Patent attributes
The present invention relates to a device for ascertaining the temperature TW of a winding of an induction machine designed with a stator and a rotor, comprising at least a first Kalman filter (K1) to calculate the temperature and a rotary field control for the vector control of the induction machine with at least one id-current controller, which is designed to impose a high-frequency voltage signal (HF) on the winding voltage in order to obtain from this a winding current with a superimposed high-frequency current component for the winding, which is taken to the Kalman filter (K1), the Kalman filter (K1) having a high-frequency model of the motor in order to determine from this the high-frequency resistance of the winding and in turn the winding temperature TW by means of a calculation function.