Re: Winding BiTT with C shape winding tool

Body

Heinz magnetic core circuit reduction to an EI-core with an air gap

And the circuit with references for magnetomotoric forces, reluctances and magnetic fluxes:

Regards
Ole



---In [email protected], <onielsen@...> wrote :

 Hi Kone,

The circles represents the magnetomotive force (mmf) and the rectangles represents the reluctance (Rm) or magnetic resistance to the magnetic flux ('magnetic current'). The mmf is A (Ampere) or A X turns which is the total amount of current going around the leg. With these three parameters a magnetic circuit works like Ohm's law for an electric circuit.
The lines represents magnetic conductors having no reluctance (ideal conductors).
 https://wiki2.org/en/Magnetic_circuit https://wiki2.org/en/Magnetic_circuit

"MAybe most important or just as important as including the reluctance value to the relcutcance boxes, is that there is, I count six "three-way" junctions to the Bitt transformer core drawing, while the Jensen has only two...at the top and the bottom of the primary..."
The reluctance for the different legs and parts making up the magnetic circuit can be calculated. By using tables of magnetic properties the parameters for iron can be found and the cross sectional area of the legs and their lengths cam be found. This makes it possible to calculate the reluctances.

When two resistors (or reluctances) are in series the resistance can be substituted with a single resistor having the value of the two series resistors added. For resistors in parallel they can also be substituted with a single resistor having the value of the two paralleled resistors (the value isn't just added when in parallel). By using these two rules the reluctances can be reduced to the simple circuit with few reluctances and some ideal magnetic conductors connecting them. Of course a real transformer core has its reluctance distributed along the magnetic conductors. The schematic model makes it much easier to calculate the circuit than using distributed reluctance along the magnetic paths.

Regards
Ole


 

---In [email protected], <konehead@...> wrote :

 Hi Ole
 I think the drawing of the Thane transformer is not quite correct, as I assume the circles represent the three coil windings, and the rectangular boxes represent  the transformer legs "reluctance" as you call them...:"nagnetic paths" might be another term to use for those boxes and it is important that their magnetic-resistance fo magnetic flow  ("reluctance" to flow) should also be included in each those boxes, as they all are not the same resistance to magnetic flow, some paths have skinny transformer legs, some have much thicker transformer legs,
 For example the large rectangular box in your drawing i in my Bitt core made of florist wire, is three times thicker than the rest of thoise inner transformer legs.
 This is the advice that Gerry gave to me a couple weeks ago, since you want to make sure that the magnetic flow has a very strong path to the opposite side secondary....So I added three times the number of florist wire lengths to my core "perimeter"  and it is three times thicker
 Tthere should also be three more rectanfular reluctance boxes in the drawing, each underneath the three circles representing the coils, this regardless of the thicknesses of the cores, it is just something missing in the drawing.
 

 MAybe most important or just as important as including the reluctance value to the relcutcance boxes, is that there is, I count six "three-way" junctions to the Bitt transformer core drawing, while the Jensen has only two...at the top and the bottom of the primary...
 

 And the three way junctions being excluded are actually the most important detail of the BiTT transformer! As those two outside three way junctions on the left, and the other two on the right are where the back-currents "Decide" which route to take, and that is, back to the primary and reflect as extra draw and never overunity, or back across to the opposite side secondary, where the power produced in the secondaries becomes additive-power (coherent?)
 

 ciao
 Kone