Summa Series Servodrive Product Manual
Tuning
Document Version: V1.01
(Dec, 2019)
© 2019 ESTUN Automation Co., Ltd. All right reserved.
9-31
Parameter Setting
Meaning
When Enabled Classification
3
Use the speed reference as the
condition (threshold setting: Pn120).
4
Fixed to PI Control.
Set Pn116 to 4 (Fixed to PI Control), indicating that the Proportional-Integral Controller is always
used.
Set Pn116 as 0 to 3, indicating that switch to Proportional Controller when the switching condition
exceeds the set threshold value, otherwise the Proportional-Integral Controller is used.
The relevant threshold parameters are shown in the table below.
Parameter Setting
Meaning
When Enabled Classification
Pn117
－
Torque Reference Threshold for P/PI
Switch
Immediately
Adjustment
Pn118
－
Deviation Counter Threshold for P/PI
Switch
Immediately
Adjustment
Pn119
－
Acceleration Reference Threshold for
P/PI Switch
Immediately
Adjustment
Pn120
－
Speed Reference Threshold for P/PI
Switch
Immediately
Adjustment
Take the default settings as an example, the default setting of Pn116 is
0
(Use torque reference as the
condition), and the default Torque Reference Threshold for P/PI Switch (Pn117) is 200, in this case, when
the torque reference percentage exceeds 200, the speed loop adjustment will be switched from PI control
to P control, and then if the torque reference percentage is not more than 200, the speed loop adjustment
is switched to PI control.
9.5.3
Feedforward
Feedforward includes speed feedforward and torque feedforward.
Speed feedforward can improve position response and reduce position following error
Torque feedforward can improve the speed response and reduce the speed following error
Figure 9-14 shows the block diagram in the feedforward function.
Figure 9-14
Feedforward block diagram
Drive
Position loop
Speed loop
Torque loop
Position
reference
M
Current
Encoder
Motor
Speed
Position
Host
Controller
Speed feedforward
Torque feedforward
In general, the differential of the position reference is used as the feedforward, you can also set the feed
forward by the controller or other application functions.
You can set Pn005 to select the method for the feedforward.
