8.13 Manual Tuning
8.13.1 Tuning the Servo Gains
8-84
The block diagram for model following control is provided below.
Manual Tuning Procedure
Use the following tuning procedure for using model following control.
Related Parameters
Next we will describe the following parameters that are used for model following control.
•
Pn140 (Model Following Control-Related Selections)
•
Pn141 (Model Following Control Gain)
•
Pn143 (Model Following Control Bias in the Forward Direction)
•
Pn144 (Model Following Control Bias in the Reverse Direction)
•
Pn147 (Model Following Control Speed Feedforward Compensation)
Model Following Control-Related Selections
Set Pn140 = n.
X to specify whether to use model following control.
If you use model following control with vibration suppression, set Pn140 to n.
1
or Pn140
= n.
2
. When you also perform vibration suppression, adjust vibration suppression with
custom tuning in advance.
Note: If you use vibration suppression (Pn140 = n.
1
or Pn140 = n.
2
), always set Pn140 to n.
1
(Use model following control).
Step
Description
1
Friction compensation must also be used. Set the friction compensation parameters. Refer to the
following section for the setting procedure.
2
Adjust the servo gains. Refer to the following section for an example procedure.
Tuning Procedure Example (for Position Control or Speed Control)
Note: 1. Set the moment of inertia ratio (Pn103) as accurately as possible.
2. Refer to the guidelines for manually tuning the servo gains and set a stable gain for the position loop gain
(Pn102).
Guidelines for Manually Tuning Servo Gains
3
Increase the model following control gain (Pn141) as much as possible within the range in which
overshooting and vibration do not occur.
4
If overshooting occurs or if the response is different for forward and reverse operation, fine-tune
model following control with the following settings: model following control bias in the forward direc-
tion (Pn143), model following control bias in the reverse direction (Pn144), and model following con-
trol speed feedforward compensation (Pn147).
Model following
control
mKp, mVFF, mTFF
+
M
PG
+
+
Tf
Speed
Speed pattern
Time
Movement
reference
Torque feedforward
Speed control loop
Servomotor
Power
converter
Current
control
section
Speed loop
Speed control
section
Kv and Ti
Speed
reference
Position
loop gain
Kp
Deviation
counter
Position loop
SERVOPACK
Host controller
(Not provided by Yaskawa)
Current loop
Encoder
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)
mKp: Model following control gain (Pn141)
Speed
feedforward
mTFF: Model following control bias in the forward direction (Pn143)
Model following control bias in the reverse direction (Pn144)
mVFF: Model following control speed feedforward compensation (Pn147)
Position control loop