5-41
F42
Control Mode Selection 1
F42 specifies the control mode of the inverter to control a motor.
Data for F42
Control mode
0
V/f control with slip compensation inactive
1
Dynamic torque vector control
2
V/f control with slip compensation active
11
V/f control for PMSM drive
V/f control
In this control, the inverter controls a motor by the voltage and frequency according to the V/f
pattern specified by function codes.
Slip compensation
Applying any load to an induction motor causes a rotational slip due to the motor
characteristics, decreasing the motor rotation. The inverter’s slip compensation facility first
presumes the slip value of the motor based on the motor torque generated and raises the
output frequency to compensate for the decrease in motor rotation. This prevents the motor
from decreasing the rotation due to the slip.
That is, this facility is effective for improving the motor speed control accuracy.
The compensation value is specified by combination of function codes P12 (Rated slip
frequency), P09 (Slip compensation gain for driving)) and P11 (Slip compensation gain for
braking).
Dynamic torque vector control
To get the maximal torque out of a motor, this control calculates the motor torque for the load
applied and uses it to optimize the voltage and current vector output.
Selecting this control automatically enables the auto torque boost and slip compensation
function and disables auto energy saving operation.
This control is effective for improving the system response against external disturbances and
the motor speed control accuracy.
V/f control for PMSM drive
Under this control, the inverter drives a permanent magnet synchronous motor (PMSM).
Refer to Section 5.3 "Notes in Driving PMSM" for details.
