Thane Heins BI-TOROID TRANSFORMER

[SchubertReijiMaigo]

Hello everyone, I have played with FEMM last two days... I have made a GIF to show magnetic flux in the BTT with and without air gap between path 1 (small) and path 2 (2 times bigger). The air gap is about 0.1 millimeter...
The air gap add more reluctance and linearity comportement of the path 1 and symetrical distribution of BEMF.
All coils have 100 turns and 1 amp flowing current. Each flux path is tested separetly... The flux of primary is the initial flux, the other flux is simulated BEMF flux. Enjoy !!!

[ramset]

teslaalset
Quote;
B.t.w. In my country (Holland) private consumers do not pay for consumed blind power.
But companies do pay for this already.
---------------------------------
Sir
Its My job to ask the dumb questions [as rarely as possible].

Whats "Blind Power"?  -> ?

Chet

[CRANKYpants]

Thane, to avoid misinterpretation, here's the Femm result in case no secondary load is present.
You'll notice that indeed there is no flux in core3, as one would expect. I don't understand why there is some in your setup in case there is no load......

WE ARE ONLY INTERESTED IN FLUX CHANGE PERCENTAGE - NOT FLUX MAGNITUDES ON THEIR OWN.

BUT FOR ARGUEMENT SAKE - I WOULD SUGGEST THAT THERE IS ALWAYS SOME RADICAL STRAY FLUX IN CORE 3 EVEN ON NO LOAD.

(The earlier results I showed had some secondary load current included. That is why they have flux in core 3)

AND MORE IMPORTANTLY YOU ALSO SHOWED HOW A LOADED SECONDARY COIL 1 WILL REDIRECT FLUX AWAY FROM ITSELF (DUE TO ITS IMPEDANCE AND RELUCTANCE INCREASE) INTO THE OPPOSITE SECONDARY WITH LESS LOAD/IMPEDANCE/RELUCTANCE. SECONDARY COIL 1 IN THIS CASE WILL SHOWS 0.0 LOAD VOLTS.

BOTH COILS NEED TO BE LOADED SIMULTANEOUSLY TO FEED EACH OTHER THE FLUX REQUIRED TO MAINTAIN A VOLTAGE ACROSS THE LOAD(S).

The measurement method you use is a bit doubtful though, using a current clamp to measure magnetic flux. Those clamps are normally made out of ferrite (so high permeability). Putting such clamps on a transformer core should not give any flux in the clamp core, even if there is flux on the transformer core. But you showed it obviously does. So, big question marks here.

I BET THE CLAMP ON PROBE AT CORE 3 IS READING THE FLUX VARIATIONS WHERE CORE 2 MEETS CORE 3. A CLAMP ON CURRENT PROBE IS JUST A GAUSS METER WHICH READS MAGNETIC FLUX AROUND A WIRE AND CONVERTS IT TO AMPS. IT WILL READ STRAY FLUX AROUND A TRANSFORMER CORE IF IT IS CONNECTED "PROPERLY" THAT IS WHY IT IS LEFT OPEN AND "INCORRECTLY" CONNECTED DIRECTLY TO THE CORE SUCH THAT THE CORE COMPLETED THE CLAMPS MAGNETIC FLUX PATH.

AT ANY RATE AS I MENTIONED ABOVE IT IS THE FLUX CHANGE % THAT IS IMPORTANT EVEN IF THE "NO LOAD" FLUX READING AT POSITION CORE 3 IS 10 AMPS - THE QUESTION IS HOW DOES IT CHANGE FROM NO LOAD TO ON LOAD.

I would just use a few (10-20) detection windings on those cores to measure the voltage over those windings with an oscilloscope. That probably will give you a more reliable and accurate representation of the local flux.

YES AND IT WON'T COST YOU $400.00 EITHER!

CHEERS
T

[CRANKYpants]

Hello everyone, I have played with FEMM last two days... I have made a GIF to show magnetic flux in the BTT with and without air gap between path 1 (small) and path 2 (2 times bigger). The air gap is about 0.1 millimeter...
The air gap add more reluctance and linearity comportement of the path 1 and symetrical distribution of BEMF.
All coils have 100 turns and 1 amp flowing current. Each flux path is tested separetly... The flux of primary is the initial flux, the other flux is simulated BEMF flux. Enjoy !!!

THAT "GIF" SHOULD BE MORE ACURATELY CALLED A GIFT! 

THANKS
T

[CRANKYpants]

Mr T
Holy Crap!!,I had no Idea!!
Whats that red one ?Runs on wood gas?Chet

NO THAT RED ONE IS THEIR HHO BURNING BIKE - THAT BLACK THING IS THE WATER TANK!

CHEERS
T