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8.19.1.1
Characteristics of U/f control
Function description
The converter has different U/f characteristics.
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The voltage boost of the characteristic improves speed control at low speeds
②
With the flux current control (FCC), the converter compensates for the voltage drop in the stator
resistor of the motor
Figure 8-52
Characteristics of U/f control
With increasing speed or output frequency, the converter increases its output voltage U. The
maximum possible output voltage of the converter depends on the line voltage.
The converter can increase the output frequency even at the maximum output voltage. The
motor is then operated with field weakening.
Advanced commissioning
8.19 Motor control
Distributed converter for SIMOGEAR geared motors
Operating Instructions, 10/2020, FW V4.7 SP13, A5E31298649B AL
291