Apparatus and method for sensorless identification of rotating electrical equivalent circuit parameters of a three-phase asynchronous motor

1α1β1α1β1α1β1α1βIdentification of electrical equivalent circuit parameters of a three-phase asynchronous motor without a shaft encoder. The method comprises-Assumption of a standstill position of the rotor;-Equidirectional test signal infeed U, U in α and β in the stator axis direction of the asynchronous motor;-Measuring of a measuring signal I, I of the α and β axial direction of the asynchronous motor; and-Identification of equivalent circuit parameters of the asynchronous motor on the basis of the test signal voltages U, U and of the measuring signal currents I, I; whereby the test signal feed allows the rotor to remain torque-free. Determination of equivalent circuit parameters of an asynchronous motor as well relates to a motor control device, whereby the identified equivalent circuit parameters can be used for the determination, optimization and monitoring of a motor control and for control of electrical drives.