초록 ▼

In a pulse-width-modulated servo motor control system, a signal indicative of the average terminal voltage of the servo motor is fed back to stabilize the response of the control system. Under normal conditions the feedback signal is representative of the velocity of the servo motor output shaft and

In a pulse-width-modulated servo motor control system, a signal indicative of the average terminal voltage of the servo motor is fed back to stabilize the response of the control system. Under normal conditions the feedback signal is representative of the velocity of the servo motor output shaft and thereby operates to stabilize the control system response as a function of the output shaft velocity. Under adverse conditions tending to increase the power supplied to a motor, the feedback signal increases in a manner to limit the power supplied to the motor and to maintain the control system bandwidth substantially constant.

대표청구항 ▼

A feedback control system for controlling the output shaft of a servo motor, comprising: means for generating an error signal as a function of the difference between a desired shaft position and the actual shaft position; means connected to said motor for developing a feedback signal as a function o

A feedback control system for controlling the output shaft of a servo motor, comprising: means for generating an error signal as a function of the difference between a desired shaft position and the actual shaft position; means connected to said motor for developing a feedback signal as a function of the average terminal voltage of said motor; means for combining said error signal with said feedback signal for decreasing the magnitude of said error signal and for forming control pulses therefrom to define energization periods for said motor; motor control means including an energization circuit path effective during said energization periods to connect said motor to a source of direct voltage, and a discharge circuit path effective during an inductive discharge period following an energization period to clamp the reverse inductive voltage of said motor at substantially that applied to said motor during said energization period, the relationship among (1) the energization and discharge circuit path time constants, (2) the duration of said energization period, (3) the repetition frequency of said control pulses, and (4) the L/R time constant of said motor being such that each of said discharge periods is substantially equal in duration to an associated energization period and that a counter EMF voltage is developed in said motor during a time period between the termination of said discharge period and the beginning of a subsequent energization period whereby the continuous average motor voltage corresponds substantially to the back-EMF of said motor and the response of said control system is stabilized in accordance with the velocity of said motor output shaft.