Abstract: A method for starting an electric motor having a rotor, comprising the following steps:—driving the rotor with a first torque in a first rotational direction, wherein a maximum value of the first torque is not higher than a maximum countertorque acting counter to the rotation of the rotor, so that the rotor comes to a standstill in a first stationary position;—driving the rotor starting from the first stationary position in a second rotational direction that is counter to the first rotational direction until the rotor comes to a standstill in a predefined second stationary position; and—starting from the rotor in the first rotational direction starting from the second stationary position.

Abstract: A method for monitoring a controller for controlling and/or monitoring a three-phase electric motor, in particular an asynchronous or synchronous motor, wherein two phase currents are measured and an error signal is generated if at least one of the two measured phase currents is essentially zero. An error signal is also generated if none of the two measured phase currents is essentially zero, but a sum formed of the two measured phase currents is essentially zero.

Abstract: A method for starting an electric motor having a rotor, comprising the following steps: —driving the rotor with a first torque in a first rotational direction, wherein a maximum value of the first torque is not higher than a maximum countertorque acting counter to the rotation of the rotor, so that the rotor comes to a standstill in a first stationary position; —driving the rotor starting from the first stationary position in a second rotational direction that is counter to the first rotational direction until the rotor comes to a standstill in a predefined second stationary position; and —starting from the rotor in the first rotational direction starting from the second stationary position.

Abstract: A method for monitoring a controller for controlling and/or monitoring a three-phase electric motor, in particular an asynchronous or synchronous motor, wherein two phase currents are measured and an error signal is generated if at least one of the two measured phase currents is essentially zero. An error signal is also generated if none of the two measured phase currents is essentially zero, but a sum formed of the two measured phase currents is essentially zero.

Abstract: An electric machine, especially a brushless DC motor. Said electric machine comprises a rotor and a stator which is provided with current-carrying coils. Said rotor, in the circumferential direction, is provided with a plurality of permanent magnets that are embedded in respective magnet retainers between the peripheral surface and the shaft of the rotor in such a manner that the permanent magnets, in the radial direction, are completely encircled by the peripheral surface of the rotor. In the area of the magnet retainer, recesses extend laterally in the circumferential direction of the rotor and axially within the rotor.

Abstract: An electric machine, especially a brushless DC motor. Said electric machine comprises a rotor and a stator which is provided with current-carrying coils. Said rotor, in the circumferential direction, is provided with a plurality of permanent magnets that are embedded in respective magnet retainers between the peripheral surface and the shaft of the rotor in such a manner that the permanent magnets, in the radial direction, are completely encircled by the peripheral surface of the rotor. In the area of the magnet retainer, recesses extend laterally in the circumferential direction of the rotor and axially within the rotor.

Abstract: A laminate core of a stator of an electrical machine with an internal rotor includes slots each having a slit opening dimensioned such that only a single winding wire can be inserted therethrough into the slot.