Here are the specs I am working with.
The circuit needs to run 1 to 3 alternators.
Rotor resistance is 1.3 ohms, so pretty high current.
The 3 alternators should be able to be turned on and off individually.
Option to have one circuit to run 2 alternators.
Voltage adjustable for either two 8 volt batteries or a single 12 volt battery. He will add a voltmeter.
So anyway that's how I got here. I'm open to other ideas, but those are the constraints.
Attached is the asc file and a png.
It is no longer PWM just on and of at the set point.