Omron G5 R88D-KE Series, User Manual

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7 Parameter Details
7 - 10
OMNUC G5-series (Pulse-train Input Type) AC Servomotors and Servo Drives User’s Manual
7-2 Gain Parameters
*1 The default setting is 320 for a Servo Drive with 200 V and 1 kW or more.
• Adjust 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 400
(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 mechanical resonance, resulting in an overload alarm.
• If the position loop gain is low, you can shorten the positioning time using feed-forward.
• This parameter is automatically changed by the realtime autotuning function. For manual adjustment,
set Realtime Autotuning Mode Selection (Pn002) 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 delays 2/Kp for
acceleration and 3/Kp for deceleration in response to command input.
Pn100
Position Loop Gain
Setting
range
0 to 30,000 Unit 0.1/s Default
setting
480
*1 Cycle the
power supply
–
Position
Position loop gain (Kp) =
Command pulse frequency (pulses/s)
No. of error pulses accumulated in error counter
(0.1/s)
Motor speed
Time
Position loop gain is high
Position loop gain is low
Kp
3
Kp
2
Motor speed
Time
Position
command
Motor operation