You are right. From what I've read, the wind generator's output if a function of it's RPM's. However, they are calling them 48 volt alternators. I'm going to guess the magnets are an energy saving device, so when there is no wind ther is no current drain.
Come to think of it, my old 1966 triumph 650 motor had a magnet connected to the crankshaft and the stationary coils around the magnet is where the induced voltage was made. So spinning a magnet really is a new thing. Back then, after the AC went throught the diodes, triumph used a zener diode as the voltage regulator, sending the excessive voltage to ground. Wind generators may be dumping their excessive voltage.
Everyone seems to be getting side tracked with terms and definations.
A friend wants a 48 v delco alternator to charge 4 12v batteries in series.
I need information on how to trick, modify, the voltage regulator to make 48v. So it seems everyone thinks it's possible, no one can tell me how to make it happen.