Permanent magnet DC I fully understand... give it power and it turns, turn it and it gives you power. I broke many toys as a kid just to play with these concepts. But I was baffled when I once broke an old fan and found no permanent magnets in it.
I know understand the AC induction motor (regular household fan)... kinda.
But something that's still a mystery to me is the car's alternator. There is some kind of induction there too I guess. But when you turn an ac fan you do not get any electricity out of it. So how come it works?
I've been asking around to people that supposely know the stuff but all I get is that some of the energy produced by the alternator, is used internally to produce it's own magnetic field. Then this magnetic field is used to make electricity.
I reply that it looks to me like the chicken/egg paradox... what comes first? You need electricity to make the magnetic field so you could generate more electricity. But if you have no electricity to begin with, how you power those coils to get the whole thing going?
The only thing I could think of is that you use the car's battery to power the coils, create some magnetic field, then when it's turning, it generates some voltage, some of it keeps sustaining the field and the rest is your output. BUT... I remember that as a broke teenager I once used and old mazda for a full month with no battery, pushing the darn thing to get it started (I had good friends back then). So that theory should be wrong.
Now here I stand, 38 years old (give or take a year), at 3am, googling around, trying to understand the mystery of the car's alternator.
PS: I'm sure Danny knows this.... lets see if somebody can beat him to a decent explanation.