| 摘要 |
A DC motor is speed regulated by continuously, maintaining current in the motor windings and varying the current between a higher and a lower current level during a subsequent sector or period of rotation in accordance with the velocity sensed during the present sector or period of rotation. To obtain closer regulation, the higher and lower current levels have only a small amplitude difference and the system is adaptively controlled by sensing the number of sectors of a series of such sectors during which the higher current level is supplied to the motor. If the percentage exceeds 70%, both current levels are incrementally increased and if the percentage is less than 30%, both current levels are incrementally decreased. The regulation and adaptive control are used in two stages, initially sensing velocity during each revolution of a series of 20 revolutions and switching, when synchronized, to sensing velocity during each of 74 sectors of a series that form one revolution. |
