Omron SYSDRIVE RV Series User Manual page 253

Adjusting Slip Compensation Limit
The upper limit for the slip compensation amount can be set in C3-03 as a percent, taking the motor rated slip
amount as 100%.
If the speed is lower than the target value but does not change even when you adjust the slip compensation
gain, the motor may have reached the slip compensation limit. Increase the limit, and check the speed again.
Make the settings, however, to make sure that the value of the slip compensation limit and reference frequency
does not exceed the tolerance of the machine.
The following diagram shows the slip compensation limit for the constant torque range and fixed output range.
Slip compensation limit
Selecting Slip Compensation Function During Regeneration
Whether to enable or disable the slip compensation function during regeneration can be set in C3-04.
If the slip compensation function operates during regeneration, you might have to use the braking option
(braking resistor, Braking Resistor Unit, and Braking Unit) to momentarily increase the regenerative amount.
Selecting Output Voltage Limit Operation
If output voltage saturation occurs while the output voltage limit operation is disabled, the output current will
not change, but torque control accuracy will be lost. If torque control accuracy is required, set C3-05 to 1 to
enable the output voltage limit operation.
If the output voltage limit operation is enabled, motor magnetic flux current is controlled automatically, and
torque control accuracy is maintained to limit the output voltage references. Consequently, the output current
will increase by approximately 10% maximum (with rated load) compared with when the output voltage limit
operation is disabled, so check the Inverter current margin.
Setting Precautions
If using the device at medium to low speed only, if the power supply voltage is 10% or more higher than
•
the motor rated voltage, or if the torque control accuracy at high speeds is insufficient, it is not necessary to
change the output voltage limit operation.
If the power supply voltage is too low compared with the motor rated voltage, torque control accuracy may
•
be lost even if the output voltage limit operation is enabled.
E1-06: Base frequency
E1-04: Maximum output frequency
Fig 6.35 Slip Compensation Limit
Improved Operating Efficiency
Output frequency
45
6-