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2: square V / F. Suitable for fans, pumps and other centrifugal load.
3 ~ 8: between the linear VF and square VF VF relationship between the curve.
10: VF complete separation mode. At this time the output frequency of the
inverter and the output voltage are independent of each other, the output
frequency is determined by the frequency source, and the output voltage is
determined by P3-13 (VF separation voltage source).
VL complete separation mode, the general application of induction heating,
inverter power supply, torque motor control and other occasions.
11
：
VF Semi-separation mode.
In this case V and F are proportional, but the proportional relationship can be set by the
voltage source P3-13, and the relationship between V and F is also related to the rated
voltage of the motor of P1 group and the rated frequency.
Assuming that the voltage source input is X (X is a value of 0 to 100%), the relationship
between the inverter output voltage V and the frequency F is:
V / F = 2 * X * (motor rated voltage) / (motor rated frequency)
P3-01
Torque boost
Factory default
Motor ensure
Set range
0.0%
～
30%
P3-02
Torque boost cutoff
frequency
Factory default
50.00Hz
Set range
0.00Hz
～
max output frequency
In order to compensate for the V / F control low frequency torque characteristics, the low
frequency inverter output voltage to do some lifting compensation. But the torque boost
setting is too large, the motor is easy to overheat, the inverter is easy to overcurrent.
It is recommended to increase this parameter when the load is heavy and the motor starting
torque is not enough. The torque boost can be reduced when the load is light.
When the torque boost is set to 0.0, the inverter will be automatically boosted, and the
inverter will automatically calculate the required torque boost according to the parameters
such as motor stator resistance.
Torque boost torque cutoff frequency: Under this frequency, the torque boost torque is
valid, beyond this set frequency, torque boost failure, as shown in Figure 6-5.
Figure 6-5 Manual torque boost diagram
