Electric drive unit, method for operating an electric drive unit and method for calculating temperature

A method for calculating a temperature of an electric drive unit, comprising:

• providing:
• a temperature model describing a system context of the electric drive unit via a state space model;
• a system observer;
• and
• a temperature detection element;
• calculating a temperature model output variable (ym) using an input variable (u) and the temperature model;
• assigning the temperature model output variable (ym) to the system observer;
• measuring an actual temperature (y) corresponding to the input variable (u) at a measuring position of the electric drive unit using the temperature detection element;
• regulating and outputting a model state variable (xm) of the system context based on an output variable difference (Δy) between the actual temperature (y) and the temperature model output variable (ym) using the system observer;
• indicating a fault mode or a normal mode of the temperature detection element using a detection state signal (s1);
• and
• depending on the detection state signal (s1), switching the system observer between:
• a control mode, in which the model state variable (xm) is controlled depending on the output variable difference (Δy);
• and
• a throughput mode, in which the model state variable (xm) is calculated independently of the actual temperature (y).