Method and apparatus for estimating angles in a synchronous machine

An apparatus for estimating angles in a synchronous machine, the apparatus comprising:

• an angle sensor device which is designed to determine event-discrete measured values for a rotor angle of a rotor of the synchronous machine and to output a measurement signal dependent on the determined measured values;
• an estimation device which is designed to record current and/or voltage signals from the synchronous machine, to calculate a deviation of the rotor angle of the rotor of the synchronous machine from an expected rotor angle on the basis of the recorded current and/or voltage signals and to output a deviation signal dependent on the calculated deviation;
• and
• a combining device which is designed to receive the measurement signal and the deviation signal and to calculate an estimated value for the rotor angle of the rotor of the synchronous machine from a combination of the measurement signal and the deviation signal
• wherein the combining device includes a Kalman filter or an observer structure which has a prediction device, which is designed to calculate a prediction value for the state vector of a dynamic model of the rotor, and a correction device which is designed to calculate a correction signal on the basis of the prediction value.