Abstract: A poly-phase high frequency alternator with a low-loss magnetic core is excited by a low-loss field coil that is part of a series resonant circuit tuned to a desired AC power frequency which may be 50 or 60 Hz. The series resonant circuit is excited at the resonant frequency. The resulting resonant behavior automatically provides the high driving voltages and sinusoidal energy storage patterns needed to efficiently modulate the field inductance at 50 or 60 Hz. Modulating the field at the desired AC power frequency modulates the alternator output voltage at that frequency. The poly-phase alternator output is rectified into a single phase and commutated with respect to the load at the zero crossing of each half cycle of the AC power frequency. This produces a single phase power frequency AC output.