Rotor of electric machine designed as permanent magnet synchronous machine, electric machine and motor vehicle

Abstract

The invention relates to a rotor (10) of an electric machine (11) designed as a permanent magnet synchronous machine, said rotor (10) comprising a rotor base body (16) having pocket-like recesses (17, 18) which are open radially to the outside and permanent magnets (19, 20) which are positioned in the recesses (17, 18), said rotor (10) comprising poles (12) which are arranged alternately adjacent to one another and form pole pairs when viewed in the circumferential direction, wherein at least one permanent magnet group comprises permanent magnets (19, 20) arranged in recesses (17, 18) positioned in a V-shape in the region of each pole (12), which permanent magnets diverge radially outward, and wherein the radially outer ends of the permanent magnets (19, 20) arranged in the recesses (17, 18) positioned in the V-shape have outer surfaces (23, 24) with chamfers (25, 26), the rotor base body (16) has a chamfer (27) which extends in a tangential direction to or parallel to the outer circumference of the rotor base body (16) at a respective circumferential position of a respective radially outer end of a respective permanent magnet (19, 20) which extends adjacent to the outer circumference of the rotor base body (16), and wherein the rotor base body (16) supports a hoop (27) on the outer circumference.

Description

TECHNICAL FIELD

[0001] The present invention relates to a rotor of an electric machine designed as a permanent magnet synchronous electric machine. Furthermore, the present invention relates to an electric machine and to a motor vehicle. BACKGROUND

[0002] The basic design of an electric machine is known from practice. Thus, an electric machine has a housing and a stator. The stator is also called a stator. Furthermore, the electric machine has a rotor. The rotor is also called a runner. The rotor is rotatably mounted in the housing. EP 1 990 895 A2 discloses an electric machine comprising a rotor and a stator. The rotor comprises a rotor base body having pocket-like recesses in which permanent magnets are positioned. Pocket-like recesses closed radially outwardly and pocket-like recesses open radially outwardly are disclosed. In the region of each pole of the rotor, a group of permanent magnets is formed by permanent magnets arranged in the recesses.

[0003] DE 10 2018 219 244 A1 discloses a further rotor of an electric machine. The rotor base body of the rotor has recesses closed radially outwardly in which permanent magnets are arranged.

[0004] DE 199 41 107 A1 discloses a further rotor of an electric machine. The rotor has recesses arranged in a V-shape relative to each other, which are closed radially outwardly and serve for receiving permanent magnets.

[0005] US 6 891 297 B2 discloses a further rotor of an electric machine having recesses for receiving permanent magnets arranged in a V-shape relative to each other.

[0006] US 10 784 732 B2, DE 10 2022 111 494 A1, DE 10 2022 203 126 A1 and US 2023 / 0 179 045 A1 disclose a further prior art.

[0007] In motor vehicles, especially in high-performance vehicles such as sports cars or racing cars, the electric machines used as power devices require an increased amount of power, an increased amount of torque and an increased maximum speed. So far, it has been difficult to provide a rotor of a permanent magnet synchronous electric machine which can provide a high maximum speed, thereby providing a high maximum circumferential or surface speed in the order of magnitude of more than 150 m / s, especially at high power and high torque. There is a need for a rotor of an electric machine designed as a permanent magnet synchronous electric machine with which an increased power and an increased torque can be provided at a high maximum speed, thereby providing a high maximum circumferential or surface speed. SUMMARY

[0008] The task of the present invention is to create a rotor of an electric machine designed as a permanent-magnet synchronous electric machine, which has a high torque density and a high speed stability and which also requires a small installation space. Furthermore, an electric machine having such a rotor and a motor vehicle having an electric machine comprising such a rotor are to be provided. The task is solved by a rotor according to patent claim 1, an electric machine according to patent claim 12 and a motor vehicle according to patent claim 13.

[0009] The rotor according to the invention comprises a rotor base body having radially outwardly open pocket-like recesses and permanent magnets positioned in the recesses, wherein the rotor has poles which are arranged next to one another alternately and form pole pairs when viewed in the circumferential direction, wherein in the region of each pole there is respectively configured at least one permanent magnet group formed by permanent magnets arranged in V-shaped positioned recesses, which permanent magnets diverge radially outwardly.

[0010] In the rotor according to the invention, the radially outer end of the permanent magnets arranged in the V-shaped positioned recesses has an outer surface with a chamfer, which extends in the tangential direction of the outer circumference of the rotor base body or parallel thereto at the respective circumferential position of the respective radially outer end of the respective permanent magnet, which radially outer end extends adjacent to the outer circumference of the rotor base body. The rotor base body of the rotor according to the invention supports the chock / hoop on the outer circumference.

[0011] Because the permanent magnets positioned in the radially outwardly open V-shaped positioned recesses have an outer surface with a chamfer adjacent to the outer circumference of the rotor base body, which chamfer extends in the tangential direction of the outer circumference of the rotor base body or parallel thereto at the respective circumferential position of the respective radially outer end of the respective permanent magnet, the magnetic mass per pole can be increased, thus increasing the power and the torque of the electric machine. In combination with the chock on the outer circumference of the rotor base body, the maximum speed can also be increased, thus increasing the maximum circumferential speed or surface speed.

[0012] Preferably, the radially inner end of the permanent magnets arranged in the V-shaped positioned recesses has an outer surface with a chamfer, which extends in the direction of the d-axis of the respective pole or parallel to the d-axis of the respective pole, which radially inner end extends adjacent to the d-axis of the respective pole of the rotor. Again, the magnetic mass per pole can be increased and the power and the torque obtainable from the electric machine can be increased. Furthermore, the angle between the recesses positioned in a V-shape can be increased, thus the angle between the permanent magnets positioned in the recesses can be increased, which can also increase the power of the electric machine. A further advantage is the reduction of the mass to be supported, thus the requirements on the chock are reduced.

[0013] If the rotor has permanent magnets which are not uniform in their material properties, the chamfer of the permanent magnets can be used to rule out incorrect configuration of the permanent magnets during manufacture. Thus, the chamfer of the permanent magnets can also be used as a mistake-proofing feature in the manufacture of the rotor of an electric machine designed as a permanent-magnet synchronous electric machine. Attached Figure Description

[0014] Preferred further developments of the invention will derive from the dependent claims and the following description. Design examples of the invention will be explained in more detail with reference to the accompanying drawings, but the invention is not limited thereto. The drawings show:

[0015] Figure 1 A schematic cross-sectional view of a first motor designed as a permanent magnet synchronous motor, which is used as a power unit in a motor vehicle.

[0016] Figure 2 A schematic cross-sectional view of a second motor designed as a permanent magnet synchronous motor, which is used as a power unit in a motor vehicle;

[0017] Figure 3 Motor vehicles that have an electric motor used as a power source. Detailed Implementation

[0018] Figure 1 A cross-section of the rotor 10 of a motor 11 designed as a permanent magnet synchronous motor is shown. The motor 11 is preferably designed as a power unit for a motor vehicle 100, i.e., a power unit for a passenger vehicle designed as a hybrid vehicle or an electric vehicle.

[0019] The stator 13 of the motor 11 is radially outwardly adjacent to the rotor 10. The rotor 10 and the stator 13 are housed in a housing (not shown) of the motor 11, and the rotor 10 is rotatably mounted in the housing of the motor 11.

[0020] Figure 1 The diagram shows a cross-section of the rotor 10 of the motor 11 in the region of the poles 12 of the rotor 10, wherein, viewed in the circumferential direction, a plurality of poles 12 are arranged adjacent to each other and form pole pairs. Every two poles form a pole pair. The circumferential extension τp of the pole 12 is 360° / 2p. p corresponds to the number of pole pairs of the rotor 10.

[0021] The stator 13 has a groove 14 in which the stator winding 15 is arranged. The stator winding 15 preferably has three chamfers.

[0022] The rotor 10 of the motor 11 has a rotor base 16, which has bag-shaped recesses 17 and 18 and permanent magnets 19 and 20 positioned in the bag-shaped recesses 17 and 18. Figure 1 In the exemplary embodiment shown, there is a radially inner recess 17 and a radially outer recess 18, which are radially outwardly open and aligned with each other in a V-shape to accommodate permanent magnets 19 and 20.

[0023] In the region of each pole 12 of the rotor 10, thus of the electric machine 11, at least one permanent magnet group is constructed which is formed by permanent magnets 19, 20 arranged in V-shaped positioned recesses 17, 18, which permanent magnets diverge radially outward. In this way, in the exemplary embodiment shown, the permanent magnets 19 arranged in the recesses 17 form a first permanent magnet group radially inside the respective pole 12, while the permanent magnets 20 arranged in the radially outer recesses 18 form a second permanent magnet group radially outside this respective pole.

[0024] As mentioned above, Figure 1 A sectional view of a pole 12 of the rotor 10 of the electric machine 11 is shown. Figure 1 On the one hand, a d-axis 21 of the pole 12 is shown, while on the other hand, a q-axis 22 of the pole is shown.

[0025] The d-axis 21 of the respective pole 12 of the rotor 10 of the electric machine 11 extends in the radial direction in the circumferential center of the respective pole.

[0026] The q-axis 22 of the pole 12 of the rotor 10 of the electric machine 11 also extends in the radial direction at the lateral circumferential limits of the respective pole 12.

[0027] As mentioned above, the permanent magnets 19, 20 are arranged in V-shaped positioned radially outwardly open pocket-like recesses 17, 18. The radially outer end portions of the permanent magnets 19, 20 arranged in the recesses 17, 18 have outer surfaces 23, 24 with a chamfer 25, 26 which extends in the tangential direction of the outer circumference of the rotor base body 16 or parallel to this tangential direction at the respective circumferential position of the respective radially outer end portion of the respective permanent magnet 19, 20, which radially outer end portion extends adjacent to the outer circumference of the rotor base body 16.

[0028] In the exemplary embodiment shown, the respective chamfer 25, 26 at the radially outer end portion of the respective permanent magnet 19, 20 extends parallel to the tangential direction of the outer circumference of the rotor base body and is offset radially inwardly with respect to this tangential direction, so that the respective chamfer 25, 26 extends at a distance a ag from the outer circumference of the rotor base body, which distance is in particular between 0.1 mm and 6 mm, preferably between 0.2 mm and 5 mm, particularly preferably between 0.5 mm and 3.5 mm.

[0029] In contrast, the chamfer 25, 26 at the radially outer end portion of the respective permanent magnet 19, 20 can also extend tangentially to the outer circumference of the rotor at the respective circumferential position, wherein the distance a ag is 0 mm.

[0030] The rotor base body 16 supports a clamping piece 27 on the outer circumference.

[0031] Due to the design of the permanent magnets 19, 20 according to the application, the magnetic mass of each pole 12 can be increased at its radially outer end adjacent to the outer circumference of the rotor base body 16, i.e. by the chamfer 25, 26 extending tangentially or parallel to the tangential direction at the radially outer end of the respective permanent magnet 19, 20, whereby the performance can be increased in the end and thus the torque.

[0032] According to Figure 1 , the rotor base body 16 preferably overlaps with the chamfer 25, 26 of the respective permanent magnet 19, 20 at its radially outer end in the circumferential direction, thereby holding the respective permanent magnet 19, 20 in place. The clamping element 27 also holds the rotor 10 together, thereby enabling a high maximum speed for the rotor 10, thus a high maximum circumferential speed or surface speed for the rotor, while increasing the magnetic mass and thus the power and the torque.

[0033] Preferably, the radially inner end of the permanent magnet 19, 20 arranged in the V-shaped positioned recess 17, 18 has an outer surface 28, 29 with a chamfer 30, 31 extending in the direction of the d-axis 21 of the respective pole 12 or parallel to the d-axis 21 of the respective pole, the radially inner end extending adjacent to the d-axis 21 of the respective pole 12. Then, when the chamfer 30, 31 extends in the direction of the d-axis 21, the chamfer 30 of the permanent magnet 19 and the chamfer 31 of the permanent magnet 20 abut, then Figure 1 the distance d center is 0 mm. In Figure 1 , the chamfer 30 of the permanent magnet 19 and the chamfer 31 of the permanent magnet 20 do not abut each other, but are spaced apart from each other in the region of the d-axis 21 by a web 32 or 33, wherein the circumferential thickness of the respective web 32, 33 determines the distance d center between the chamfer 30 of the permanent magnet 19 and the chamfer 31 of the permanent magnet 20. This distance d center is at most 10 mm, preferably at most 5 mm, particularly preferably at most 3 mm.

[0034] By the chamfer 30, 31 at the radially inner end of the permanent magnet 19, 20, the magnetic mass of each pole 12 can also be increased in order to provide a higher power and a higher torque. Furthermore, the chamfer 30, 31 at the radially inner end of the permanent magnet 19, 20 allows a larger angle a between the radially outward diverging permanent magnets 19, 20 or between the V-shaped positioned recesses 17, 18. This is also advantageous for increasing the power and thus for increasing the torque.

[0035] In Figure 1In the exemplary embodiment shown, each pole 12 has two V-shaped recesses 17 and 18, namely, one is a radially inward recess 17, and the other is a radially outward recess 18. Permanent magnets 19 and 20 are arranged in these two recesses, forming a permanent magnet group, that is, permanent magnet 19 forms an inner permanent magnet group, and permanent magnet 20 forms an outer permanent magnet group. Compared with the exemplary embodiment shown, only one permanent magnet group can also be formed in the region of each pole 12, that is, only two recesses positioned in a V-shape relative to each other exist.

[0036] Then, if each of the 12 poles forms a single permanent magnet group, or if as Figure 1 As shown, each pole 12 forms two permanent magnet groups, and the radially outwardly diverging permanent magnets (i.e., in the case of several permanent magnet groups, the permanent magnets of the inner permanent magnet group) or the recesses receiving the permanent magnets form a first angle α1, which is particularly between 70° and 140°, preferably between 80° and 135°, and particularly preferably between 45° and 130°. Figure 1 In the middle, the radially outwardly diverging permanent magnets of the outer permanent magnet assembly or the recessed portion 18 receiving the permanent magnets form a second angle α2, which is particularly between 80° and 175°, preferably between 90° and 175°, and particularly preferably between 100° and 175°, wherein in Figure 1 In the middle, the second angle α2 is greater than the first angle α1.

[0037] Preferably, the rotor 10 of the motor 11 includes two to five pole pairs. The outer diameter D of the rotor base 16 R,A Especially between 90mm and 170mm, preferably between 110mm and 170mm, and particularly preferably between 120mm and 170mm. The inner diameter D of the rotor base 16 R,I Especially between 10mm and 110mm, preferably between 30mm and 80mm, and particularly preferably between 40mm and 80mm.

[0038] Figure 2 A variation of the motor according to the invention is shown, wherein the shaped radially inner recesses 17 arranged in a V-shape relative to each other are subdivided into two sections 17a and 17b, namely an inner section 17a and an outer section 17b, wherein the inner section 17a or the magnets 19a contained in the inner section 17a form an angle α1, and the outer section 17b or the permanent magnets 19b contained in the outer section form a third angle α3. The first angle α3 is smaller than the first angle α1. The first angle α1 and the third angle α3 are... Figure 1 The implementation scheme is for movement within the angular range indicated by angle α1.

[0039] Regarding all other details Figure 2The exemplary embodiments of the application are in accordance with the exemplary embodiments of the application, such that in order to avoid unnecessary repetition of the Figure 1 The exemplary embodiments of the application are in accordance with the exemplary embodiments of the application, such that in order to avoid unnecessary repetition of the Figure 2 The exemplary embodiments of the application are in accordance with the exemplary embodiments of the application, such that in order to avoid unnecessary repetition of the Figure 1 The exemplary embodiments of the application are in accordance with the exemplary embodiments of the application, such that in order to avoid unnecessary repetition of the

[0040] The present application provides a rotor of an electric machine, by means of which the electric machine can provide high power, thus high torque, at high maximum speed, thus at high maximum circumferential or surface speed. The electric machine is designed as a power device of a motor vehicle, i.e. a hybrid vehicle or an electric vehicle.

Claims

1. A rotor (10) of an electric machine (11) designed as a permanent-magnet synchronous electric machine, wherein the rotor (10) comprising a rotor base body (16) having radially outwardly open pocket-like recesses (17, 17a, 17b, 18) and permanent magnets (19, 19a, 19b, 20) positioned in the recesses (17, 17a, 17b, 18), wherein the rotor (10) has poles (12) which are arranged next to one another alternately and form pole pairs, viewed in the circumferential direction, wherein in the region of each pole (12) there is respectively designed at least one permanent-magnet group comprising permanent magnets (19, 19a, 19b, 20) arranged in V- shaped positioned recesses (17, 17a, 17b, 18), which permanent magnets diverge radially outwardly, wherein the radially outer end of the permanent magnets (19, 19b, 20) arranged in V- shaped positioned recesses (17, 17b, 18) has an outer surface (23, 24) with a chamfer (25, 26) which extends in the tangential direction of the outer circumference of the rotor base body (16) or parallel thereto at the respective circumferential position of the respective radially outer end of the respective permanent magnet (19, 19b, 20), which radially outer end extends adjacent to the outer circumference of the rotor base body (16), wherein the rotor base body (16) supports a clamping element (27) on the outer circumference.

2. The rotor (10) according to claim 1, characterized in that The chamfer (25, 26) at the radially outer end of the respective permanent magnet (19, 19b, 20) is radially inwardly offset and parallel to the tangential direction at a distance from the outer circumference of the rotor base body (16) ag The distance is 0.1 mm to 6 mm, preferably 0.2 mm to 5 mm, particularly preferably 0.5 mm to 3.5 mm.

3. The rotor (10) according to claim 1, characterized in that The chamfer (25, 26) extends tangentially to the outer circumference of the rotor base body (16) at the radially outer end of the respective permanent magnet (19, 19b, 20).

4. The rotor (10) according to any one of claims 1 to 3, characterized in that The radially inner end of the permanent magnets (19, 19a, 20) arranged in V- shaped positioned recesses (17, 17a, 18) has an outer surface (28, 29) with a chamfer (30, 31) which extends in the direction of or parallel to the d-axis (21) of the respective pole (12), which radially inner end extends adjacent to the d-axis (21) of the respective pole (12) of the rotor.

5. The rotor (10) according to claim 4, characterized in that The radially inner end of the permanent magnets (19, 19a, 20) arranged in the recesses (17, 17a, 18) contacts the permanent-magnet group of the respective pole (12).

6. The rotor (10) according to claim 4, characterized in that distance d of the radially inner end of the permanent magnets (19, 19a, 20) of the permanent magnet group arranged in the recesses (17, 17a, 18) center maximally 10 mm, preferably maximally 5 mm, particularly preferably maximally 3 mm.

7. The rotor (10) according to any one of claims 1 to 6, characterized in that In the region of each pole (12) there is respectively configured at least two permanent-magnet groups formed by permanent magnets (19, 19a, 19b, 20) arranged in V- shaped positioned recesses (17, 17a, 17b, 18).

8. The rotor (10) according to any one of claims 1 to 7, characterized in that At the respective permanent-magnet group of the respective pole (12), or in the case of at least two permanent-magnet groups per pole (12) at the inner permanent-magnet group of the respective pole (12), the radially outwardly diverging permanent magnets (19, 19a, 19b) of the respective permanent-magnet group enclose a first angle, which is between 70° and 140°, preferably between 80° and 135°, particularly preferably between 85° and 130°.

9. The rotor (10) according to claim 8, characterized in that In the case of at least two permanent magnet groups per pole (12), at the outer permanent magnet group of the respective pole, the radially outwardly diverging permanent magnets (20) of the respective permanent magnet group enclose a second angle, which is between 80° and 175°, preferably between 90° and 175°, particularly preferably between 100° and 175°.

10. Rotor (10) according to any of claims 1 to 9, characterized in that The outer diameter D of the rotor base body (10) R,A The inner diameter D of the rotor base body (10) is between 90 mm and 170 mm, preferably between 110 mm and 170 mm, particularly preferably between 120 mm and 170 mm R,I between 10 mm and 110 mm, preferably between 30 mm and 80 mm, particularly preferably between 40 mm and 80 mm.

11. The rotor (10) according to any one of claims 1 to 10, characterized in that the rotor has two pole pairs to five pole pairs.

12. Electric machine (11) having a rotor (10) according to any of claims 1 to 11, the electric machine being designed as a power device of a motor vehicle, i.e. of a hybrid vehicle or of an electric vehicle.

13. Motor vehicle (100), i.e. hybrid vehicle or electric vehicle, having an electric machine (11) as a power device, the electric machine comprising a rotor (10) according to any of claims 1 to 11.

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