Patent ID: 7746039

Claim:
A method for applying a controlled stator current set point value and a controlled torque set point value to a converter-fed rotating-field machine, comprising: computing a field-forming current component of the stator current set point value as a function of a predetermined rotor flux set point value and a measured actual rotor flux value; computing a torque-forming current component of the stator current set point value as a function of a predetermined torque set point value, the measured actual rotor flux value and a measured torque-forming current component of a measured stator current; determining an actual stator angular frequency value as a function of a measured rotor slip frequency and of an angular frequency; by using a frequency-dependent stray inductance and a stator resistance as parameters, computing the integral the stator voltage as a manipulated variable from the computed values of the field-forming current component, the torque-forming current component, the actual stator angular frequency, and the measured rotor slip frequency; and deriving from the integral of the stator voltage a flux path curve which is selected from optimized flux path curves stored off-line.