Generator control system

Claim 1

IN AN ELECTRICAL GENERATING APPARATUS INCLUDING A PRIME, MOVER, A FUEL SUPPLY FOR THE PRIME MOVER, AN ALTERNATOR DRIVEN BY THE PRIME MOVER AND A FUEL CONTROL VALVE FOR THE PRIME MOVER, A NULL SEEKING ALTERNATOR CONTROL SYSTEM OF THE CHARACTER DESCRIBED, COMPRISING: MEANS FOR SENSING THE FREQUENCY OF SAID ALTERNATOR AND FOR DEVELOPING AN ALTERNATING SIGNAL CORRESPONDING WITH THE DEVIATION OF SAID FREQUENCY FROM A DESIRED FREQUENCY; MEANS RESPONSIVE TO A CONDITION OF THE LOAD CURRENT FROM SAID ALTERNATOR FOR DEVELOPING AN ALTERNATING LOAD CONTROL SIGNAL; MEANS RESPONSIVE TO THE POSITION OF SAID FUEL CONTROL VALVE FOR DEVELOPING AN ALTERNATING SIGNAL IN ACCORDANCE WITH SAID POSITION; A TRANSISTOR AMPLFIER HAVING AN INPUT CONNECTED WITH SAID SIGNAL DEVELOPING MEANS COMBINING SAID FEEDBACK SIGNAL IN INVERSE RELATION WITH SAID FREQUENCY AND LOAD CONTROL SIGNALS; AND A PHASE SENSITIVE DEMODULATOR CONNECTED WITH SAID AMPLIFIER AND HAVING A CONTROLLED POWER OUTPUT CONNECTED WITH SAID FUEL VALVE, CAUSING MOVEMENT OF SAID VALVE UNTIL SAID LOAD CONTROL AND FEEDBACK SIGNALS CANCEL.