Servo Rigidity Adjustment; Delay/Advance Control And Pi Control - Mitsubishi Electric MDS-B-SPJ2 Series Specification Manual

8.5.4 Servo rigidity adjustment

Increase the servo rigidity during orientation stop by adjusting with the following procedure.
i) Increase the PGM (motor built-in encoder orientation, magnesensor orientation) and PGE
(encoder orientation) values to a level where swaying does not occur at the orientation stop.
ii) Raise the values of parameters VGOP and VGOI by the same percentage.
For example, if VGOP is set to 80, also set VGOI to 80.
Note that the magnification cannot be raised further if vibration occurs during orientation stop at
this setting.
iii) Parameter VGOD is the delay/advance compensation gain.
The servo rigidity can be momentarily raised by increasing this value, but the torque for the
position error will drop.
PI control is validated at orientation stop when VGOD = 0.

8.5.5 Delay/advance control and PI control

Delay advance control is normally selected. Use PI control in the following case.
• When the spindle static friction torque is large, and machine PI control is required for stop position
accuracy, the servo rigidity will drop somewhat compared with delay/advance control, so select
this control matching the machine specifications.
8. Adjustment Procedure
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