HV580L Series Frequency Inverter
97
10: VF complete separation. In this mode, the output frequency and output voltage of the AC drive are
independent. The output frequency is determined by the frequency source, and the output voltage is
determined by "Voltage source for VF separation" (P3-13).
It is applicable to induction heating, inverse power supply and torque motor control.
11: VF half separation
In this mode, V and F are proportional and the proportional relationship can be set in P3-13. The relationship
between V and F are also related to the rated motor voltage and rated motor frequency in Group P1.
Assume that the voltage source input is X (0 to 100%), the relationship between V and F is:
V/F = 2 x X x (Rated motor voltage) / (Rated motor frequency)
P3-01
Torque boost
Default
Model dependent
Setting Range
0.0%
~
30%
P3-02
Cut-off frequency of
torque boost
Default
50.00Hz
Setting Range
0.00Hz
~
maximum output frequency
To compensate the low frequency torque characteristics of V/F control, you can boost the output voltage of the
AC drive at low frequency by modifying P3-01. If the torque boost is set to too large, the motor may overheat,
and the AC drive may suffer over current.
If the load is large and the motor startup torque is insufficient, increase the value of P3-01.
If the load is small, decrease the value of P3-01. If it is set to 0.0, the AC drive performs automatic torque
boost. In this case, the AC drive automatically calculates the torque boost value based on motor parameters
including the stator resistance.
P3-02 specifies the frequency under which torque boost is valid. Torque boost becomes invalid when this
frequency is exceeded, as shown in the following figure 6-3.