Manual Tuning; Tuning The Servo Gains - YASKAWA SGD7S Product Manual

8.13

Manual Tuning

This section describes manual tuning.
8.13.1

Tuning the Servo Gains

Servo Gains
Speed
Speed pattern Movement
DeviceNet Module
In order to manually tune the servo gains, you must understand the configuration and charac-
teristic of the SERVOPACK and adjust the servo gains individually. In most cases, if you greatly
change any one parameter, you must adjust the other parameters again. To check the
response characteristic, you must prepare a measuring instrument to monitor the output wave-
forms from the analog monitor.
The SERVOPACK has three feedback systems (the position loop, speed loop, and current
loop), and the response characteristic must be increased more with the inner loops. If this rela-
tionship is not maintained, the response characteristic will suffer and vibration will occur more
easily.
A sufficient response characteristic is ensured for the current loop. There is never a need for it
to be adjusted by the user.
Outline
You can use manual tuning to set the servo gains in the SERVOPACK to increase the response
characteristic of the SERVOPACK and to reduce the positioning time.
Use manual tuning in the following cases.
• When tuning with autotuning without a host reference or autotuning with a host reference
does not achieve the desired results
• When you want to increase the servo gains higher than the gains that resulted from autotun-
ing without a host reference or autotuning with a host reference
• When you want to determine the servo gains and moment of inertia ratio yourself
You start manual tuning either from the default parameter settings or from the gain settings that
resulted from autotuning without a host reference or autotuning with a host reference.
Position control loop
reference
+
Deviation
Position

counter
loop gain Kp
Time
Position loop
Speed control loop
Speed
reference
+
Speed control
Tf

section
Kv and Ti
Speed loop
SERVOPACK
Kp: Position loop gain (Pn102)
Kv: Speed loop gain (Pn100)
Ti: Speed loop integral time constant (Pn101)
Tf: First stage first torque reference filter time constant (Pn401)

8.13 Manual Tuning

8.13.1 Tuning the Servo Gains

Servomotor
+
Current
M
Power

control
converter
section
Current loop
PG
Encoder
8
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