Jeff Rosenbury said:
Inductance is a form of stored energy. Currents generate magnetic fields. These fields build as the current builds, and they store energy. When the current tries to stop flowing, the field collapses. The field transfers its energy back into pushing a flowing current. This results in a slowing of change -- a phase shift.
In a transformer current in the primary creates that field and the field then induces current in secondary. In an ideal transformer, all the energy is coupled from the primary and used in the secondary. In a non-ideal transformer, some of the flux escapes and doesn't couple. This might instead induce eddy currents, straight inductance, copper losses, etc. These are modeled as an impedance.
This is where I'm rusty, because all I think of between coils is that (forgetting about leakage flux for the time being) that the flux running through the core, is the same, thus using faraday's law there is a voltage induced on the secondary coils, and a back EMF on the primary.
So what does it matter if there is energy stored in the form of inductance? (in the air through leakage, or in the core through coupling) As long as the flux is flowing between the coils, what does inductance matter? It seems irrelevant, can you explain the role?
I know in an ideal TX you would have a core with infinite permeability, thus the reluctance is zero, meaning that the inductance is infinite, but again, what does this matter? (as long as faradays law is in action)
I don't disagree with what you said, I'm just not making the connection between the operation of an inductor, and I'll give you a hypothetical:
Say you had some magic excitation source, and some magic core, where the supply of voltage just went up forever (there was a constant dΦ/dt), then there would be a constant voltage on the secondary and the magnetic field would never collaps.
Jeff Rosenbury said:
If you are trying to build an electronics regulator, other factors will typically dominate. Line voltage varies by somewhere around 10%. Ripple is typically a problem, etc. There are some nice linear supplies which fix these problems, but at a cost. (Beware the dropout voltage; you will still need you equations to check that.) Switching power supplies are more efficient, but have more noise.
No, all theoretical ATM.
Jeff Rosenbury said:
On the angle thing (How did you make the symbol, BTW?): No, the angle is the angle between the unloaded voltage and the loaded voltage. Notice how in the first diagram the loaded voltage is actually higher than the unloaded voltage. (This is because most of the impedance is reactive with very little resistance.) This link is more for power engineering. Such situations are counter-intuitive, but occur in power situations. I'm more of an electronics guy.
On the reply green bar there's a little sigma sign for symbols, it's in there.
H'mm ok, it's the angle between loaded and unloaded, that makes sense. So the voltage induced on the secondary should be pretty much exactly in phase with the primary excitation?
Thanks
)
