Abstract: The shaft of a wind turbine is connected to the rotor of a three-phase AC generator. The rotor windings, in turn, are connected to the rotor windings of a DC-energized, AC exciter via a differential frequency-converter. A frequency-detector, which monitors the output of the AC generator, is connected to the input of the frequency-converter to maintain the output of the generator at 60 Hz. A "real" power sensing circuit, connected to the output of the generator, develops a control signal which, when subtracted from a second control signal generated by a power management control circuit, maintains the power output of the generator at the maximum possible level for each particular power output from the wind turbine which drives the generator.