Lenzless transformer

[Jack Noskills]

Excellent stuff !


Much more professional looking than mine. I needed more room for inner coils so I didn't use coil formers.  Winding them was a major pain, couple of hours at least.

[DilJalaay]

Hello Jack.
No, gap in core. All three secondary wires are of same direction same size and turns.
I also find that the middle coil is of more inductance than the side coils.

I think better is to avoid to make them in parallel and use separate capacitors for each,
as per your second drawing.

I am going to try this circuit for my primary.
As it state that it is self resonating(Auto Resonance).
So in this case L1 will be our Primary or driving coil. And we have to wind some extra turns for feed back
coil(L2) on L1. And sure we have to replace a capacitor for the HHO Cell.


What is your circuit for driving your primary?


Regs, DJ

[Jack Noskills]

I am using audio amplifier and Goldwave audio editor (free software) on my PC for creating waveforms. Headphone output from the PC is connected to audio amplifier and its loudspeaker output I connect to my test trafo.
Goldwave can create any kind of waveform using its expression evaluator tool, frequency sweeps using sine or pulse input for example.


You got scope ? Can you verify the effect that output does not affect input ?


Once that effect achieved all we need is to create resonant tank circuit in the primary and drive it using a spark. When spark hits at the correct moment oscillations in the primary coil increase, provided that there is new hit before oscillations have stopped. I think bifilar coil as the drive would work best, no capacitor needed, coil is the capacitor. Bifilar is good also because it has more self capacitance so it will ring longer and at higher frequency. As the oscillations increase without limit there needs to safety valve. For example use gas discharge tube which has 220 voltage in the drive side and then GDT with e.g. 600 voltage as the safety valve in the bifilar coil side. This GDT then connected to ground, or a metal object.


I forgot to test the effect of putting output coils in series. I did three experiments:


1. Outer coils shorted with itself, two shorted coils and output from the middle. When I connected load bulb, light intensity on primary side briefly increased and then returned to almost the same level it was.


2. Inner coil was shorted and outer coils connected in parallel to load. When I connected load bulb, light intensity on primary side decreased, barely noticed it.


3. All coils connected to load in parallel. When load bulb was connected, absolutely no visible effect on primary side.


This is why I think connecting load coils parallel works best, but this is just my testing. Maybe things work different for you. It is worth checking out different variations.


This circuit you posted is worth testing, but I think it is also good the get a feel of your initial condition.
What kind of frequency there needs to be at input before enough power is seen at output ?
Is there some limiter frequency that once it is reached there is no longer power at the output ?
Now that there is feedback coil in the primary in your drive it might ruin resonance condition, at least it differs from mine. Maybe better to take feedback by putting fourth coil in the output side ?


Anyway, possibly interesting times ahead.

[DilJalaay]

Yes i have scope and function generator.
ok. i am going to use this simple circuit to the tests.
you can also use this with your pc function generator.


please feel free to asked me if you want any test. i will do for you.

[Jack Noskills]

I don't have any transistors so my ability to test is limited to PC. Also as I don't have anything to view output except halogen. So here is what could be tested:


TEST1:
Connect all outputs parallel and directly to load, no capacitors.
Generate sinewave input. Monitor input and output when there is some load. Switch load on/off.
  Does load affect anyway to input ?
  How much current goes in output when load is on ?
  Voltage seen at the output when there is no load should be low. When load is connected also voltage rises because those three coils all feed each other. Can this be verified ?
 
Do frequency sweep, start from kHz range and increase it upto the limit of the core.
  Does increase in frequency also increase power at the output ?
  Is there a sweet spot ?


Frequency sweep using pulsed input. Change duty cycle 50% on 50% off, 25% on 75 % off, 10% on 90 % off.
  Should there be a diode on the input side to enable better oscillation in the primary ? I think it would be useful. Now the pulse acts like a spark gap, it hits the coil and it begins to oscillate. Using diode should make the oscillation to happen in the coil only.
  Is there anything different at the output ?
  Is there a sweet spot ?
  Maybe there needs to be a safety spark gap at the input. What if there is a sweet spot and voltage rises in the primary too high level damaging something ?


TEST2:
If above test was positive then lets proceed to next step. 
If you have capacitors those could be tested. But most likely resonant frequency will be low. To over come this, all coils should be done bifilar and we use coils as capacitors: Two wires side by side and one wire connected from the end back to start. Use same amount of turns so results can be compared with test 1.


If you find anything interesting then some scope pictures for all to see would be nice to have.


btw, I will be off line during weekend.


EDIT:
For pulse mode test, maybe it is a good idea to monitor output when there is no load. How long does the ringing last there and at what frequency it rings ? One pulse should be enough so we get sort of impulse response of the system. Same test preferably for both test scenarios I listed, normal coils and bifilar type coils. This gives a hint what kind of frequencies are best to use.