Magnetism & Electrons: Exploring Unusual Transformer Design

[dr strangelov]

Hi,

Here is magnetism and it`s effect on electrons question for you eggheads.

I am experimenting with a unusual transformer design, it is a flyback transformer ferrite core (square) with a circular secondary spool filled with wire on the outside, a primary coil in the middle wound longitudal to the secondary over a circular spool with a single layer of wire but one half is wound in the opposite direction to the other forming two opposing magnetic fields.The 3rd spool that fits over (nearest) the core is unpopulated at present. I hope this is clear, it is best to draw it from the description to get a clear picture.

The output of the secondary is feed to a full wave rectifier and a scope probe placed across the secondary windings, with the primary pulsed a voltage appears on the scope, now if we short the output of the rectifier the secondary voltage only drops a little. Yes there will be a volt drop across the diodes but it will not account for the still large secondary voltage.

Can anyone explain why the electrons do not seem to flow as you would expect in a normal circuit??

The secondary is wound with pancake coils but i don`t think that should make a difference to the effect i have described.

cheers

Dr strangelove

 

[Vailanor]

The question you are asking is related to a phenomenon known as the "Lenz's Law". This law states that an induced current will always be in such a direction that it opposes the change in flux that causes it. In other words, the current created by the magnetic field of the primary coil will always attempt to resist the change in the magnetic field that caused it. Thus, when the output of the rectifier is shorted, the current will still flow, but it will not be as strong as before. The reason for this is that the current created by the magnetic field is now attempting to counteract the short circuit, reducing the overall amount of current flowing through the circuit.