Bucking Coil Inverter

[AetherScientist]

edit: here is a link to the naudin bucking coil experiments. My Bucking Coils

The question is, how can the bucking coil arrangement, induce a current into the L3 secondary on collapse, if it does not do so when current is initially pulsed into it.
Still thinking about that one me self.

The link is yours? I mean if you have performed the experiments.

[SkyWatcher]

Hi aetherscientist, no the link is not mine, however i have performed the experiment.
I built a straight ferrite tube core and placed bucking coils face to face on core, with a full length secondary underneath and it did show same results as naudin.
That of no induction to secondary upon energizing the series bucking primary coils.
Then induction within secondary coil and led bulb lighting upon collapse of primary bucking coils.
peace love light

[Wistiti]

Hi Sky and folks!

Today i have some spare time so i decide to play a bit with these POC (Partenered Output Coil) The bucking coil as name by EMjunky.

After reading some old post, i decide to test what some folks here said about a kind of capacitance may happen between the primary coil and the POC . I mean here the distance between the primary and secondary .

I also tough about what some people think then the magnetic field must be better under (inside) the primary than over...

So i decide to re-do the first module i have done on the top of this tread with that concept in mind.

I use an 8 cm ferrite rod i have found in a old radio. I wrap the POC on it with 20 AWG magnet wire (4cm each coil). I wrap a 18AWG speaker wire over it (the thick insulation may do the job for the capacitance...) I secure the outside with tape.

The primary is drive by a blocking oscilator (joulethief). The transistor is an 2n222, the resistor is 1350 ohms.

The output (POC) is conect the midle together and the end together. The both midle go to one ac of a homemade 1n4148 bridge rectifier and both end of the POC go to the other ac of the bridge.

The - and + output go to a 16vdc 22000uf cap. I also use a 1n4007 blocking diode on the + of the cap for the final output.

I decide to use it for charge battery.

For now the result is quite interesting...

My source battery is 2xaa 1.2vdc 1900mah nimh in serie. My charging battery is 12vdc 7.2ah lead acid.

At the start (battery not connected) my reading is: Source--2.506vdc Charge--12.30vdc

Now (3 hours later) my reading UNDER LOAD is: Source--2.406vdc Charge--12.43vdc

I will let it run till tomorow and let you know about the result...

It is slow; but it seem efficient!

Happy holiday for everyone!

[Wistiti]

Ok after 5 run hours, i disconect the circuit cause my aa bat was deplete and i dont want to scrap them... I let everything rest for an hour and here is my reading.
source-- 2.411vdc Charge-- 12.40vdc

Sounds great!

[Wistiti]

Just in case someone whant to replicate; here is the skematic!

[SkyWatcher]

Hi wistiti, thanks for sharing.
Is the 18 gauge speaker wire covering both partnered coils, because the diagram looks like it's over just one partner coil, thanks.
I'm going to make one, i'll probably use 18 gauge magnet wire or 24 gauge and maybe 18 or 16 gauge lamp cord.
peace love light

[Wistiti]

Hi Sky!
The bifilar cover all over the 2 POC wire. I use speaker wire for the bifi for their thick insulation. (Create a gap between the primary and secondary is the idea here) So if you just have magnet wire under hand place something (tape, paper, etc...) between the 2 set of coil. Also use biger gage for the bifi than the POC to have much more turn on the bucking secondary than the bifi primary. For example when i connect my circuit on a single 1.5vdc aa battery with no load i can read 140vdc at the output. But of corse with few miliamps...

Anyway it is a fun project to play with!

I will be there for any question.

[SkyWatcher]

Ok, thanks wistiti, i'm working on it now.
I don't have 20 gauge magnet wire, so i'll start with 18 gauge magnet wire partner coils and i have some 16 gauge speaker wire for the parallel (bifilar) wire oscillator.
Going to use the ferrite beads or tubes again for this.
peace love light

[Wistiti]

By the way i use a fix resistor on the base of the transistor but mabe with a pot you can adjust to have beter result than mine...

[SkyWatcher]

Hi folks, Hi wistiti, finished building the wistiti POC charger variant.
Ferrite tubes are used as core.
18 awg. magnet wire is used for partner coils, wound opposite direction.
16 gauge speaker wire is wrapped over that, full layer bifilar.
NTE389 NPN transistor.
Neon protection.
1 kohm base resistor.
Could not achieve oscillation without adding a 100 nanofarad capacitor in parallel with the base resistor.
Using the high speed 1n4148 diodes, homemade bridge like wistiti.
Cobbled together capacitors i had on hand, totalling 20,000 uf, some are 25-35 volt.
Using a FUR460 ultrafast recovery diode from capacitor positive to battery positive.
Charging a somewhat crystallized 12 volt-4.5 Ah SLA, so probably not the best for testing, will use something else when i dig something up.
Using a single lithium ion cell for input battery, showing 3.92 volts at 120 milliamps or .47 watts and 12 volt charge battery is now at 11.58 volts, from 11.25 volts, about 20 minutes ago.
More tests and tweaking to come.



peace love light

[Wistiti]

Nice work Sky!
how much vdc did you have at the output?

ps: i seend you a pm you at ou.com

[SkyWatcher]

Hi wistiti, thanks.
At the full wave bridge dc output, it is outputting around 85 volts dc.
peace love light

[Wistiti]

Ok guys; last update about the Slow POC Charger.

Yesterday i run the test again for about 5 hours.

My source batt are still the same 2 x aa sanyo eneloop (By the way they wrote on it min 1900mah but on wiki they said they are 2000mah.)

My charge batt is a powerpack with an inside lead acid bat rate 12v 28ah.

I start by descharging my power pack from 12.85 to 12.05. I also fully charge the aa bat.

Aftrer everithing rest for about 45 min. before conecting my reading is: source= 2.83vdc charge= 12.28vdc.

I conect the circuit and let it run for 5 hours. Before i disconect my reading are: source= 2.49vdc charge=12.37vdc

I disconect the source and the charge and let it rest for the night (aprox 8 hours)

Now my reading is Source= 2.58vdc charge12.35 vdc...........

i will charge my aa and try to charge again this big bat!

Ciao!

[Wistiti]

Mabe something is going on with the lead acid batt...

Im looking to buy an other set of the same source batt. So i can do a real test by charging the same as the source...

Ciao!

[SkyWatcher]

Hi wistiti, thanks for sharing your results so far.
I would recommend charging lower voltage cells, placing multiple AA rechargeable in parallel.
Why, because as i have mentioned and observed before, normally when charging a capacitor, the input amperage is highest at the start.
However with this device, the input amperage is lowest at the start.
That is why this setup makes for a great battery charger in my view and why using the lowest voltage charging cells or battery is best, relative to source voltage.
Right now, i'm using the 3.8 or so volt lithium ion cell as input and one AA nimh rechargeable cell to charge.
Of course, many of those AA's in parallel would be ideal.
The input amps only rises 10 milliamps, when charging the AA cell, from 60 miiliamps to 70 milliamps.
Which is only a 38 milliwatt increase over no-load input.
Which is why i think a bunch in parallel could make for very efficient charging.
peace love light