12.2
Functions and configuration
Outline
Either a semi closed loop system or a fully closed loop system can be selected as a control method for this servo amplifier.
In addition, the semi closed loop control, fully closed loop control, or dual feedback control can be selected by the setting of
[Pr. PE08 Fully closed loop dual feedback filter] in the fully closed loop system.
Fully closed loop operation mode selection
Servo amplifier
(Refer to "■Selecting operation mode")
The following table lists the characteristics of each control method.
Control
Semi closed loop control
Dual feedback control
Fully closed loop control
12 USING A FULLY CLOSED LOOP SYSTEM
446
12.2 Functions and configuration
([Pr. PA01.4])
"0"
"1"
Fully closed loop
function selection
([Pr. PE01.0])
(Refer to "■Selecting semi closed/
fully closed loop control")
Description
Feature
The position is controlled with servo motor-side information.
Advantage
Because this control method is not susceptible to machine resonance, it can increase the gain of the servo
amplifier and shorten the settling time.
Disadvantage
Even when the servo motor side is stopped, the load side may vibrate or accuracy at the load side may not be
achieved.
Feature
The position is controlled with servo motor-side information and load-side information.
Advantage
The gain during operation can be increased and thus the settling time can be shorten by switching the
information type to control the position as follows: the servo motor-side information during operation and the
load-side information during stops.
When the servo motor stops, it stops with the accuracy at the load side.
Feature
The position is controlled with load-side information.
Advantage
Accuracy at the load side is achieved not only during stops, but also during operation.
Disadvantage
Because this control method is susceptible to machine resonance, it may be unable to increase the gain of the
servo amplifier.
Semi closed/fully closed loop switching command
OFF
ON
Fully closed loop dual
"1"
feedback filter
([Pr. PE08])
"0"
Semi closed loop system
Semi closed loop control
Fully closed loop system
Semi closed loop control
"1 to 4499"
Dual feedback control
"4500"
Fully closed loop control