| 摘要 |
To control the operation of an actuator motor (48) an input signal is compared with a feedback signal at a summing junction (22) with the resultant error signal used to bias off the output of a sawtooth generator (30) by pulse width modulation in a modulator (28). The pulse width modulated signal and three commutation signals from an optical detector (34) are input to a commutation circuit (32) that decodes the input by means of a programmed read only memory into a six state drive voltage that is applied to optical isolators (36), (40) and (44). Two of the six states from the commutation circuit (32) are input to each optical isolator that provides an output for driving a power stage. The optical isolator (36) drives a power stage (38), the optical isolator (40) drives a power stage (42) and the optical isolator (44) drives a power stage (46). Each of the power stages has an output connected to one motor lead for the delta wound motor (48) that includes velocity limit protectors (76) through (78). Commutation signals to the commutation circuit (32) are provided by the optical detector (34) that responds to the rotation of a commutation disc (102). Rotation of the rotor (54) of the motor (48) is gear coupled to a feedback potentiometer (62) having an output coupled through a compensating lead/lag network (64) to be compared with the input signal.
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