H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
H02P5/00—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors
H02P5/46—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors for speed regulation of two or more dynamo-electric motors in relation to one another
H02P5/48—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors for speed regulation of two or more dynamo-electric motors in relation to one another by comparing mechanical values representing the speeds
H02P5/485—Arrangements specially adapted for regulating or controlling the speed or torque of two or more electric motors for speed regulation of two or more dynamo-electric motors in relation to one another by comparing mechanical values representing the speeds using differential movement of the two motors, e.g. using differential gearboxes