Abstract: A switching arrangement with a B6 bridge for controlling an electric motor is provided. The lower semiconductor switches of each half bridge of the B6 bridge are connected to a motor ground via a common summing shunt. The switching arrangement includes a monitoring device for monitoring a current through the summing shunt based on a voltage that is dropped across the summing shunt. The monitoring device detects, in the event of a reverse current through the summing shunt that is higher than a predefined threshold value and lasts longer than a predefined period, a ground connection on the phase for which the semiconductor switches of the half bridge connected to this phase were last switched over such that the respective upper semiconductor switch is open and the respective lower semiconductor switch is closed. A method for detecting a ground connection of a phase of the electric motor is also provided.

Abstract: The invention relates to a method for operating a rotating electric machine (1) having a rotor (3), a polyphase excitation winding (5) and a commutation apparatus (9) for commutating excitation winding currents of the excitation winding (5) depending on rotor position values (R) for rotor positions of the rotor (3). First measurement values (A) for the rotor positions are detected by means of a first sensor apparatus (13) and second measurement values (B) for the rotor positions are detected by means of a second sensor apparatus (15). For the commutation of the excitation winding currents, the rotor position values (R) are formed from weighted mean values (M) of the first measurement values (A) and the second measurement values (B).

Abstract: In a method for controlling an operation of an electric motor, electric voltages applied to electric phases of the electric motor are generated and output in a modulation in a controlled manner dependent on a rotor position of the electric motor and a target/actual comparison of at least one first variable which characterizes a load on the electric motor or an actual rotational speed of the electric motor. A rotor position angle, which characterizes the rotor position, is complemented with a specified preliminary control angle and another regulated preliminary control angle component upon reaching a field weakening range of the electric motor so as to form a sum angle. The sum angle is used to characterize the rotor position in the modulation upon reaching the field weakening range. The disclosure also relates to a device for controlling an operation of an electric motor.

Abstract: The invention relates to a method for operating a rotating electric machine (1) having a rotor (3), a polyphase excitation winding (5) and a commutation apparatus (9) for commutating excitation winding currents of the excitation winding (5) depending on rotor position values (R) for rotor positions of the rotor (3). First measurement values (A) for the rotor positions are detected by means of a first sensor apparatus (13) and second measurement values (B) for the rotor positions are detected by means of a second sensor apparatus (15). For the commutation of the excitation winding currents, the rotor position values (R) are formed from weighted mean values (M) of the first measurement values (A) and the second measurement values (B).

Abstract: In a method for controlling an operation of an electric motor, electric voltages applied to electric phases of the electric motor are generated and output in a modulation in a controlled manner dependent on a rotor position of the electric motor and a target/actual comparison of at least one first variable which characterizes a load on the electric motor or an actual rotational speed of the electric motor. A rotor position angle, which characterizes the rotor position, is complemented with a specified preliminary control angle and another regulated preliminary control angle component upon reaching a field weakening range of the electric motor so as to form a sum angle. The sum angle is used to characterize the rotor position in the modulation upon reaching the field weakening range. The disclosure also relates to a device for controlling an operation of an electric motor.

Abstract: A method recognizes a wire-break fault during operation of a brushless DC motor. A switch-on delay duration of a transition of an electrical phase potential that rests on the stator winding phase from a switch-off potential to a switch-on potential and a switch-off delay duration of the transition of the phase potential from the switch-on potential to the switch-off potential are detected for a stator winding phase of the stator winding of the motor during each pulse width modulation cycle period. Moreover, a lower deviation limit is defined for a deviation of detected switch-off delay durations from detected switch-on delay durations. A wire-break fault is deduced if the deviations of the detected switch-off delay durations from the detected switch-on delay durations fall below the lower deviation limit.

Abstract: A method recognizes a wire-break fault during operation of a brushless DC motor. A switch-on delay duration of a transition of an electrical phase potential that rests on the stator winding phase from a switch-off potential to a switch-on potential and a switch-off delay duration of the transition of the phase potential from the switch-on potential to the switch-off potential are detected for a stator winding phase of the stator winding of the motor during each pulse width modulation cycle period. Moreover, a lower deviation limit is defined for a deviation of detected switch-off delay durations from detected switch-on delay durations. A wire-break fault is deduced if the deviations of the detected switch-off delay durations from the detected switch-on delay durations fall below the lower deviation limit.