5-2 V/f Control Settings
5-2-1 Control Method (V/f Characteristics)
•
V/f control is a method of controlling a motor by setting the output voltage and frequency of the
inverter as V/f characteristics, which is effective for using the inverter easily.
•
To set V/f characteristics (output voltage and output frequency), set the 1st/2nd Control Method to 00
to 02.
*1. Sensorless vector control can be set in the heavy load mode only. For details on sensorless vector control,
refer to 6-1 Sensorless Vector Control on page 6-3.
*2. Setting the Inverter Mode Selection (b171) to 03 (PM motor mode) does not cause the parameters
A044/A244 to be displayed after initialization.
*3. To enable the switching to the 2nd control, allocate one of the Multi-function Input
1 to 7 Selection (C001 to
C007) to 08 (SET) and then turn ON that terminal.
This setting is suitable for cart, conveyor, overhead traveling crane, and other applications where a
torque is required, independent of the motor rotation speed.
It enables the output of a constant torque based on the frequency, according to the V/f characteristics
that represent the proportional relationship between the output frequency and the output voltage.
However, the output voltage is proportional from 0 Hz to the base frequency, it is constant independent
of the frequency, from the base frequency to the maximum frequency.
For the base frequency, set the rated frequency of the motor.
For the maximum frequency, set the highest frequency required for your application, within the maxi-
mum frequency of the motor.
Output
voltage
(100%)
0
Base
Frequency
Output frequency
[Hz]
Maximum Frequency