Sourcetronic ST600 - Page 72

Frequency Inverter ST600 Series High-Performance Multifunction VFD Basic Operation Instructions
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b
f
b
V
Output voltage
Output frequency
Straight-type
Torque -down V/F curve (power of 1.3)
Square-type
Torque -down V/F curve (power of 1.7)
Torque -down V/F curve (power of 2.0)
The VFD also provides multi-point V/F curve. Users can alter the V/F curve outputted by VFD through
setting the voltage and frequency of the three points in the middle. The whole curve consists of five
points starting from (0Hz, 0V) and ending in (fundamental motor frequency, rated motor voltage).
During setup, it is required that 0≤f1≤f2≤f3≤fundamental motor frequency, and 0≤V1≤V2≤V3≤rated
motor voltage
b
f
Output voltage
f1
f2
f3
V1
V2
V3
Output frequency
Hz
b
V%100
The VFD provides dedicated function codes for SVPWM control mode. Users can improve the
performance of SVPWM through settings.
1. Torque boost
Torque boost function can effectively compensate for the low-speed torque performance during
SVPWM control. Automatic torque boost has been set by default to enable the VFD to adjust the
torque boost value based on actual load conditions.
Note:
(1) Torque boost is effective only under torque boost cut-off frequency;
(2) If the torque boost is too large, low-frequency vibration or overcurrent may occur to the motor, if
such situation occurs, lower the torque boost value.