

I found this effect over a week ago and since then in my spare time have been trying to find what I could be overlooking. So far I have not found anything, so I invite anyone to comment as to what I may of missed.

The video demo: http://www.youtube.com/watch?v=L0AZkovLTT8

If the magnet is removed there is no effect

If the magnet has no air gap there is no effect

If the frequency is changed there is no effect

If I leave the battery connected it does not drain in voltage and actually seems to be charging the battery.

I have changed the mosfet with the same IRF640 and it is the same. I tried it with IRF840 and it works but not quite as good as the IRF640

The effect only seems to work at low voltage 2.80vdc is about the highest I got it to go so far.

Please feel free to share you comments or concerns.

Luc
   

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Hi gotoluc,
    I didn't get what you were doing with the 1.5 volt battery?, what is it running and I guess I don't understand how you consider it to run itself when the big battery is still conected and powering the drive circuit? It would be really great to find something that can run itself.


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"Whatever our resources of primary energy may be in the future, we must, to be rational, obtain it without consumption of any material"  Nicola Tesla

"When bad men combine, the good must associate; else they will fall one by one, an unpitied sacrifice in a contemptible struggle."  Edmund Burke
   
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You do need to opto  isolate the 555 which is likely the source via the fet.

Nicely demonstarted well done .. I hope im wrong
   

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Hmmm Lets see,

2 coils facing each-other, Bias Magnetic field in the right place....This has Spherics's theory (tetra, etc) written all over it. :D

Great Job Luc!


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Where is the original video?
   
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Hi,
nice spike at power on i assume. what did SM say about OU and power on....mmmmmmmm
I hope its connected.
Cheers    Steve.
   

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Hi Luc

Good work as usual.
I would have thought you should have your Chan 2 of the scope on DC to measure current as a constant current drawn across the resistor will be a dc offset and this wont show on the AC setting.

There can be energy passed from the gate of the FET, i have seen switching waveforms on some of my tests with my source volts switched off, whether this is enough to cause your effect i am not sure.

Peter
   
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Hi all,

thanks for your interest.

Many of the posted concerns have been tested prior to starting this topic. However to satisfy these questions and doubts I made a new video as I know it is had to believe that you can pulse a coil and more energy seems to come back. It took me over a week of testing different things after I found this effect to try to find what I could be overlooking but came up with nothing yet.

Video: http://www.youtube.com/watch?v=ZvlsNZJQ3gQ

Luc
   
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Hi all,

another update.

I believe when the Toroids magnet and pulse Frequency perimeters are all set right the Toroid coil goes into Resonance. Since connecting my probe or bringing any ferromagnetic material close by the Toroid has a negative effect (becomes out of tune).

I tried collecting Flyback and it is possible, however when I do the math it all comes to the same. What I mean is, the flyback energy you collect is that much less going back to the source capacitor.

I made a new video to further explain the the importance of the Frequency, Duty Cycle and mostly the Permanent magnet that without it there is no Frequency I ever found that will create this effect.

If we think about it ::)...  I only remove the magnet from the toroid coil and it starts to use current, so how can the energy that was going back to the source of been coming from the MOSFET gate pulse and now suddenly stop???

New video: http://www.youtube.com/watch?v=7Fb5FOfme1g

I'll answer specific questions soon.

Luc
   
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@gotoluc

As usual nice videos and interesting results.

One of the things I discovered recently while working with all sort of LEDS and coils for making my five videos is that the volt meter or the scope probes can inject power in the circuit. To see if this is possible, just take the lowest voltage LED you have, preferable in the 1 volts range and just put your volt meter to it and see if it lights up. Then try your scope probe. I was amazed to see mine light up and this could explain what is going on.

Especially when doing works with low voltage/amperage.

Eventually, you may consider winding a nice bucking primary on your small toroid and do other tests with it. That's my next direction.

But keep on go'in man.

wattsup


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Hi,
 Another fine video.
 Addition of the magnet to the torus will change the characteristics of it. It loads the core material with 'magnetic flux' and this reduces the 'available flux' of the device.
If you have a winding on it then this extra loading will change the inductance of the coil. As the available flux density reduces so does the reactivity and if you measure the inductance with then without the magnet present you would find the values differ. More inductance lower applied field.
This will affect the resonant frequency too.
There are several types of core material.
Search saturable reactor on wiki for more...
Have you tried to remove the magnet slowly while tuning in on a lower freq to see if the magnet isn't required?

Cheers  Steve.
   
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Hi all,

Gyula has posted this explanation at the OU topic as the probable cause of the effect.

Hi Luc,

Thanks for your explanations in the second video.

Now my understanding on your circuit is that the MOSFET output capacitance (CDS and the 44.6mH toroidal coil forms a parallel resonant circuit at 18.8kHz.  How?
See the data sheet for your IRF640: http://www.irf.com/product-info/datasheets/data/irf640n.pdf

See Fig. 5 in Page 4, and the output capacitance curve, Coss, shows about 1500-1600pF at 1V drain-source voltage (taken at VGS=0V).
And if you calculate the C value from the 18.8kHz resonant frequency using  the 44.6mH toroid coil value, you get 1.61nF capacitor value! (I used this online calculator: http://www.whatcircuits.com/lc-resonance-frequency-calculator/ )

This explains why the distance of the magnets from the core is so precisely needed to adjust: you simply change and fine tune the toroidal inductance for the best value for getting the highest output voltage which can occur at the highest impedance a parallel LC circuit provides. No resonance=no max output. The drastic change in the output capacitance also explains why you find the "effect" works at no higher than 2.8V DC: the capacitance gets reduced under the 1000pF values and the LC circuit impedance becomes lower and lower. You seem to nicely finetune the output circuit for most favorable match of the components that ensures the highest possible output.

The battery surely limits the rising of the capacitor voltage and there must be some charging current also flowing into the battery from the cap.

The phenomena of your needing to place the battery back into the circuit to get the "effect" again (after that the cap was fully discharged) is explained by also the 'wrong' value of the output capacitance at zero drain-source value: it simply much higher than 1.6nF and the battery voltage brings it within range.  (Just check your unused IRF640 drain source output capacitance in itself, not connected anywhere but to a C meter if you have one, first short circuit the gate-source pins with a piece of wire to really switch it off because the higher than 1nF gate-source input cap likes to store voltage for a longer time.)

There remains to explain your flat current trace during the ON time of the FET but unfortunately I cannot give a correct explanation yet. One possibility:
I think the mistery "flat current" trace of mainly zero value is not really zero but its average value is much smaller than for instance in the case of the 10 Ohm resistor. Because the FET switched output resistance looks like to be higher than 10 Ohm due to the low duty cycle drive it receives at the gate-source input.  I know this does not fully explain it though, will be thinking on it. And others here are kindly invited to share their thoughts.

rgds, Gyula
   
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@gotoluc

As usual nice videos and interesting results.

One of the things I discovered recently while working with all sort of LEDS and coils for making my five videos is that the volt meter or the scope probes can inject power in the circuit. To see if this is possible, just take the lowest voltage LED you have, preferable in the 1 volts range and just put your volt meter to it and see if it lights up. Then try your scope probe. I was amazed to see mine light up and this could explain what is going on.

Especially when doing works with low voltage/amperage.

Eventually, you may consider winding a nice bucking primary on your small toroid and do other tests with it. That's my next direction.

But keep on go'in man.

wattsup

Hi wattsup,

thanks for your post.

That is one thing I did check to see if the effect continues without any meter connected before starting this topic as I have had that happen in the past. However it did not change things.

I think it's as Gyula has explained.

Luc
   
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Hi Luc

Good work as usual.
I would have thought you should have your Chan 2 of the scope on DC to measure current as a constant current drawn across the resistor will be a dc offset and this wont show on the AC setting.

There can be energy passed from the gate of the FET, i have seen switching waveforms on some of my tests with my source volts switched off, whether this is enough to cause your effect i am not sure.

Peter


Thanks Peter for your post :)

Your guess was close ;)... I think Gyula's explanation (posted above) is what is going on.

Luc

   

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Sounds likely, still the thrill of a possible OU device has charged us up with enthusiasm.

One day one of us will find it  ;)

Peter

   
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Hi EMdevices,

Thanks for the explanation I fully agree, I was a bit 'rusty' when was pondering on this question. Later on I wrote to Luc that the resonant circuit created at the FET output represent a high impedance hence the current pumped into it at that frequency should be small.

On the question of the current spike when the FET switches ON: well the multiturn - multilayer toroidal coil may have enough self capacitance to explain that.

Thanks,  Gyula
   

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It's not as complicated as it may seem...
Thanks EM.

We should start a thread: "EM on EM"  ;D

.99
   
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@EM

Yes thanks for the explain. I was seeing the same thing on my current experiments. I had bought a huge 0-50mA analog display that I put into series with my pulse generator and cannot see it even move, maybe a bit. But with the amount of LEDs being lit, I should have seen it move more then that but I think your explanation covers why.

@poynt99

Instead of "EM on EM", I would prefer "EM clones his brain and wattsup is his first client".


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Hi everyone,

I have some good news.

As I write this the coil is self running (NO BATTERY ATTACHED TO CAP BANK) and the voltage is at 19.45 Volts DC and rising ;D

I also added a pickup coil with diode, capacitor and 50K Ohm load and it is at 1.03 volt dc.

I changed my MOSFET gate driver to a SG3525A circuit which I built some time back and immediately had much more success compared to the 555 PWM.

Here is the new video: http://www.youtube.com/watch?v=_sicsnUq_a4

The core of the toroid is a regular ferrite 1"-3/8 OD, 13/16" ID and 7/16" high. The coil is wound 5 layers of 24 AWG on each half. One wound CCW and the other CW. Inductance is 1,050mH and 7.6 Ohms with coils bridged together.

I will be limited in time to answer questions for the rest of the week.

Luc

Here is a base circuit for the SG3525A:
   
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Luc,

Looks good ...but you must opto isolate the drive circuit to remove the possible source.

The  buck boost effect of the inductance will give you a higher voltage

Nicely demonstarted and clearly shown , thanks
   

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I just did some calculations.
Your 2 blue caps 3900uF each using the volts readings in the video averaged over a time period 196 seconds is giving you an average charge power of 61.2uWatts.

The 0.85 Volts across your 50k res is dissipating another 14.45uWatts.

So that's a total generated power 75.65 uWatts (Micro Watts)

I think the clue is that you are getting better performance using the new driver board, looking up the chip specs, it is very power hungry so at this point in time you wont be closing the loop with the driver.

I would try putting a resistor in between the Fet gate and driver chip and see how it affects the amplitude of the resonance. start with a smallish value and increase it in value and make sure your fet is still switching correctly.

Peter

   
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Luc:

I looked at your first two clips and read the comments.

My first comment is that you need to make schematics of your circuits.  They can be as simple as hand-drawn sketches like Lidmotor does or something like a .pdf file that you provide a link for.  I am sure that there are lots of free schematic drawing programs out there.

You may not be aware, and perhaps I am different from the average, but you would not believe how much extra mental effort it takes to watch your clip, listen to what you are saying and try to understand it, while at the same time trying to figure out what the actual circuit is.  Your mind is trying to pick up clues about the circuit from what you are saying and what the visuals are as you go along.  Even for simple circuits, the whole thing is very mentally taxing and draining.  You may not be aware of this because you are in your own fishbowl and it's all self-evident to you.  It's much different from outside the fishbowl.

If I can be so bold as to make another comment, it's that you can't selectively ignore the data that you are looking at.  In the two clips I saw you point to the current trace several times and say that it is "flat."  It's not flat at all, you can clearly see a spike event at each transition of the MOSFET switch.  Those spikes mean something and you have to try and figure out what they mean.

Anyway, since I don't know what your circuit is, I can just make a generic comment:  It looks like energy from your 555 signal source is being coupled through the MOSFET gate capacitance and charging your capacitor.  That's all I can say because I feel like I am in the dark.

Certainly coils themselves are not a source of energy.  The notion that you can put current through a coil, then open the circuit and get more energy back from the back-EMF spike is false.  I don't know if you are suspecting the coil switching is doing some magic, but I just wanted to say that for this thread in general.

MileHigh
   
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Hi everyone,

I took some time off today to do some more experiments as I can't stop thinking about this setup and I'm sure that goes for many of you.

I made 2 new video's to which I hope will answer some questions and help understand the effect.

Sorry I can't answer individual questions. I rather use the limited time I have to continue experimenting and posting videos that will hopefully cover everything one would need to make a successful replication.

Can anyone please explain how the 3vpp measured gate leak between the source and drain is capable of keeping the circuit running NOW at 30vdc, 55KHz with 50% duty cycle without using any current and maintaining 0.56vdc on the pickup coil with 49,850 Ohm load. Thank you for your help and time

Test 5 video: http://www.youtube.com/watch?v=RhrYzBld74w

Test 6 video: http://www.youtube.com/watch?v=UflGpzijWIA

Luc
   
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Hi all,

please find attached circuit. If someone can clean it up and make it look good that would be great.

Thanks

Luc
   
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Good work Luc!

 Lindsay is correct - you need an optical isolator between your signal source and your gate

   
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