Omron R88D-KTA5L User Manual page 428

6-17 Instantaneous Speed Observer Function
Operating Procedure
1. Set the Inertia Ratio (Pn004).
Set the inertia ratio as correctly as possible.
 If the Inertia Ratio (Pn004) is requested in a realtime auto gain tuning, use the set value.
 If the inertia ratio is calculated for the selected motor, input the calculated value.
 If the inertia ratio is not known, perform autotuning and set the inertia ratio.
2. Adjust the position loop gain and speed loop gain.
Adjust Position Loop Gain (Pn100), Speed Loop Gain (Pn101), Speed Loop Integral Time
Constant (Pn102) and Torque Command Filter Time Constant (Pn104).
If no problem occurs in realtime autotuning, you can continue to use the settings.
3. Set the Function Expansion Setting (Pn610).
Set whether to enable or disable the instantaneous speed observer function in bit 0.
0: Disabled
1: Enabled
If you set this to 1 (enabled), the speed detection method will switch to instantaneous speed
observer.
 If the machine operation noise or vibration, or a change in the torque monitor waveform is
significant enough to cause any problem, return the setting to 0 and make sure that the inertia ratio
or the adjustment parameters are correct.
6
 If the machine operation noise or vibration, or a change in the torque monitor waveform is small,
make small adjustments to the Inertia Ratio (Pn004) to find the setting that makes the smallest
change while monitoring the position error waveform and the actual speed waveform.
 If Position Loop Gain (Pn100), Speed Loop Gain (Pn101) or Speed Loop Integral Time Constant
(Pn102) is changed, the optimal value for the Inertia Ratio (Pn004) may have changed, so make
small adjustments on the value for the Inertia Ratio (Pn004) again to set a value that makes the
smallest change.
 This function may not function properly or the effect may not be apparent under the following
conditions.
6-56
Precautions for Correct Use
· If the margin of error with the actual device is large for the inertia load
· If there are multiple resonance points
· If there is a large resonance point at a frequency of 300 Hz or lower
· If there is a non-linear element (play), such as a large backlash
· If the load inertia changes
· If there is a large disturbance torque with high-frequency elements is applied
· If the setting range for positioning is small
OMNUC G5-SERIES AC SERVOMOTOR AND SERVO DRIVE USER'S MANUAL