Omron SYSMAC C200H-NC111, Руководство по эксплуатации

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tation amounts, for example, computes the error between the target value
and actual movement value, and zeroes the error through feedback. The dia-
gram below illustrates the basic configuration of a semiclosed-loop system.
Rotary encoder
Tachogenerator
Servomotor driver
Servomotor
Position output
Error counter Power amplifier
Position feedback (feedback pulses)
Speed feedback
Target position
1) First, the target position is transmitted to the error counter in units of en-
coder pulses. The servomotor driver must be able to handle digital input.
2) The motor rotates at a speed corresponding to the speed voltage. The ro-
tary encoder connected to the motor axis rotates in sync with the motor, gen-
erates feedback pulses, and subtracts error counter contents.
3) Consequently, the encoder rotation is equivalent to the target position, and
the motor stops rotating when the error counter count and the speed voltage
become zero.
4) While the motor is stopped, the rotary encoder constantly maintains the
stopped position through correction. In the event that the motor axis slightly
moves, the error counter receives a feedback pulse from the rotary encoder,
whereby a rotation voltage is emitted in the reverse direction from which the
rotary encoder moved, causing the motor to rotate toward its original posi-
tion. This operation is called servolock or servoclamp.
5) In order to execute positioning with acceleration and deceleration, target
positions are set consecutively in the error counter for processing.
6) The target position becomes the count for the error counter and controls
the motor by conversion to a speed voltage for the servomotor driver. The
position thus equals the total count of target positions and the speed will de-
pend on the target position per unit time.
Control System Principles
Section 1–4