Parameter
Number Name Factory setting
p0010 Drive commissioning parameter lter 1
p0230 Drive lter type, motor side 0
p0235 Number of motor reactors in series 1
p0350[M] Motor stator resistance, cold 0Ω
p0352[M] Cable resistance 0Ω
For further information on parameters, please refer to the parameter list.
8.20.2 U/f control
8.20.2.1 U/f control
Overview
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In the "Flux Current Control (FCC)" U/f version, the converter controls the motor current (starting
current) at low speeds.
Figure8-46 Simplied function diagram of the U/f control
The U/f control is a speed feedforward control with the following properties:
• The converter sets the output voltage on the basis of the U/f characteristic.
• The output frequency is essentially calculated from the speed setpoint and the number of
pole pairs of the motor.
• The slip compensation corrects the output frequency depending on the load and thus
increases the speed accuracy.
• The omission of a control loop means that the U/f control is stable in all cases.
• In applications with higher speed accuracy requirements, a load-dependent voltage boost
can be selected (ux current control, FCC)
For operation of the motor with U/f control, you must set at least the following subfunctions
appropriate for your application:
• U/f characteristic
• Voltage boost
Advanced commissioning
8.20Motor control
SINAMICS G120C Converters
300 Operating Instructions, 02/2023, FW V4.7 SP14, A5E34263257B AK