Yaskawa DR2 Sigma Servo - Manual (Page 26)

FOR FIRST-TIME USERS OF AC SERVOS
1.1.3 Features of Σ -Series Servos cont.
12
3) The most common usage of a speed/torque control Servopack is shown below:
• Using Servopack in Speed/Torque Control Mode (Speed Control)
Host controller
Position reference +
Speed
reference
Servopack
(speed/torque control)
Power
amplifier
(Analog
voltage)
Position
Convert
Torque
(current)
feedback
Pulse train
Servomotor
Position feedback
Encoder
Position control loop
Position
feedback
Speed
As shown in the figure above, a position control loop is formed in the host controller. The
host controller compares a position reference with a position feedback signal and sends
processing results to the Servopack as a speed reference.
In this way, the host controller can freely perform the control required for the servo mech-
anism.
The Servopack undertakes the speed control loop and subsequent control processing.
Yaskawa programmable machine controller PROGIC-8 is available as a typical host con-
troller.
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