9 - 7
9 Servo Parameter Objects
G5-series Linear Motors/Servo Drives With Built-in EtherCAT Communications
9-2 Gain
Setti
ngs
9
9-2
Gain Settings
Refer to 11-2 Gain Adjustment on page 11-5 for the settings for gain adjustment.
*1
The default setting is 320 for a Drive with 200 V and 1 kW or greater, or with 400 V.
•
Set the position loop response in accordance with the machine rigidity.
•
The responsiveness of the servo system is determined by the position loop gain.
•
Servo systems with a high position loop gain have a high responsiveness and fast positioning.
•
To increase the position loop gain, you must improve machine rigidity and increase the specific
damping frequency. This should be 500 to 700 [0.1/s] for ordinary machine tools, 300 to 500 [0.1/s]
for general-use and assembly machines, and 100 to 300 [0.1/s] for industrial robots. The default
position loop gain is 480 [0.1/s], so be sure to lower the set value for machines with low machine
rigidity.
•
Increasing the position loop gain in systems with low machine rigidity or systems with low specific
damping frequencies may cause machine resonance, resulting in an overload error.
•
If the position loop gain is low, you can shorten the positioning time using feed-forward.
•
This object is automatically changed by executing realtime autotuning function. To set it manually,
set the Realtime Autotuning Mode Selection (3002 hex) to 0.
Position loop gain is generally expressed as follows:
Response for Position Loop Gain Changes
•
If the speed loop gain and position loop gain are
optimally set, the motor operation for the command
delays 2/Kp at acceleration and delays 3/Kp at
deceleration.
3100 hex
Position Loop Gain 1
Setting
range
0 to 30,000
Unit
0.1/s
Default
setting
480
*1
Data
attribute
B
Size
2 bytes (INT16)
Access
RW
PDO map
Not possible
csp
pp
hm
[0.1/s]
Command pulse frequency [Pulse/s]
Pulse position error [Pulse]
Position loop gain [Kp] =
Motor speed
Time
Position loop gain is high.
Position loop gain is low.
Kp
3
Kp
2
Motor speed
Time
Position
command
Motor
operation
