This is my rectifier circuit and voltage multiplier.
See Circuit Diagram below.

Misc. Items

This is my test bed.

And here we are making power.

Some details:

If I supplied 12 volts for the rotor field I get 36 volts at 700 RPM (no load), not too bad.

If I connect the field to the output of the alternator circuit, it "boot straps" at 700 RPM and starts making power.  Maybe larger magnets would get the alternator to "boot strap" at a lower RPM.

My E-Mail for comments or questions:

Misc. Items