Abstract: A method for switching off a current-excited synchronous machine of a motor vehicle, the current-excited synchronous machine having a rotor supplied by an excitation circuit of power electronics and a stator supplied via a bridge circuit of the power electronics, the method including interrupting a current supply to the rotor and the stator. The method further includes switching over the excitation circuit of the power electronics to a first freewheeling position, whereby energy contained in the excitation circuit and in the rotor is fed into a first energy store via a first feedback arrangement, and switching over the bridge circuit of the power electronics to a second freewheeling position, whereby energy contained in the bridge circuit and in the stator is fed into a second energy store via a second feedback arrangement.

Abstract: A pole shoe of an electric machine limits a winding surface of a rotor that can rotate about an axis of rotation. The pole shoe is connected to a pole web of the rotor. An outer side of the pole shoe, which faces away from the pole web in the connected state, has a first region having a substantially sinusoidal contour profile and a second region having a second contour profile. The second contour profile is different from the first contour profile and is formed in such a way that the winding surface in a circumferential direction of the rotor is lengthened with respect to a winding surface of a pole shoe having an outer side extending exclusively substantially sinusoidally.

Abstract: An electrical synchronous machine is provided for a rail-free vehicle. The vehicle has drive wheels and the synchronous machine is designed to generate a torque, which propels the vehicle, at the drive wheels. The synchronous machine has a stator and a rotor which rotates around the stator, wherein the stator has a stator winding of at least three-phase construction for forming a rotating stator magnetic field, and wherein the rotor has at least one rotor winding which is designed for forming a rotor magnetic field. A method for at least partially circumferentially establishing a current-excited synchronous machine provides a rotor yoke, provides a large number of rotor poles, fastens the rotor poles to the rotor yoke for forming a rotor, provides a stator, and inserts the stator into the rotor.

Abstract: A rotor for an electrical machine has a rotor core with a center line, which forms an axis of rotation. The rotor core can be subdivided by a plurality of imaginary radial planes, which extend radially from the axis of rotation at regular angular intervals. For each radial plane, at least one pair of winding grooves is formed, which extend through the rotor core to either side of the radial plane with the radial plane serving as the plane of symmetry. A winding is arranged in each pair of winding grooves, in winding receiving areas of the winding grooves, which winding extends through the two winding grooves of the pair. Each winding groove is bounded in its winding receiving area on its side facing the assigned radial plane by a side face, which continues in a manner free from projections, in the sense of projections in a direction away from the radial plane, from the winding receiving area to the radially outer end of the winding groove.

Abstract: An electrical machine has a rotor with a hollow shaft which in its interior delimits a hollow shaft axial channel that extends in the axial direction and into which a cooling fluid can flow during operation of the electrical machine. A laminated rotor core is fitted radially to the outside of the hollow shaft and has two axial end sides. An axial channel which is delimited by the laminated rotor core extends in the axial direction from one of the two end sides of the laminated rotor core to the other of the two end sides of the laminated rotor core and is connected in a fluid-conducting manner to the hollow shaft axial channel, so that, during operation of the electrical machine, the cooling fluid can flow from the hollow shaft axial channel to the end sides via the axial channel and can flow radially to the outside downstream of the axial channel owing to centrifugal force.

Abstract: A pole shoe of an electric machine limits a winding surface of a rotor that can rotate about an axis of rotation. The pole shoe is connected to a pole web of the rotor. An outer side of the pole shoe, which faces away from the pole web in the connected state, has a first region having a substantially sinusoidal contour profile and a second region having a second contour profile. The second contour profile is different from the first contour profile and is formed in such a way that the winding surface in a circumferential direction of the rotor is lengthened with respect to a winding surface of a pole shoe having an outer side extending exclusively substantially sinusoidally.

Abstract: A method for switching off a current-excited synchronous machine of a motor vehicle, the current-excited synchronous machine having a rotor supplied by an excitation circuit of power electronics and a stator supplied via a bridge circuit of the power electronics, the method including interrupting a current supply to the rotor and the stator. The method further includes switching over the excitation circuit of the power electronics to a first freewheeling position, whereby energy contained in the excitation circuit and in the rotor is fed into a first energy store via a first feedback arrangement, and switching over the bridge circuit of the power electronics to a second freewheeling position, whereby energy contained in the bridge circuit and in the stator is fed into a second energy store via a second feedback arrangement.

Abstract: A rotor for an electrical machine has a rotor core with a center line, which forms an axis of rotation. The rotor core can be subdivided by a plurality of imaginary radial planes, which extend radially from the axis of rotation at regular angular intervals. For each radial plane, at least one pair of winding grooves is formed, which extend through the rotor core to either side of the radial plane with the radial plane serving as the plane of symmetry. A winding is arranged in each pair of winding grooves, in winding receiving areas of the winding grooves, which winding extends through the two winding grooves of the pair. Each winding groove is bounded in its winding receiving area on its side facing the assigned radial plane by a side face, which continues in a manner free from projections, in the sense of projections in a direction away from the radial plane, from the winding receiving area to the radially outer end of the winding groove.

Abstract: An electrical synchronous machine is provided for a rail-free vehicle. The vehicle has drive wheels and the synchronous machine is designed to generate a torque, which propels the vehicle, at the drive wheels. The synchronous machine has a stator and a rotor which rotates around the stator, wherein the stator has a stator winding of at least three-phase construction for forming a rotating stator magnetic field, and wherein the rotor has at least one rotor winding which is designed for forming a rotor magnetic field. A method for at least partially circumferentially establishing a current-excited synchronous machine provides a rotor yoke, provides a large number of rotor poles, fastens the rotor poles to the rotor yoke for forming a rotor, provides a stator, and inserts the stator into the rotor.

Abstract: An electrical machine has a rotor with a hollow shaft which in its interior delimits a hollow shaft axial channel that extends in the axial direction and into which a cooling fluid can flow during operation of the electrical machine. A laminated rotor core is fitted radially to the outside of the hollow shaft and has two axial end sides. An axial channel which is delimited by the laminated rotor core extends in the axial direction from one of the two end sides of the laminated rotor core to the other of the two end sides of the laminated rotor core and is connected in a fluid-conducting manner to the hollow shaft axial channel, so that, during operation of the electrical machine, the cooling fluid can flow from the hollow shaft axial channel to the end sides via the axial channel and can flow radially to the outside downstream of the axial channel owing to centrifugal force.

Abstract: A method produces a stator provided for a synchronous or asynchronous machine having a two-layer winding.