YASKAWA SGD7S Product Manual page 326

The block diagram for model following control is provided below.
Speed
Movement
Speed pattern
reference
mKp, mVFF, mTFF
Time
Position control loop
+
Deviation

counter
Position loop
DeviceNet Module
 Manual Tuning Procedure
Use the following tuning procedure for using model following control.
Step
Friction compensation must also be used. Set the friction compensation parameters. Refer to the
1 following section for the setting procedure.
8.12.2 Friction Compensation on page 8-69
Adjust the servo gains. Refer to the following section for an example procedure.
Tuning Procedure Example on page 8-78
Note: 1. Set the moment of inertia ratio (Pn103) as accurately as possible.
2
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 on page 8-83
Increase the model following control gain (Pn141) as much as possible within the range in which
3
overshooting and vibration do not occur.
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-
4
tion (Pn143), model following control bias in the reverse direction (Pn144), and model following con-
trol speed feedforward compensation (Pn147).
 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).
Model following
control
Speed
feedforward
Speed control loop
Speed
reference +
Position Speed control

loop gain
section
Kp
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)
mKp: Model following control gain (Pn141)
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)
Description
8.13 Manual Tuning
8.13.1 Tuning the Servo Gains
Torque feedforward
Servomotor
+
Current
Tf
Power

control
converter
section
Current loop
Encoder
M
PG
8
8-85