Abstract: In a wind-driven generator system, the generator load curve is matched to the wind-driven rotor characteristic by an electronic field current control which is responsive to the rotor speed. A tachometer circuit produces pulses the repetition rate of which is proportional to rotor speed. The pulses are counted in a predetermined time interval, and a stepwise control of field current is effected in accordance with the count. Switching from the first step, in which field current is zero, to the second step, in which field current is relatively high, takes place at a count which is spaced by intermediate counts from the count at which switching takes place from the second step to the first step.

Abstract: A generator load curve is precisely matched to a wind-driven motor characteristic by means of a rotor speed-responsive tachometer effecting stepwise control of field current in the generator. Several variations of the tachometer circuit are described. Field current is controlled by an amplifier, and voltage regulation is effected by an override circuit disabling the amplifier.