➢ When the VF curve is straight line and power curve, the frequency-voltage curve is as follows:
!
Figure 1:Straight line VF and 1.3、1.7、2.0 power VF
➢
Multi-stage line type VF curve:
Figure 2:Ø multi-stage line type VF curve
➢ VF full separation
The output voltage and output frequency are completely independent. The output frequency is determined by
the frequency source. The output voltage is determined by P12.20. Suitable for applications such as variable
frequency power or torque motors.
➢ VF semi-isolated
At this point the ratio of output voltage and output frequency given by the voltage source, the formula is as
follows::