Patent ID: 8643344

Claim:
A condensive load protection device of a self-excited generator including an automatic voltage regulator which supplies a current obtained by commutating an output of an excitation winding wound in a generator to be driven by an engine to a field winding according to fluctuation in a generator output voltage, comprising: a field current control driver configured to be connected to the field winding in series and controlled to be ON/OFF by a drive circuit of the automatic voltage regulator to supply a field current to the field winding; a condensive load protecting rotor short-circuit driver configured to be connected in parallel to the field winding, and supply a short-circuit current to the field winding by being turned ON; a bootstrap circuit configured to be connected as a drive power supply of the field current control driver and the condensive load protecting rotor short-circuit driver, and include a capacitance portion in which charges are accumulated when the field current control driver is ON; and control means configured to always operate the field current control driver and the condensive load protecting rotor short-circuit driver in a mutually inverted manner, and be connected to and electrically isolated from the condensive load protecting rotor short-circuit driver by a photo coupler.