The dual primary coil idea

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I had an idea that i feel need to be investigated....so here it goes...

imagine a transformer having two primary winding and one secondary winding... the secondary being in the middle of the two primaries what decouples the two primary a little

the two primary will have oposite fields so they will be pulsed at the same time for start than they must be sequencialy turned of

the idea is that if they are pulsed at same time their magnetic fields will cancel but when they are sequence turned off one first and next the other it will create an ac voltage across the secondary, one half cycle per primary turned off

as the coils are oposite in magnetic field they should saturate with current very fast, allowing  both to have their time of collapse..

the main idea is that we can possibly charge both coils at same time and as we sequence turn them off they will have a sharp flux change

to achieve this we need a power supply and two independent switches

the timing circuit could be made with 555 timers and  some inventive spirit

the two pulses must start in sync than one will terminate, and the other remain a little and than it terminate too and than there is a time with both off for the collapse to end for start over again..

so maybe one timer being the master clock and the second being a monostable

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when the first switch open a clamped voltage will appear across the other primary and secondary... on the other primary the voltage will be clamped to the source voltage level since its already connected to it... when the second switch opens a higher level voltage should exist but it will also be clamped by the diode that exist in parallel with the switches..

so the output in secondary should be proportional to the turns count

however i´m not sure the current will be conserved...

tests need to be done

we need a circuit for generating this kind of pulses...

(http://www.ionizationx.com/index.php?action=dlattach;topic=3178.0;attach=15076)

the duty cycles should be 33% for t1 66% for t2 and 33% t3

of course maybe if for example  t1 could be reduced to 1% than  t2 would represent 49% and t3 the other 50% or something like that
 

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You could instead ground the center tap, then connect the positive outputs of a flip/flop - or relay - to the a and b inputs of the primaries. This is called "splitting the positive".

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You could instead ground the center tap, then connect the positive outputs of a flip/flop - or relay - to the a and b inputs of the primaries. This is called "splitting the positive".

Wouldnt it be just the same?

i usualy prefer to switch on the low side because is much simpler...

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I think i just found a way of doing it... similar to what i did in the fracture cell ckt..

Basically is one 555 timer astable operation and two comparators making 2x  0 to 100% duty cycle variable frequency generator

connected to two high voltage and amperage igbts having diodes and some tvs for safety in parallel with it

the simpler the better

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the simpler the better

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Hi Fabio,

You said to put your secondary between the two primaries. Is your objective to produce bucking fields, with splatter potential energizing the secondary, or do you just want to produce a sine wave from chopped DC?

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I had this feeling that the primaries must be coupled more to the secondary than to each other however as they make part of the same core they will be coupled anyway...

my objective with this would be to create a different kind of voltage output in the sense that when you pulse both oposite polarity coils at the same time no induction will result as you see on the drawing, however when the first primary is interrupted a positive voltage will come out from the secondary and when the other primary is interrupted a negative voltage will result...

my guess would be that it could maybe generate a huge spike too i´m not sure how the waves output will be exactly but i tried to show in the drawing a prediction...

i´m not certain about the spike because once we interrupt the current in one primary the other primary already have also maximum current thereto no change in flux actually.. the change in flux comes only when we interrupt because when we activate them together they result in no flux... its prety much like having a high turn ratio of one to the secondary number of turns... but not exactly as we can simply turn half of the turns off and so on sequentially ...