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MDS-D2/DH2 Series Instruction Manual
5.2 Gain Adjustment
(2) Setting the position loop gain for spindle synchronous control
During spindle synchronous control (synchronous tapping control, etc.), there are three sets of position loop gain
parameters besides the normal control.
【#2249】 SV049 PGN1sp Position loop gain 1 in spindle synchronous control
Set the position loop gain during spindle synchronization control (synchronous tapping and
synchronization control with spindle C-axis).
Set the same value as that of the position loop gain for spindle synchronous tapping control.
When performing the SHG control, set this parameter with SV050 (PGN2sp) and SV058 (SHGCsp).
---Setting range---
1 to 200 (rad/s)
【#2250】 SV050 PGN2sp Position loop gain 2 in spindle synchronous control
When using SHG control during spindle synchronous control (synchronous tapping and
synchronization control with spindle C-axis), set this parameter with SV049 (PGN1sp) and SV058
(SHGCsp).
Make sure to set the value 8/3 times that of SV049.
When not using the SHG control, set to "0".
---Setting range---
0 to 999 (rad/s)
【#2258】 SV058 SHGCsp SHG control gain in spindle synchronous control
When using SHG control during spindle synchronization control (synchronous tapping and
synchronous control with spindle C-axis), set this parameter with SV049 (PGN1sp) and SV050
(PGN2sp).
Make sure to set the value 6 times that of SV049.
When not using the SHG control, set to "0".
---Setting range---
0 to 1200 (rad/s)
(3) SHG control
If the position loop gain is increased or feed forward control (NC function) is used to shorten the settling time or
increase the precision, the machine system may vibrate easily.
SHG control changes the position loop to a high-gain by stably compensating the servo system position loop
through a delay. This allows the settling time to be reduced and a high precision to be achieved. (SHG: Smooth
High-Gain)
(Feature 1) When the SHG control is set, even if PGN1 is set to the same value as the conventional gain, the
position loop gain will be doubled.
(Feature 2) The SHG control response is smoother than conventional position control during acceleration/
deceleration, so the gain can be increased further with SHG control compared to the conventional
position control.
(Feature 3)With SHG control, a high gain is achieved so a high precision can be obtained during contour control.
The following drawing shows an example of the improvement in roundness characteristics with SHG
control.
CAUTION
Always set the same value for the position loop gain between the spindle and servo synchronous axes.
