YASKAWA CIMR-VU BA0001 Technical Manual page 153

Torque Compensation in V/f Control:
The drive calculates the motor primary voltage loss using the output current and the terminal resistance value (E2-05) and
then adjusts the output voltage to compensate insufficient torque at start or when load is applied. The effect of this voltage
compensation can be increased or decreased using parameter C4-01.
Torque Compensation in Open Loop Vector Control:
The drive controls the motor excitation current and torque producing current separately. Torque compensation affects the
torque producing current only. C4-01 works as a factor of the torque reference value that builds the torque producing current
reference.
Adjustment
Although this parameter rarely needs to be adjusted, small changes in increments of 0.05 may help in the following situations:
• Increase this setting when using a long motor cable.
• Decrease this setting when motor oscillation occurs.
Adjust C4-01 so that the output current does not exceed the drive rated current.
n C4-02: Torque Compensation Primary Delay Time 1
Sets the delay time used for applying torque compensation.
No.
C4-02
Adjustment
Although C4-02 rarely needs to be changed, adjustments may help in the following situations:
• If the motor vibrates, increase C4-02.
• If the motor responds too slowly to changes in the load, decrease C4-02.
n C4-03: Torque Compensation at Forward Start (OLV only)
Sets the amount of torque at start in the forward direction in order to improve motor performance during start with heavy load.
Compensation is applied using the time constant set in parameter C4-05. A setting of 0.0% disables this feature.
No.
C4-03
n C4-04: Torque Compensation at Reverse Start (OLV only)
Sets the amount of torque reference at start in the reverse direction in order to improve motor performance during start with
heavy load. Compensation is applied using the time constant set in parameter C4-05. A setting of 0.0% disables this feature.
No.
C4-04
n C4-05: Torque Compensation at Start Time Constant (OLV only)
This parameter is the time constant for applying the torque compensation at start set in parameters C4-03 and C4-04.
No.
C4-05
n C4-06: Torque Compensation Primary Delay Time 2 (OLV only)
This time constant is used during Speed Search or during regenerative operation when the actual motor slip is higher than 50%
of the rated slip. Adjust the value if an overvoltage fault occurs with sudden changes in the load or at the end of acceleration
with high inertia load.
No.
C4-06
Note: 1. If C4-06 is set to a relatively large value, be sure to also increase the setting in n2-03 (AFR Time Constant 2) proportionally.
2. C4-06 will not be active if L3-04 is 0, 3 or 4, the output frequency is below 5 Hz, or Speed Search after momentary power loss is active.
YASKAWA ELECTRIC SIEP C710606 18F YASKAWA AC Drive – V1000 Technical Manual
Parameter Name
Torque Compensation Primary Delay Time 1
Parameter Name
Torque Compensation at Forward Start
Parameter Name
Torque Compensation at Reverse Start
Parameter Name
Torque Compensation Time Constant
Parameter Name
Torque Compensation Primary Delay Time 2
5.3 C: Tuning
Setting Range
Determined by
0 to 60000 ms
Setting Range
0.0 to 200.0%
Setting Range
-200.0 to 0.0%
Setting Range
0 to 200 ms
Setting Range
0 to 10000 ms
Default
A1-02
Default
0.0%
Default
0.0%
5
Default
10 ms
Default
150 ms
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