PERMANENT MAGNET ROTOR AND PERMANENT MAGNET MOTOR FOR A MOTOR VEHICLE

Abstract

A permanent magnet rotor (1) for a permanent magnet motor is provided, comprising a laminated core (2), mounting pockets (3) formed in the laminated core (2), and permanent magnets (10, 20) each segmented and mounted in one of the mounting pockets (3). The permanent magnets (10, 20) include at least one asymmetrically segmented permanent magnet (10), which is segmented only at an end region facing away from an axis of rotation of the permanent magnet rotor (1).

Description

[0001] The present disclosure relates to a permanent magnet rotor, a permanent magnet motor having the permanent magnet rotor, and / or a motor vehicle having the permanent magnet motor.

[0002] Electric motors can be used in motor vehicles, for example, as traction motors. Various types of electric motors are known, including synchronous motors. These are single-phase and three-phase synchronous motors in motor mode, in which a constantly magnetized rotor (or armature) is driven synchronously by a moving rotating magnetic field in the stator during normal operation. The rotor can have permanent magnets or electromagnets for constant magnetization.

[0003] The energy provided by the magnetic interaction between the stator and the rotor can be tapped via the rotation of the rotor and used, for example, to drive the electrically powered motor vehicle or another machine in the motor vehicle.

[0004] If the rotor has permanent magnets, they are typically housed in an active part of the rotor, which is usually designed as a laminated core. The permanent magnets are often segmented to reduce eddy current losses. Segmentation is usually done in axial segmentation, meaning several magnet segments are inserted axially into the rotor laminated core.

[0005] To further reduce losses, the permanent magnets can also be tangentially segmented, whereby the segments are placed loosely in the rotor during assembly, for example, or are first glued outside the motor and then inserted into the rotor.

[0006] During the production of permanent magnets, they are usually sintered in large blocks and then cut to the desired size. However, segmentation increases the manufacturing effort and also the amount of magnet waste.

[0007] DE 10 2021 206 967 A1 describes a permanent magnet motor comprising a rotor assembly defining magnet pockets and a segmented permanent magnet disposed in each of the magnet pockets. The permanent magnet comprises a plurality of magnet segments, including one or more magnet segments comprising a different magnetic material than another or other magnet segments. The segmented permanent magnet is segmented in a circumferential direction.

[0008] WO 2022 / 121276 A1 describes a V-shaped, segmented permanent magnet synchronous electric motor rotor. A plurality of permanent magnet units are arranged on a rotor iron core of the rotor and symmetrically around the axis of the rotor iron core. Each permanent magnet unit comprises a V-shaped magnetic steel combination consisting of a magnetic steel unit and two magnetic steel segments of different widths, with the magnetic steel unit and the two magnetic steel segments arranged in a V-shape.

[0009] DE 10 2011 078 054 A1 describes a lamination pack for a rotor of an electric machine, comprising a plurality of laminations arranged one behind the other in the axial direction. A plurality of receiving spaces for accommodating permanent magnets are formed in the lamination pack.

[0010] Against the background of this prior art, the object of the present disclosure is to provide a device and / or a method which are each suitable for enriching the prior art.

[0011] The problem is solved by the features of the independent claims. The subordinate claims and the dependent claims each contain optional developments of the disclosure.

[0012] The task is then solved by a permanent magnet rotor for a permanent magnet motor.

[0013] The permanent magnet rotor comprises a laminated core and receiving pockets formed in the laminated core. The permanent magnet rotor may comprise a rotor shaft, wherein the laminated core may be formed as part of the rotor shaft or may be arranged on the rotor shaft, e.g., circumferentially surrounding the rotor shaft.

[0014] The permanent magnet rotor comprises permanent magnets, each of which is segmented and housed in one of the receiving pockets.

[0015] The permanent magnets have at least one asymmetrically segmented permanent magnet which is segmented only at one end region which is arranged facing away from a rotational axis of the permanent magnet rotor.

[0016] The permanent magnet rotor described above offers a number of advantages. For example, during the development of the present disclosure, it was determined, among other things based on simulations, that cyclone losses are concentrated particularly in the respective end region of the permanent magnets facing the motor stator or facing away from the rotational axis of the permanent magnet rotor. Segmentation only in this end region therefore reduces the effectiveness in reducing cyclone losses only slightly compared to, for example, symmetrical segmentation. At the same time, the manufacturing effort for the permanent magnet rotor or the segmented permanent magnets is reduced due to the reduced number of segmentations. In addition, this also advantageously reduces magnet waste during production.These advantages, which arise from a manufacturing time and cost perspective, outweigh the disadvantage of the slightly reduced efficiency caused by segmentation. Thus, the present disclosure provides a cost-optimized magnet segmentation for reducing losses in a permanent magnet rotor.

[0017] Possible further developments of the permanent magnet rotor described above are explained in detail below.

[0018] The permanent magnets can each have segmented sections. The permanent magnets can be segmented such that the respective segmented sections are arranged next to one another in a direction that extends (e.g., in a cross-sectional plane of the permanent magnet rotor or the laminated core) obliquely, radially, and / or tangentially to the rotational axis of the permanent magnet rotor.

[0019] The permanent magnets can be plate-shaped.

[0020] A respective width or length direction of the permanent magnets can extend (e.g. in a cross-sectional plane of the permanent magnet rotor or the laminated core) in the direction obliquely, radially and / or tangentially to the axis of rotation of the permanent magnet rotor.

[0021] A respective length, width or height direction of the permanent magnets can extend in the axial direction of the permanent magnet rotor.

[0022] The respective segment sections can be connected and / or glued together.

[0023] The at least one asymmetrically segmented permanent magnet can have a poka-yoke protection at the end area. The poka-yoke protection can serve to ensure the correct position or installation of the at least one asymmetrically segmented permanent magnet in the permanent magnet rotor.

[0024] An outermost segment section of the asymmetrically segmented permanent magnet can have a step. The poka-yoke protection can be arranged within the step to create a positive connection between the outermost segment section and the laminated core.

[0025] The Poka-Yoke safety device can be designed as a nose and / or a clamping nose.

[0026] The permanent magnets may be jammed (and / or jammed) in the receiving pockets.

[0027] In the radial direction of the permanent magnet rotor, several of the receiving pockets can be formed one behind the other.

[0028] The permanent magnets can comprise several asymmetrically segmented permanent magnets. It is also conceivable that all permanent magnets can be designed as asymmetrically segmented permanent magnets.

[0029] The permanent magnets may be arranged in a pattern that repeats in the circumferential direction and / or in the axial direction of the permanent magnet rotor.

[0030] Several of the permanent magnets can be arranged one behind the other in the axial direction of the permanent magnet rotor. Alternatively, or additionally, at least some of the permanent magnets can also be segmented, e.g., symmetrically, in the axial direction of the permanent magnet rotor.

[0031] The above description can be summarized in other words and in a possible more concrete embodiment of the disclosure as described below, whereby the following description is not to be interpreted as limiting the disclosure.

[0032] Simulations have shown that losses in permanent magnets of a rotor are concentrated in the edge region of the permanent magnets, closest to the stator. Therefore, from a cost perspective, it may be possible to implement tangential and / or radial segmentation only in this edge region, i.e., to segment permanent magnets asymmetrically.

[0033] To ensure the correct mounting of the permanent magnets (with the segmented areas positioned toward the stator), a poka-yoke protection can be provided (in each case). For example, one or more segments can be geometrically designed to accommodate poka-yoke protection without significant cost penalty, e.g., a step within a segment.

[0034] This can provide a further advantage because the step in the permanent magnet allows for an additional degree of design freedom in the highly loaded sheet metal cross-section at this location. The step allows for minimal magnetic mass loss (and thus a slight torque reduction), while creating the degree of freedom to partially thicken the highly loaded sheet metal cross-section or to increase (tangent-continuous) radii, thus reducing load hotspots.

[0035] Furthermore, a permanent magnet motor, optionally a permanent magnet synchronous motor and / or self-excited synchronous motor, is provided for a motor vehicle, which comprises the permanent magnet rotor described above.

[0036] The permanent magnet motor may comprise a stator that surrounds the permanent magnet rotor at least circumferentially or in the circumferential direction.

[0037] The stator can have several electrical coils that can be supplied with alternating current and / or three-phase current to drive the permanent magnet rotor.

[0038] The permanent magnet motor can be operated in motor mode and / or generator mode. The permanent magnet motor can also be referred to as an electric machine.

[0039] What was described above with reference to the permanent magnet rotor also applies analogously to the permanent magnet motor and vice versa.

[0040] Furthermore, a motor vehicle is provided which comprises the permanent magnet motor and / or the permanent magnet rotor described above.

[0041] The motor vehicle can be an electrically driven, e.g., drivable, motor vehicle. The permanent magnet motor can be designed as a traction motor or traction machine of the motor vehicle. The motor vehicle can include a traction battery, e.g., for supplying the stator with electrical energy or, via at least one converter, with alternating current.

[0042] The motor vehicle may be a passenger car, in particular an automobile, or a commercial vehicle, such as a truck.

[0043] What has been described above with reference to the permanent magnet motor and the permanent magnet rotor also applies analogously to the motor vehicle and vice versa.

[0044] Below are optional embodiments with reference to Fig. 1 and Fig. 2 described. Fig. 1 shows schematically a section of a permanent magnet rotor according to the disclosure, and Fig. 2 shows schematically a section of the permanent magnet rotor according to another embodiment.

[0045] Fig. Figure 1 shows only a schematic and partial view of the permanent magnet rotor 1 for a permanent magnet motor, e.g., of a motor vehicle. The permanent magnet rotor 1 comprises a laminated core 2 and receiving pockets 3 formed in the laminated core 2.

[0046] The permanent magnet rotor 1 further comprises permanent magnets 10, 20, which are each accommodated in a segmented manner in one of the receiving pockets 3, e.g. clamped.

[0047] The receiving pockets 3 can be designed in such a way or the permanent magnets 10, 20 can be arranged in such a way that in the radial direction of the permanent magnet rotor 1 a plurality of the receiving pockets 3 are formed one behind the other.

[0048] The permanent magnet rotor 1 has at least one asymmetrically segmented permanent magnet 10, which is segmented only at an end region facing away from a rotational axis of the permanent magnet rotor 1. The permanent magnet rotor 1 can accordingly have one or more symmetrically segmented permanent magnets 20.

[0049] It is conceivable that several or even all permanent magnets of the permanent magnet rotor 1 are asymmetrically segmented.

[0050] The permanent magnets 10, 20 each have a plurality of segment sections 11, 12, 21, wherein the permanent magnets 10, 20 are segmented such that the respective segment sections 11, 12, 21 are arranged next to one another in a direction which, for example in a cross-sectional plane of the permanent magnet rotor 1, is oblique, radial and / or tangential to the axis of rotation of the permanent magnet rotor 1.

[0051] The permanent magnets 10, 20 can be plate-shaped. Furthermore, the permanent magnets 10, 20 can be arranged such that a respective width or length direction of the permanent magnets 10, 20 extends obliquely, radially, and / or tangentially to the rotational axis of the permanent magnet rotor 1, and a respective length, width, or height direction of the permanent magnets 10, 20 extends in the axial direction of the permanent magnet rotor 1.

[0052] Furthermore, the respective segment sections 11, 12, 21 can be connected to one another, e.g., glued, to form the permanent magnets 10, 20.

[0053] The Fig. The arrangement of the permanent magnets 10, 20 shown in Figure 1 may correspond to an arrangement pattern that repeats in the circumferential direction of the permanent magnet rotor 1. Furthermore, this arrangement may also repeat in the axial direction of the permanent magnet rotor 1, e.g., at equal intervals.

[0054] As in Fig. 2 is shown schematically, the at least one asymmetrically segmented permanent magnet 10 in one embodiment has a poka-yoke protection 30 at the end region.

[0055] For this purpose, an outermost segment section 12 of the asymmetrically segmented permanent magnet 10 has a step, with the poka-yoke securing device 30 arranged within the step to create a positive connection between the outermost segment section 12 and the permanent magnet rotor 1. The poka-yoke securing device 30 can be designed, for example, as a lug and / or a clamping lug. The poka-yoke securing device 30 can be designed on the laminated core 2 and / or as part of the laminated core 2.

[0056] The poka-yoke protection 30 serves to ensure the correct mounting of the asymmetrically segmented permanent magnet 10, with the segmented end region correctly positioned away from the rotational axis of the permanent magnet rotor 1. The outermost segment section 12 can be geometrically designed without any significant cost disadvantage, for example, by forming the step.

[0057] The poka-yoke protection 30 and the formed step also result in the advantage of an additional degree of design freedom in the region of a highly loaded cross-section 40 of the laminated core 2. For example, this cross-section 40 can at least partially have a greater thickness or the receiving pocket 3 can have a different, e.g., a larger, radius in this region in order to thereby, for example, reduce the load. List of reference symbols 1 permanent magnet rotor 2 sheet packages 3 pockets 10 asymmetrically segmented permanent magnet 20 (symmetrically segmented) permanent magnets 11, 12, 21 segment sections 30 Poka-Yoke protection 40 Highly stressed cross-section of the laminated core QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 206 967 A1

[0007] WO 2022 / 121276 A1

[0008] DE 10 2011 078 054 A1

[0009]

Claims

[1] Permanent magnet rotor (1) for a permanent magnet motor, comprising: - a laminated core (2); - receiving pockets (3) formed in the laminated core (2); and - permanent magnets (10, 20), each of which is accommodated in a segmented manner in one of the receiving pockets (3), characterized by , that - the permanent magnets (10, 20) have at least one asymmetrically segmented permanent magnet (10) which is segmented only at an end region which is arranged facing away from a rotational axis of the permanent magnet rotor (1). [2] Permanent magnet rotor (1) according to claim 1, characterized by that the permanent magnets (10, 20) each have segment sections (11, 12, 21) and are segmented such that the respective segment sections (11, 12, 21) are arranged next to one another in a direction which extends obliquely, radially and / or tangentially to the axis of rotation of the permanent magnet rotor (1). [3] Permanent magnet rotor (1) according to claim 2, characterized by , that - the permanent magnets (10, 20) are plate-shaped, - a respective width or length direction of the permanent magnets (10, 20) extends in the direction obliquely, radially and / or tangentially to the axis of rotation of the permanent magnet rotor (1), - a respective length, width or height direction of the permanent magnets (10, 20) extends in the axial direction of the permanent magnet rotor (1), and - the respective segment sections (11, 12, 21) are connected and / or glued to one another. [4] Permanent magnet rotor (1) according to one of the preceding claims, characterized by that the at least one asymmetrically segmented permanent magnet (10) has a poka-yoke protection (30) at the end region. [5] Permanent magnet rotor (1) according to claim 4, characterized by , that - an outermost segment section (12) of the asymmetrically segmented permanent magnet (10) has a step, and - the poka-yoke securing device (30) is arranged within the step to produce a positive connection between the outermost segment section (12) and the laminated core (2). [6] Permanent magnet rotor (1) according to one of the preceding claims, characterized by that the Poka-Yoke safety device (30) is designed as a nose and / or clamping nose. [7] Permanent magnet rotor (1) according to one of the preceding claims, characterized by that the permanent magnets (10, 20) are clamped in the receiving pockets (3). [8] Permanent magnet rotor (1) according to one of the preceding claims, characterized by that in the radial direction of the permanent magnet rotor (1) several of the receiving pockets (3) are formed one behind the other. [9] Permanent magnet motor for a motor vehicle, characterized bythat the permanent magnet motor comprises the permanent magnet rotor (1) according to one of the preceding claims. [10] Motor vehicle, characterized by that the motor vehicle comprises the permanent magnet motor according to claim 9.

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