Saturated alternate path transformer

[Jack Noskills]

Below is a picture made by broli of the very first OU transformer I made over a year ago. Primary is in the middle and secondaries outside. My crude implementation using scrap parts showed about 1.8 COP. I used iron core and 1.8 was directly related to ratio of area between flux paths. Details are in BiTT thread but a short summary below.

When no load connected, both coils showed about 110 volts or so. When one secondary was shorted, volts in the other that was unconnected doubled and also the current in it doubled. This is the basic behaviour of secondary feedback as explained by Thane.

This still consumed power from source so I kind a dropped thinking about it. Now that I am a bit more experienced I realised there is much room for improvement. Idea is to bring core in primary into saturation by shorting one secondary, then add a parallel capacitor to primary. When tuned, there is maximum reactive power going on in the core but no real power is consumed. Now consider what happens in primary when power is taken from secondary that is left ? Nothing. Reactive power can be taken to load and no power is consumed in primary because resonance is not destroyed because primary core is saturated. Hence secondary that is used as does not affect primary. Instead it feeds the other secondary and flux there is increased so secondary gives even more flux back.

Look at the picture again, you will notice that flux is divided into two parts so in order to bring primary into saturation tricks are needed to make flux back to source stronger than what is coming. There are several ways:

1. bifilar windings in secondary, it has twice the inductance compared to normal winding.
2. tin/silver coated wire in secondary. It has three times the inductance compared to normal wire.
3. Higher permeability core in secondary. For example take metglass C core and fit ferrite rod in the middle/on top of C core. You can easily get ten's of times of differences using modern cores.

If you can play with core permeabilities, then bifilar is good also in primary. It allows the use of higher frequency and that is where the power is.
I wanted to put this idea here because I don't have suitable parts to proceed. If you want to collect the prize then make it and share your results in this thread.

[EssieRios]

Ta strona jest uważana za bardzo pouczającą, ale chciałbym wiedzieć, czy te dane zostaną usunięte i dlaczego.

[infringer]

Interesting thought. I am not sure of this whole thane thing or whatever shorting a second secondary coil how is it shorted to ground or to itself IDK?


What are the materials list?


What is the process for building?

[F6FLT]

Below is a picture made by broli of the very first OU transformer I made over a year ago.
...

I see nothing here about OU. Why "OU"?

[seaad]

What are the materials list?

Hi Jack Noskills

Did you use the same scrap SiFe? material (plates?) in both primary and secondary?
Do you have any readings from your test?
Input / Output voltage, current, frequency and most important input phase angle.
Resistive load?

Regards Arne