Mitsubishi MELDAS MDS-C1 Instruction Manual page 187

(4) Voltage non-sensitive zone (Td) compensation
With the PWM control of the inverter circuit, a dead time (non-energized time) is set to prevent
short-circuits caused by simultaneous energizing of the P side and N side transistors having the
same phase. The dead time has a non-sensitive zone for particularly low voltage commands. Thus,
when feeding with a low speed and a low torque, the control may be unstable.
When an unbalanced axis is lowering, the frictional torque and unbalance torque, and the frictional
torque and deceleration torque before the quadrant changes during circle cutting, are balanced.
The motor output torque will be approximately zero, and the control accuracy may drop. In this
case, the control accuracy can be improved by using the voltage non-sensitive band compensation.
Note that this may cause vibration to be increased while the motor is running.
Deceleration torque = frictional torque
For circle cutting
No. Abbrev. Parameter name
Voltage dead time
SV030 IVC
compensation
4. Servo Adjustment
Cutting direction
For unbalance torque
When 100% is set, the voltage equivalent to the logical non-energized time
will be compensated.
When "0" is set, a 100% compensation will be performed.
Adjust in increments of 10% from the default value 100%.
If increased too much, vibration or vibration noise may be generated.
4 - 16
.
Motor torque = 0
Frictional torque
Balanced
Unbalance torque
Lowering
Explanation
.
Setting range
0 to 200
(%)