Mitsubishi MELDAS HS Series Specifications And Instruction Manual page 94

(3) Inductive voltage compensation
The current loop response is improved by compensating the back electromotive force element
induced by the motor rotation. This improved the current command efficiency, and allows the
acceleration/deceleration time constant to the shortened.
<Adjustment method>
1) Set 1 in "mon" of the special servo function selection 3 (SV034: SSF3) bit 0, and output the
current command and current FB to the servo monitor.
2) While accelerating/decelerating at rapid traverse, adjust the inductive voltage compensation
gain (SV047:EC) so that the current FB peak is a few % smaller than the current command
peak.
3000
Speed
command
(r/min)
-3000
200
Current
command
(stall %)
-200
To adjust the inductive voltage compensation, output 1 second of the maximum current
command value and 1 second of the maximum current FB value to MAX current 1 and MAX
current 2 on the CNC servo monitor screen and observe.
Change over and display "mon" of the special servo function selection 3 (SV034: SSF3).
No. Abbrev. Parameter name
SV034 SSF3 Special servo function
selection 3
No. Abbrev. Parameter name
Inductive voltage
SV047 EC
compensation gain
POINT
Chapter 8 Adjustment
0
No inductive voltage
compensation
0
With inductive
voltage
compensation
Inductive voltage compensation
The display data for the maximum current value on the servo monitor is determined
with the following parameter.
15 14
bit
0 mon
Unit
Set 100% as a standard. Lower the gain if the current FB peak
%
exceeds the current command peak.
If the current FB peak is larger than the current command peak,
overcompensation or overcurrent (alarm 3A) could occur easily. Note that
when using with a large load inertia, or when using over the rated rotation
speed with a motor set to rated rotation speed < maximum rotation speed,
overcompensation could occur easily.
Explanation
13 12 11 10 9 8
Monitor Meaning when 0 is set
Maximum current command
MAX
value after power is turned
current 1
ON
Maximum current
MAX
com-mand value for one
current 2
second
Explanation
8–27
Time
Time
7 6 5 4 3 2
daf1 dac1
Meaning when 1 is set
Maximum current command
value for one second
Maximum current FB value
for one second
Setting range
0 to 200
1 0
mon