I got my hand on an old car alternator. I can't figure out how it works. What bugs me is that it look like all the phases (and neutral) are connected together right at the output of the stator coils.
When I test the resistance between any of the four yellow wires I get 0.3 ohm or something like that.
When powering the rotor and turning the alternator with a drill there is a DC current at the output.
Here you can see the 4 wires coming out of the stator, the topmost being neutral.
I must be wrong somewhere but I can't get my head around this.