To adapt to the specific requirements of various speed-controlled applications, OKE frequency converters are internally equipped with multiple V/F curves. This allows for suitable V/F curve settings for different applications, preventing malfunctions such as reduced machine efficiency and motor overheating, and improving the frequency-torque characteristics of the frequency converter to meet the requirements of different supporting equipment. The following is a brief introduction to the operating parameters of OKE frequency converters under different V/F curve settings and the principles of V/F curve setting.
P05.00 | V/F curve setting | 0: Straight line V/F curve 1: Multi-point V/F curve 2:1.2 power-law torque drop V/F curve 3:1.4 power-law torque drop V/F curve 4:1.6 power-law torque drop V/F curve 5:1.8 power-law torque drop V/F curve 6:2.0 power-law torque drop V/F curve | 0 |
When PO5.00=0, the V/F curve is linear. This is suitable for ordinary constant torque loads.
When PO5.00=1, the user-defined curve is suitable for segmented constant torque loads.
When PO5.00 = 2 to 5, the 1.2 to 1.8 power curves are applicable to other media types of liquid loads;
When PO5.00=6, the V/F curve is at the 2.0 power. Suitable for centrifugal loads such as fans and pumps.
Note : F1 ≤ F2 ≤ F3 ≤ Fb, V1 ≤ V2 ≤ V3 ≤ 100%
V/F curve diagram
For loads such as fans and pumps, the setting of the V/F curve is relatively complex. The following are some principles for setting the V/F curve for reference.
(1) When the load is running in the longest-term load area, the motor power factor should be moderate. If the power factor is too low, it means that the inverter output voltage is too high and the motor iron loss is large; if the power factor is too high, it means that the output voltage is too low, the motor copper loss is large and the overload capacity will be reduced.
(2) When the load is running in the highest load area, the motor current should not exceed the long-term operating current of the motor at this speed, nor should it exceed the rated current of the frequency converter.
(3) The motor temperature rise must not exceed the allowable value when the load is running in all load zones.
(4) It can meet the starting requirements.
