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DE-102024133131-A1 - Stator of an electric machine and electric machine

DE102024133131A1DE 102024133131 A1DE102024133131 A1DE 102024133131A1DE-102024133131-A1

Abstract

A stator for a multiphase electric machine is provided, comprising a cylindrical laminated core with a predetermined number of axially parallel slots, each slot serving to accommodate at least one electrical conductor of a phase of the electric machine. The slots are formed in the laminated core such that at least two planes of slots, differing from each other in the radial direction, are formed, and at least two of the planes are inclined in opposite directions to each other.

Inventors

  • Thomas Hubert
  • Rujian Guo
  • Jörg Schneider

Assignees

  • DR. ING. H.C. F. PORSCHE AKTIENGESELLSCHAFT

Dates

Publication Date
20260513
Application Date
20241113

Claims (10)

  1. Stator of a multiphase electric machine, comprising a cylindrical laminated core (1) with a predetermined number of slots (10) extending parallel to each other in the axial direction (Y), wherein each slot (10) serves to accommodate at least one electrical conductor (20-22) of a phase (U, V, W) of the electric machine, characterized in that - the grooves (10) are formed in the sheet metal stack (1) such that at least two planes (E1, E2) differing from each other in the radial direction (R) are formed on the grooves (10), and - that at least two of the planes (E1, E2) are inclined in opposite directions to each other.
  2. Stator after Claim 1 , wherein the planes (E1, E2) are separated from each other by a web of the laminated core (1).
  3. Stator after Claim 1 or 2 , wherein the grooves are inclined such that an offset of the grooves (10) of one plane (E1, E2) to the grooves (10) of the other plane (E1, E2) by one or more grooves (10) results.
  4. Stator after Claim 3 , where the maximum offset of slots (10) corresponds to a coil width (w).
  5. Stator according to one of the preceding claims, wherein more than two planes (E1, E2) are provided, wherein - two or more successive planes (E1, E2) are inclined in the same way, or wherein - the planes (E1, E2) are alternately inclined in opposite directions.
  6. Stator according to one of the preceding claims, wherein several layers of conductors (20-22) are provided per level (E1, E2).
  7. Stator according to one of the preceding claims, wherein several conductors (20-22) belonging to a phase (U, V, W) of the electrical machine are arranged in adjacent slots (10).
  8. Stator according to one of the preceding claims, wherein the electrical conductors (20-22) are formed as flat wire or round wire.
  9. Stator according to one of the preceding claims, wherein the conductors (20-22) are formed as a plug-in coil or continuously wound.
  10. Electric machine, in particular permanent excitation synchronous machine, comprising a stator according to one of the preceding claims, and a rotor.

Description

The invention relates to the field of electromobility and in particular to the field of the design of electrical machines. Permanent magnet synchronous machines, hereinafter referred to as electric machines, are known from the prior art. They are, for example, powered by a high-speed converter. The stator of the electric machine contains coils which, through their spatial arrangement, the voltages applied to the coils, and the resulting current flow, generate a rotating magnetic field through superposition (due to the rotation of the rotor). The windings of the coils can be divided into concentrated and distributed windings. In a concentrated winding, only one stator tooth is wound. It has very small winding heads at the top and bottom of the motor. In contrast, in a distributed winding, at least two stator teeth are always wound. A significant advantage of the distributed winding is that the resulting back EMF (electromagnetic force) has a more uniform, usually sinusoidal, curve. This results in a very low harmonic content and reduces iron losses in the stator laminations. The coil gauge of a coil is determined by the number of poles and slots, as well as the winding design. To reduce cogging torque or general torque pulsations, e.g., caused by slotting effects, the stators or rotors of electrical machines are often designed with a skew or staggered configuration. In a skew design, the conductors in the laminated core (or the magnets on the rotor) do not run in a purely axial direction, but at an angle. The degree of skew is described by the circumferential angle of the skew. When one part of a machine is skew and the other part is unskewn, the flux relationship between the stator and rotor changes compared to an unskewn machine. The flux reduction due to continuous skew lowers the mean torque and is expressed as the skew factor, a function of the skew angle and the number of pole pairs of harmonics. Skew rotors or stators in electrical machines is a common method for reducing torque ripple and noise, at the cost of lower mean torque. One object of the invention is to provide an improved design of an electric machine that achieves the highest possible torque with the lowest possible losses. This task is solved by the features of independent claims. Advantageous embodiments are the subject of dependent claims. A stator for a multiphase electric machine is provided, comprising a cylindrical laminated core with a predetermined number of axially parallel slots, each slot serving to accommodate at least one electrical conductor of a phase of the electric machine. The slots are formed in the laminated core such that at least two planes of slots, differing from each other in the radial direction, are formed, and at least two of the planes are inclined in opposite directions to each other. In one embodiment, the levels are separated from each other by a web of the sheet metal stack. In one embodiment, the grooves are inclined in such a way that an offset of the grooves of one plane to the grooves of the other plane by one or more grooves results. In one version, the maximum offset of slots corresponds to a coil width. In one embodiment, more than two planes are provided, with each pair or more successive planes being inclined in the same way. Alternatively, the planes are alternately inclined in opposite directions. One design provides for multiple layers of ladders per level. In one embodiment, it is provided that several conductors belonging to one phase of the electrical machine are arranged in adjacent slots. In one version, the electrical conductors are designed as flat or round wires. In one embodiment, the conductors are designed as plug-in coils or continuously wound. Furthermore, an electric machine, in particular a permanent magnet synchronous machine, comprising a stator and a rotor, is provided. Further features and advantages of the invention will become apparent from the following description of exemplary embodiments of the invention, with reference to the figures in the drawing, which shows details of the invention, and from the claims. The individual features can be implemented individually or in any combination in a variant of the invention. Preferred embodiments of the invention are explained in more detail below with reference to the accompanying figures. 1 shows an oblique top view of a sheet metal stack with grooves and electrical conductors inserted therein according to the state of the art. 2 shows an oblique top view of the in 1 electrical conductor located in the sheet metal package. 3 shows a view of the in 2 The depicted electrical conductor in its unrolled state. 4 shows an oblique top view of a sheet metal stack with grooves and electrical conductors inserted therein according to an embodiment of the present invention. 5 shows an oblique top view of the in 4 electrical conductor located in the sheet metal package. 6 shows a view of the in 5 The depicted electrical conductor in its unro