Mitsubishi Electric MDS-E, Instruction Manual

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MDS-E/EH Series Instruction Manual
5 Servo Adjustment
257 IB-1501229-F
Shape error characteristics
During SHG control, PGN1, PGN2 and SHGC are set with the following ratio.
PGN1 : PGN2 : SHGC = 1 : 8/3 : 6
During SHG control even if the PGN1 setting value is the same, the actual position loop gain will be higher, so the
speed loop must have a sufficient response. If the speed loop response is low, vibration or overshooting could occur
during acceleration/deceleration in the same manner as conventional control. If the speed loop gain has been
lowered because machine resonance occurs, lower the position loop gain and adjust.
【 #2208 】 SV008 VIA Speed loop lead compensation
Set the gain of the speed loop integral control.
Standard setting: 1364
Standard setting in the SHG control: 1900
Adjust the value by increasing/decreasing this by about 100 at a time.
Raise this value to improve contour tracking accuracy in high-speed cutting.
Lower this value when the position droop does not stabilize (when the vibration of 10 to 20Hz
occurs).
---Setting range---
1 to 9999
【
#2215
】
SV015 FFC Acceleration rate feed forward gain
When a relative error in synchronous control is too large, set this parameter to the axis that is
delaying.
The standard setting is "0". The standard setting in the SHG control is "100".
To adjust a relative error in acceleration/deceleration, increase the value by 50 at a time.
---Setting range---
0 to 999 (%)
No. Abbrev. Parameter name
Setting
ratio
Setting example Explanation
Setting
range
SV003
(SV049)
PGN1
(PGN1sp)
Position loop gain 1 1 21 27 33 39 48
Always set with a combination
of these three parameters.
1 to 200
(rad/s)
SV004
(SV050)
PGN2
(PGN2sp)
Position loop gain 2 8/3 56 72 88 104 128
0 to 999
(rad/s)
SV057
(SV058)
SHGC
(SHGCsp)
SHG control gain 6 126 162 198 234 288
0 to 1200
(rad/s)
(F=3000mm/min , ERROR=5.0μm/div )
-50.0 50.0 0.0
0.0
-50.0
50.0
[1] : Commanded path
[2] : SHG control (PGN1=47)
[3] : Conventional control (PGN1=33)
Conventional
control
SHG control
Control
method
Roundness error ( ȣ m)
2.5
22.5
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