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9. Adjustment 
 
 
 
 
 
9 - 11
 
(3)  Adjusting the in-position width 
Because there is a response delay in the servomotor drive due to position loop control, a "settling 
time" is also required for the motor to actually stop after the command speed from the CNC reaches 0. 
The movement command in the next block is generally started after it is confirmed that the machine 
has entered the "in-position width" range set for the machine. 
Set the precision required for the machine as the in-position width. If a high precision is set 
needlessly, the cycle time will increase due to a delay in the settling time. 
As a standard, the in-position width is valid with the servo parameters. However, there may be 
cases when the NC parameters must be set. Refer to each NC Instruction Manual and set the 
value. 
 
No. 
Abbrev. 
Parameter name 
Explanation 
Setting range
SV024 INP In-position 
detection 
width 
Set the in-position detection width.  
Set the accuracy required for the machine. 
The lower the setting is, the higher the positioning accuracy gets, 
however, the cycle time (setting time) becomes longer. The standard 
setting is "50". 
0 to 32767 
(
m) 
 
 
 
POINT
 
The in-position width setting and confirmation availability depend on the CNC 
parameters. 
 
 
(4)  Adjusting the settling time 
The settling time is the time required for 
the position droop to enter the in-position 
width after the feed command (F
∆T) from 
the CNC reaches 0.  
The settling time can be shortened by 
raising the position loop gain or using SHG 
control. However, a sufficient response 
(sufficiently large VGN1 setting) for the 
speed loop is required to carry out stable 
control. 
The settling time during normal control 
when the CNC is set to linear acceleration/ 
deceleration can be calculated using the 
following equation. During SHG control, 
estimate the settling time by multiplying 
PGN1 by    2 .  
 
 
 
 
PGN1 : Position loop gain1 (SV003) 
(rad/s) 
: Rapid traverse rate 
(mm/min) 
G0tL  : Rapid traverse linear acceleration/  
 
  deceleration time constant 
(ms) 
INP  : In-position width (SV024) 
(
m) 
Settling time (ms) = –
 
×
PGN1
 
10
3
 
INP
F × 10
6
60×G0tL×PGN1
2
×
1 -  exp
 
PGN1×G0tL
10
3
ln 
0
0
F
∆T 
Position 
droop 
F
Time
Settling time 
G0tL
In-position 
In-position width