Abstract: The invention relates to the field of electric drive devices and electric machines, such as electric drive motors and electric generators for industrial applications, and more particularly to a method and an arrangement for identification of lateral vibration characteristics of an electric machine. The arrangement for identification of lateral vibration characteristics of an electric machine according to the present invention includes a frequency converter, one or more vibration sensors and an electric machine, wherein said frequency converter is arranged for producing torsional excitation, said torsional excitation effecting lateral vibration in said electric machine; and wherein said one or more vibration sensors include at least one lateral vibration sensor arranged for measuring the lateral vibration from said electric machine as excitation response and for producing lateral vibration data.

Abstract: An annular stator provided with axial stator slots and stator teeth formed between adjacent stator slots. Each stator slot receives a conductor of a stator winding. The stator is formed of stator sectors. Each stator sector includes two outermost stator teeth and intermediate stator teeth between the two outermost stator teeth. A width of the two outermost stator teeth is equal. Adjacent stator slots within each stator sector are distanced by a first slot pitch and adjacent stator slots belonging to different stator sectors are distanced by a second slot pitch. The first slot pitch is smaller than the second slot pitch.

Abstract: The disclosure relates to an electric induction machine in which a chamfer region is provided between each respective rotor groove and rotor bar at a position corresponding to a radially outer internal corner region of the rotor groove. Suitably, the chamfer region has a relative magnetic permeability less than that of the rotor frame, and an electrical resistivity higher than that of the rotor bar. Moreover, a minimum diameter of the chamfer region is suitably larger than a manufacturing-tolerances derived maximum clearance between the respective rotor groove and robot bar, if any.

Abstract: A method for controlling a synchronous double stator electric machine. A first stator and a first set of magnetic poles on a common rotor forms a first electric machine. A second stator and a second set of magnetic poles on the rotor forms a second electric machine. The first electric machine and the second electric machine is shifted mechanically by a predetermined angle. An electrical shift is produced to the control of at least the mechanically shifted electric machine with a respective frequency converter in order to at least partly compensate for the mechanical shift in the mechanically shifted electric machine.

Abstract: A field of electric drive devices and electric machines, such as electric motors and electric generators for industrial applications, and more particularly to a method, an arrangement and a frequency converter for controlling lateral vibration of an electric machine. The arrangement of the present invention for controlling lateral vibration of an electric machine includes a frequency converter, one or more vibration sensors and an electric machine, wherein the one or more vibration sensors is/are arranged for measuring the lateral vibration from the electric machine and for producing measured vibration data; and wherein the frequency converter is arranged for generating a control torque for exerting the control torque on the stator of the electric machine, the control torque being determined utilizing the measured vibration data.

Abstract: The thermal conductivity of the electrical paper insulation could be increased if the paper material is either enriched or fully substituted by a material with higher thermal conductivity. Diamond as enrichment material will be the right choice because besides the high thermal conductivity, it also acts as an excellent electrical insulator and has good mechanical properties. The thermal conductivity of the diamond is kdiamond=2200 [W/mK], that is even more than 7000 times higher than the paper material. Diamond enriched insulation papers have not existed before this invention. In the proposed structure the diamond particles are held in place also by the fibrous substance of the paper itself, without the need of a holding matrix material by default, as shown in FIG. 1. The diamond particles mixed in the paper can also penetrate the paper across creating a thermal bridge between the insulated parts while maintaining strong electrical insulation.

Abstract: A method for controlling a synchronous double stator electric machine. A first stator and a first set of magnetic poles on a common rotor forms a first electric machine. A second stator and a second set of magnetic poles on the rotor forms a second electric machine. The first electric machine and the second electric machine is shifted mechanically by a predetermined angle. An electrical shift is produced to the control of at least the mechanically shifted electric machine with a respective frequency converter in order to at least partly compensate for the mechanical shift in the mechanically shifted electric machine.

Abstract: An electric machine includes a support frame, an outer rotor, a stator, and a dampening mechanism. The outer rotor and the stator are supported to the support frame, and the dampening mechanism is configured for dampening vibrations of the outer rotor. The outer rotor includes an annular end plate, and the dampening mechanism includes a first damper having a first constraint element and a first visco-elastic layer provided on a surface of the first constraint element. The first constraint element is connected to the annular end plate through the first visco-elastic layer.

Abstract: The disclosure relates to an electric machine with a permanent magnet rotor, where permanent magnets have been fitted on an outer surface of a cylindrical rotor, and relates to a permanent magnet. The permanent magnets forming the electric machine's rotor pole are shaped so that the electric machine's air gap is substantially constant in a middle of the pole, and the air gap increases in an essentially straightforward manner when moving towards the edge of the pole. The permanent magnet is of an even thickness in the middle, and becomes thinner towards the edges. This can result in a decrease in the torque ripple and cogging torque of an electric machine.

Abstract: The disclosure relates to an electric machine with a permanent magnet rotor, where permanent magnets have been fitted on an outer surface of a cylindrical rotor, and relates to a permanent magnet. The permanent magnets forming the electric machine's rotor pole are shaped so that the electric machine's air gap is substantially constant in a middle of the pole, and the air gap increases in an essentially straightforward manner when moving towards the edge of the pole. The permanent magnet is of an even thickness in the middle, and becomes thinner towards the edges. This can result in a decrease in the torque ripple and cogging torque of an electric machine.