Stator for an electric machine and electric machine for driving a vehicle

Abstract

A stator (1) for an electric motor (51) is disclosed, wherein the stator (1) has distributed stator windings (2) and a stator core (3), the distributed stator windings having N phase windings and P pole pairs, and slots (A) formed in the stator core, wherein the stator windings (2) are arranged in the slots (A); wherein the stator core (3) is divided into 2×P×N winding regions (8a-f) that are uniformly and successively arranged in the circumferential direction, and the stator core has a large number of recesses (4a-l), the recesses (4a-l) being formed in at least one arrangement (5a-c) of recesses (4a-d, 4e-f, 4i-l) that are successively arranged in the circumferential direction, and at least two recesses (4a-d, 4e-f, 4i-l) of the arrangement (5a-c) belonging to the winding region (8a-f). A winding region in the circumferential direction; wherein each pair of recesses (4a-d, 4e-h, 4i-l) that are adjacent in the circumferential direction and belong to the same winding region (8a-f) has a first angular spacing (11a-c, 15a-c, 20a-c) relative to each other in the circumferential direction; wherein each pair of recesses (4a, 4d, 4e, 4h, 4i, 4l) that are adjacent in the circumferential direction and belong to different winding regions (8a-f) has a second angular spacing (11d, 15d, 20d) relative to each other in the circumferential direction; and in at least one arrangement (5a-c), the first angular spacing (11a-c, 15a-c, 20a-c) and the second angular spacing (11d, 15d, 20d) are different, such that the arrangement (5a-c) is in a non-uniform arrangement form.

Description

Technical Field

[0001] This invention relates to a stator for an electric motor, wherein the stator has distributed stator windings and a stator core, the distributed stator windings having N phase windings and P pole pairs, slots formed in the stator core, wherein the stator windings are arranged in the slots; wherein the stator core is divided into 2×P×N winding regions that are uniformly and successively arranged in the circumferential direction; wherein the stator core has a large number of recesses that extend axially from a first end face of the stator core to a second end face of the stator core opposite to the first end face; wherein these recesses are formed in at least one arrangement of recesses that are successively arranged in the circumferential direction, and at least two recesses in this arrangement belong to one winding region; wherein each pair of recesses that are adjacent in the circumferential direction and belong to the same winding region has a first angular spacing relative to each other in the circumferential direction; wherein each pair of recesses that are adjacent in the circumferential direction and belong to different winding regions has a second angular spacing relative to each other in the circumferential direction.

[0002] In addition, the present invention relates to an electric motor for driving a vehicle. Background Technology

[0003] Document US2015 / 0381000 A1 discloses a stator for a rotating electric machine, the stator comprising: an annular stator core having a plurality of paired slots for a first phase, a plurality of paired slots for a second phase, and a plurality of paired slots for a third phase, the slots being arranged sequentially and repeatedly in a circumferential direction; and stator windings including windings for the first phase, windings for the second phase, and windings for the third phase, the windings being arranged on the stator core for reception in corresponding slots. The portions of the stator windings received in the slots are radially stacked in four layers.

[0004] Article by I. Petrov, P. Ponomarev, and J. Pyrhonen: “Reducing Torque Ripple in a 12-Slot 10-Pole Fractional-Slot Permanent Magnet Synchronous Motor with Non-Overlapping Windings by Achieving Unequal Stator Tooth Widths,” International Conference on Electrical Engineering (ICEM), pp. 1455-1460, 2014; Article by I. Petrov, P. Ponomarev, Y. Alexandrova, and J. Pyrhonen: “Unequal Tooth Widths for Reducing Torque Ripple in Permanent Magnet Synchronous Motors with Fractional-Slot Non-Overlapping Windings,” Proceedings of the IEEE Magnetics Society (IEEE). Trans. Magn), Vol. 51, No. 2, pp. 1-9, 2015; and P. Ponomarev, I. Petrov and J. Pyrhonen’s article “Reducing Torque Fluctuations in Double-Layer 18 / 16TC-PMSM by Adjusting Tooth Width to Minimize Local Saturation”, International Conference on Electrical Engineering (ICEM), pp. 1461-1467, 2014, each discloses a stator with concentrated toothed coil windings and unequal stator tooth widths.

[0005] In a stator with distributed stator windings (which are received in slots arranged uniformly in the circumferential direction), parasitic forces are generated during the operation of the motor. This can result in large torque fluctuations, which lead to undesirable vibrations and operating noise. Summary of the Invention

[0006] The object of this invention is to provide a method for making an electric motor with a stator that has distributed stator windings operate more quietly.

[0007] According to the invention, this objective is achieved by a stator of the type mentioned in the introduction, wherein, in at least one arrangement, the first angular spacing and the second angular spacing are different, such that the arrangement is in the form of a non-uniform arrangement.

[0008] The stator for the motor has distributed stator windings. The stator windings have N phase windings. The stator has P pole pairs. The stator has a stator core. Slots are formed in the stator core. The stator windings are arranged in the slots. The stator core is divided into 2×P×N winding regions. The winding regions are uniformly successive to each other in the circumferential direction. The stator core has a large number of recesses. The recesses extend axially from a first end face of the stator core to a second end face of the stator core. The second end face is opposite to the first end face. The recesses are formed in at least one arrangement of recesses successive to each other in the circumferential direction. At least two recesses in this arrangement belong to one winding region. Each pair of recesses adjacent in the circumferential direction and belonging to the same winding region has a first winding spacing relative to each other in the circumferential direction. Each pair of recesses adjacent in the circumferential direction and belonging to different winding regions has a second winding spacing relative to each other in the circumferential direction. In at least one arrangement, the first winding spacing and the second winding spacing are different, such that the arrangement is non-uniform.

[0009] In particular, the stator according to the invention is characterized in that the recesses extending in the axial direction are not arranged uniformly in at least one arrangement in the circumferential direction, but are shifted relative to the corresponding winding regions, such that the second winding spacing of the pairs of recesses adjacent in the circumferential direction and belonging to different winding regions is different. Therefore, the occurrence of parasitic forces during motor operation can be greatly reduced because the cogging torque, which increases trigger torque fluctuations, is reduced. This advantageously allows the motor to operate more quietly, particularly with reduced vibration and noise, without any substantial disadvantage in terms of its performance.

[0010] The stator core is preferably in the form of a lamination assembly. The recesses typically extend axially parallel to the longitudinal axis of the stator core. Preferably, N = 3 or an integer multiple of 3. More preferably, P equals 2, 4, 6, or 8. In at least one arrangement, for each m ≥ 2, particularly m = 2, 3, or 4, the recess preferably belongs to one winding region within the winding region. Preferably, the recesses in the corresponding arrangements have the same shape when viewed from the first end face.

[0011] The first angular spacing is preferably defined as the difference between the angular positions of a pair of adjacent recesses belonging to the same winding region. The second angular spacing is preferably defined as the difference between the angular positions of a pair of adjacent recesses belonging to different winding regions. When viewed from the first end face, the angular position of the corresponding recess can be defined as the angular position of the radial tangent at the edge of the recess.

[0012] Preferably, in a non-uniform arrangement, the first angular spacing of a corresponding pair of adjacent recesses is the same. In the case of multiple non-uniform arrangements, the second angular spacing is preferably the same. The second angular spacing can be less than or greater than the first angular spacing. In particular, the second angular spacing can be at least 360° / (2×P×N×m×20) smaller or larger than the first angular spacing, preferably at least 360° / (2×P×N×m×10).

[0013] Preferably, the recesses in the first arrangement, which are non-uniformly distributed, form the groove. Therefore, the groove can be formed using the displacement molding provided according to the invention to allow for quieter operation.

[0014] Alternatively, the recesses in the first arrangement can form grooves and be regularly arranged in the circumferential direction of the entire stator core.

[0015] Preferably, the stator according to the invention has a receiving space for the rotor of the motor. Furthermore, the stator core may have a covering surface facing the receiving space. Preferably, the covering surface is a radially inner covering surface of the stator core, which specifically defines the air gap between the stator and rotor in the motor.

[0016] In an advantageous embodiment, the recesses of the second arrangement may extend through the covering surface. Preferably, the number of recesses in the second arrangement corresponds to the number of recesses in the first arrangement. In particular, the number of recesses in the first arrangement belonging to the corresponding area of ​​the winding region corresponds to the number of recesses in the second arrangement belonging to the corresponding area of ​​the winding region.

[0017] The recess in the second arrangement can form a slot opening in the stator core that connects the slot to the receiving space. This allows for the construction of an open slot in the stator. Alternatively, the recess in the second arrangement can form a pseudo-slot opening in the stator core that forms a blind hole in the radial direction. In this case, the recess in the second arrangement can be completely separated from the slot by the stator core. Therefore, a closed slot with an associated pseudo-slot can be constructed, which allows for a particularly advantageous flux path in the stator core.

[0018] The recesses in the second arrangement are preferably located at the angular positions where they overlap with the grooves in the circumferential direction. In this case, if the recesses in the second arrangement form groove openings, they can form a continuous radial connection from the receiving space to the corresponding groove. If the recesses in the second arrangement form pseudo-groove openings, each recess in the second arrangement can be located on a radial line extending through one of the grooves.

[0019] Typically, the recess in the second arrangement has a smaller range in the circumferential direction than the groove.

[0020] It can be provided that the second arrangement is non-uniform. This allows for quieter operation, independent of the slot displacement forming. Alternatively, the recesses of the second arrangement can be regularly arranged in the circumferential direction of the entire stator core.

[0021] Furthermore, the recesses in the third arrangement can extend through the covering surface. Preferably, the number of recesses in the third arrangement corresponds to the number of recesses in the first arrangement and / or the number of recesses in the second arrangement. In particular, the number of recesses in the corresponding areas of the winding region in the first arrangement and / or the number of recesses in the corresponding areas of the winding region in the second arrangement corresponds to the number of recesses in the corresponding areas of the winding region in the third arrangement.

[0022] Advantageously, the recesses in the third arrangement can be positioned circumferentially at angular locations between the angular positions of adjacent slots in the corresponding pair. In particular, the radial lines extending through the respective recesses in the third arrangement do not extend through one of the slots.

[0023] The third arrangement of recesses can form pseudo-groove openings that create blind holes in the radial direction.

[0024] Preferably, the third arrangement is non-uniformly distributed. Alternatively, the recesses of the third arrangement can be regularly distributed along the circumferential direction of the entire stator core.

[0025] In the stator according to the invention, it can be further provided that the stator core can be divided into first to second × P × N sectors for a corresponding arrangement, wherein each sector is divided into first to m partial sectors, where m corresponds to the number of recesses belonging to one winding region in the corresponding arrangement, wherein for every 1 ≤ j ≤ 2 × P × N and every 1 ≤ k ≤ m, the kth recess belonging to the jth sector is completely arranged in the kth partial sector of the jth sector, such that the outer boundary of the kth partial sector, when viewed from the first end face, in a clockwise direction is the tangent to the edge of the kth recess. In this case, the first to (m-1)th central angles of the first to (m-1)th partial sectors can correspond to a first angular spacing, and the mth central angle of the mth partial sector can correspond to a second angular spacing. Preferably, each sector precisely comprises one winding region. Typically, sectors, partial sectors, and recesses are indicated in their circumferential order.

[0026] In a non-uniform arrangement, the m-th central angle can be different from the first to (m-1)-th central angles. If the recesses are arranged regularly in the circumferential direction of the entire stator core, then the first to m-th central angles can be the same.

[0027] In the stator according to the invention, it is further preferred that slots form receiving spaces for a predetermined number of shaped conductors, the stator windings being formed from shaped conductors. So-called hairpin windings can be formed from shaped conductors. The shaped conductors are preferably formed from bent conductive rods, particularly conductive rods made of copper. Typically, a predetermined number of shaped conductors, between four and twelve, are received inside the corresponding slots. This number of shaped conductors can fill the cross-sectional surface area of ​​the recesses at a rate of at least 60%, preferably at least 80%, particularly preferably at least 90%. The shaped conductors typically have a rectangular cross-section, which is rounded where applicable. However, alternatively, the stator windings can also be formed from wound wire, particularly wound wire with a circular cross-section.

[0028] The basic objective of the invention is further achieved by an electric motor for driving a vehicle, the motor comprising a stator according to the invention and a rotor rotatably supported within the stator. The motor is preferably a synchronous motor or an asynchronous motor. The rotor may be a permanently excited rotor. In particular, the motor is configured to form part of the drivetrain of a vehicle. The vehicle may be a battery electric vehicle (BEV) or a hybrid vehicle. Attached Figure Description

[0029] Additional advantages and details of the invention will be understood from the embodiments described below with reference to the accompanying drawings. These drawings are schematic illustrations, in which:

[0030] Figure 1 A schematic diagram of the constant is shown;

[0031] Figure 2 and Figure 3 Each shows a cross-section of a first embodiment of the stator according to the present invention;

[0032] Figures 4 to 7 Each shows a cross-section of an additional embodiment of the stator according to the invention;

[0033] Figure 8 and Figure 9 Each shows a cross-section of the cutout portion according to an additional embodiment of the stator of the present invention;

[0034] Figure 10 A graph showing the torque versus the rotor angular position during operation of an embodiment of the stator according to the invention, compared to a conventional stator; and

[0035] Figure 11 A basic diagram of a vehicle having an exemplary embodiment of an electric motor according to the present invention is shown. Detailed Implementation

[0036] Figure 1 A cross-section of the constant 101 is shown.

[0037] Stator 101 includes an N-phase (N=3) distributed stator winding 102 and a stator core 103. The distributed stator winding forms a stator pole pair (P=1). The stator core has a plurality of recesses 104a-h formed therein, which extend axially from a first end face to a second end face of the stator core 103 opposite to the first end face. The view direction of the first end face is directed according to… Figure 1 The cross-section of the recesses 104a-h forms a first arrangement 105a of the recesses 104a-d and a second arrangement 105b of the recesses 104e-h. The recesses 104a-d of the first arrangement 105a form slots for receiving the stator winding 102. The recesses 104e-h of the second arrangement 105b form slot openings that connect the recesses 104a-d of the first arrangement 105a to the receiving space 106 for the rotor by extending through the inner cover surface 107 of the stator core 103.

[0038] The stator core is divided into six (2×P×N) winding regions 108a-f, which are uniformly arranged in the circumferential direction and follow each other. In the recesses 104a-d and 104e-h of the corresponding arrangements 105a and 105b, m = 4 recesses belong to one of the winding regions 108a-f.

[0039] In the first arrangement 105a, each pair of recesses 104a-d that are adjacent in the circumferential direction and belong to the same winding region 108a-f have a first angular distance 111a-c relative to each other in the circumferential direction. Furthermore, each pair of recesses 104a, 104d that are adjacent in the circumferential direction and belong to different winding regions 108a-f have a second angular distance 111d relative to each other in the circumferential direction. The first angular distance and the second angular distance are the same, such that the recesses 104a-d are arranged regularly in the circumferential direction throughout the stator core 103.

[0040] Therefore, for the first arrangement 105a, the stator core 103 can be divided into first to sixth (2×P×N) sectors 109a-f, which are in Figure 1 The solid radial arrows indicate this. The corresponding sectors 109a-f are further divided into the first to fourth (m-th) sub-sectors 110a-d, which are located in... Figure 1The first sector 109a is shown by a radial dashed line. For every 1 ≤ j ≤ 6 = 2 × P × N and every 1 ≤ k ≤ m = 4, the kth recesses 104a-d belonging to the j-th sector 109a-f are completely arranged in the kth partial sector 110a-d of the j-th sector 109a-f, such that when viewed from the first end face in a clockwise direction, the outer boundary of the kth partial sector 110a-d is the tangent to the edge of the kth recess 104a-d. In this case, the central angle of the corresponding partial sector 110a-d corresponds to and is the same as the first and second angular distances 111a-d, such that all recesses 104a-d are arranged at equal intervals in the circumferential direction.

[0041] In a similar manner, the recesses 104e-h of the second arrangement 105b are also regularly arranged in the circumferential direction of the stator core 103.

[0042] Figure 2 and Figure 3 Cross-sections of the first embodiment of stator 1 are shown.

[0043] The stator 1 includes an N-phase (N=3) distributed stator winding 2 and a stator core 3. The distributed stator winding forms a pole pair (P=1) of the stator 1. The stator core has a large number of recesses 4a-h formed therein. These recesses extend axially from a first end face to a second end face of the stator core 3 opposite to the first end face. The view direction of the first end face is oriented according to... Figure 2 The cross-section. Recesses 4a-h form a first arrangement 5a of recesses 4a-d and a second arrangement 5b of recesses 4e-h. In this case, the recesses 4a-d of the first arrangement 5a form slots A for receiving the stator winding 2. The recesses 4e-h of the second arrangement 5b form slot openings B, which connect the recesses 4a-d of the first arrangement 5a to the rotor 52 (see) by extending through the inner cover surface 7 of the stator core 3. Figure 11 ) receiving space 6.

[0044] The stator core is divided into six (2×P×N) winding zones 8a-f, which are uniformly arranged sequentially in the circumferential direction. In the recesses 4a-d and 4d-h with corresponding arrangements of 5a and 5b, m = 4 recesses belong to one of the winding zones 8a-f.

[0045] In the first arrangement 5a, each pair of recesses 4a-d that are adjacent in the circumferential direction and belong to the same winding region 8a-f have a first angular distance 11a-c relative to each other in the circumferential direction. Furthermore, each pair of recesses 4a, 4d that are adjacent in the circumferential direction and belong to different winding regions 8a-f have a second angular distance 11d relative to each other in the circumferential direction. The first angular distance 11a-c and the second angular distance 11d are different, making the first arrangement 5a a non-uniform arrangement.

[0046] In this embodiment, the second angular spacing 11d is smaller than the first angular spacing 11a-c. The first angular spacing 11a-c of the paired recesses 4a-d that are adjacent in the circumferential direction and belong to the same winding region 8a-f is the same. The corresponding first angular spacing 11a-c is greater than 360° / (2×P×N×m), while the second angular spacing 11d is less than 360° / (2×P×N×m).

[0047] like Figure 3 As detailed in the diagram, in the second arrangement 5b, each pair of recesses 4e-h that are adjacent in the circumferential direction and belong to the same winding region 8a-f have a first angular distance 15a-c relative to each other in the circumferential direction. Furthermore, each pair of recesses 4e, 4h that are adjacent in the circumferential direction and belong to different winding regions 8a-f have a second angular distance 15d relative to each other in the circumferential direction. The first angular distance 15a-c and the second angular distance 15d are different, making the second arrangement 5b a non-uniform arrangement.

[0048] In this embodiment, the second angular spacing 15d is smaller than the first angular spacing 15a-c. The first angular spacing 15a-c of the paired recesses 4e-h that are adjacent in the circumferential direction and belong to the same winding region 8a-f is the same. The corresponding first angular spacing 15a-c is greater than 360° / (2×P×N×m), while the second angular spacing 15d is less than 360° / (2×P×N×m).

[0049] Furthermore, in the first embodiment, the first and second angular spacings 11a-d of the first arrangement 5a correspond to the first and second angular spacings 15a-d of the second arrangement 5b, such that the slot opening B formed by the recesses 4e-h is located at the same relative position to the slot A formed by the recesses 4a-d. In this case, the slot opening B is centered relative to the slot A.

[0050] Therefore, for the first arrangement 5a, the stator core 3 can be divided into the first to sixth (2×P×N) sectors 9a-f, which are in Figure 2 The solid radial arrows indicate this. The corresponding sectors 9a-f are further divided into the first to fourth (m-th) sub-sectors 10a-d, which are located in... Figure 2The first sector 9a is shown by a radial dashed line. For every 1 ≤ j ≤ 6 = 2 × P × N and every 1 ≤ k ≤ m = 4, the k-th recesses 4a-d belonging to the j-th sector 9a-f are completely arranged in the k-th partial sector 10a-d of the j-th sector 9a-f, such that when viewed clockwise from the first end face, the outer boundary of the k-th partial sector 10a-d is the tangent to the edge of the k-th recess 4a-d. In this case, the first to third [(m-1)] central angles of the first to third [(m-1)] partial sectors 10a-c correspond to the first angular spacing 11a-c and are the same. On the one hand, the first to third [(m-1)] central angles, and on the other hand, the fourth central angle of the fourth (m) partial sector 10d corresponding to the second angular spacing 11d, are different. In this embodiment, the fourth central angle is smaller than the corresponding angle among the first to third central angles.

[0051] Furthermore, for the second arrangement 5b, the stator core 3 can be divided into the first to sixth (2×P×N) sectors 13a-f, these sectors in Figure 3 The solid radial arrows indicate this. The corresponding sectors 13a-f are further divided into first to fourth (m-th) sub-sectors 14a-d, which are further subdivided into... Figure 3 The first sector 13a is shown by a radial dashed line. For every 1 ≤ j ≤ 6 = 2 × P × N and every 1 ≤ k ≤ m = 4, the kth recess 4e-h belonging to the j-th sector 13a-f is completely arranged in the kth part sector 14a-d of the j-th sector 13a-f, such that when viewed clockwise from the first end face, the outer boundary of the kth part sector 14a-d is the tangent to the edge of the kth recess 4e-h. In this case, the first to third [(m-1)] central angles of the first to third [(m-1)] part sectors 14a-c correspond to the first angular spacing 15a-c and are the same. On the one hand, the first to third [(m-1)] central angles, and on the other hand, the fourth central angle of the fourth (m) part sector 14d corresponding to the second angular spacing 15d are different. In this embodiment, the fourth central angle is smaller than the corresponding angle among the first to third central angles.

[0052] Furthermore, in this embodiment, the central angle 11a-d of the first arrangement 5a corresponds to the central angle 15a-d of the second arrangement 5b.

[0053] As an example, stator 1 has a number of four (m=4) holes, wherein the number of holes corresponds to the number of recesses 4a-d and 4e-h belonging to the corresponding winding regions 8a-f in the corresponding arrangements 5a and 5b.

[0054] As an example, stator winding 2 consists of a large number of shaped conductors 16 (see...). Figure 2This is formed such that the stator winding 2 is a hairpin winding. For example, six shaped conductors 16 are arranged in each recess 4a-d of the first arrangement 5a.

[0055] An additional embodiment of the stator 1 is described below. Except for the differences described below, this additional embodiment of the stator corresponds to the stator 1 according to the first embodiment. Here, the same or functionally equivalent parts have the same reference numerals.

[0056] Figure 4 A cross-section of a second embodiment of stator 1 is shown.

[0057] According to the second embodiment, in the first arrangement 5a, the second corner spacing 11d is greater than the first corner spacing 11a-c. In this case, the first corner spacing 11a-c is less than 360° / (2×P×N×m), while the second corner spacing 11d is greater than 360° / (2×P×N×m). Similarly, in the second arrangement 5b, the second corner spacing 15d (not shown) is greater than the first corner spacing 15a-c (not shown). In this case, the first corner spacing 15a-c is less than 360° / (2×P×N×m), while the second corner spacing 15d is greater than 360° / (2×P×N×m).

[0058] Figure 5 A cross-section of a third embodiment of the stator 1 is shown, which corresponds to the second embodiment, wherein the first angular spacing 11a-c, 15a-c or the first to third central angles are substantially greater than the second angular spacing 11d, 15d or the fourth central angle (the first and second angular spacings 15a-d are not shown).

[0059] Figure 6 A cross-section of a fourth embodiment of stator 1 is shown.

[0060] According to the fourth embodiment, in the first arrangement 5a, the first and second corner spacings 11a-d (not shown) are the same, so that the first arrangement 5a is not formed as a non-uniform arrangement. The recesses 4a-d of the first arrangement 5a forming the groove A are regularly arranged in the circumferential direction of the entire stator core 3.

[0061] In the second arrangement 5b, as in the first embodiment, the second angular spacing 15d is smaller than the first angular spacing 15a-c. Therefore, the recesses 4e-h forming the groove opening B are located at different relative positions to the recesses 4a-d forming the groove A.

[0062] Figure 7 A cross-section of a fifth embodiment of the stator 1 is shown. Except for the following differences, the fifth embodiment corresponds to the second embodiment.

[0063] In the third embodiment, a third arrangement 5c is provided with recesses 4i-l in the form of pseudo-groove openings C. The recesses 4i-l extend through the covering surface 7 and are arranged in the circumferential direction between positions of a corresponding pair of adjacent recesses 4a-d in the first arrangement 5a, or between positions of a corresponding pair of adjacent recesses 4e-h in the second arrangement 5b. The third arrangement 5c is non-uniformly arranged, wherein the second angular spacing 20d is greater than the first angular spacing 20a-c.

[0064] Furthermore, for the third arrangement 5c, the stator core 3 can be divided into the first to sixth (2×P×N) sectors 18a-f, these sectors in Figure 7 The solid radial arrows indicate this. The corresponding sectors 18a-f are further divided into first to fourth (m-th) sub-sectors 19a-d, which are further subdivided into... Figure 3 The first sector 18a is shown by a radial dashed line. For every 1 ≤ j ≤ 6 = 2 × P × N and every 1 ≤ k ≤ m = 4, the kth recess 4i-l belonging to the j-th sector 18a-f is completely arranged in the kth part sector 19a-d of the j-th sector 18a-f, such that when viewed clockwise from the first end face, the outer boundary of the kth part sector 19a-d is the tangent to the edge of the kth recess 4i-l. In this case, the first to third [(m-1)] central angles of the first to third [(m-1)] part sectors 19a-c correspond to the first angular spacing 20a-c and are the same. On the one hand, the first to third [(m-1)] central angles, and on the other hand, the fourth central angle of the fourth (m) part sector 19d corresponding to the second angular spacing 20d, are different. In this embodiment, the fourth central angle is larger than the corresponding angle among the first to third central angles.

[0065] Alternatively, according to another embodiment, the second corner spacing 20d may be smaller than the first corner spacing 20a-c.

[0066] Figure 8 A cross-section of the cutout portion of the stator 1 according to the sixth embodiment is shown. The description related to the fifth embodiment can be applied to the sixth embodiment of the stator.

[0067] In the stator 1 according to the sixth embodiment, in each arrangement 5a-c, only m = 2 recesses 4a, 4b, 4e, 4f, 4i, 4j belong to each winding region 8a, 8b, 8c. The number of pole pairs P is, for example, 4, 6, or 8. The number of holes in the stator 1 is m = 2. In this case, the arrangements 5a, 5c are non-uniformly arranged. Accordingly, the first and second center angles of the corresponding sectors 9a, 9b, 9c, 18a, 18b, 18c are different. In the second arrangement 5b, the recesses 4e-h are regularly arranged in the circumferential direction of the entire stator core 3. Accordingly, the first and second center angles of the corresponding sectors 13a, 13b, 13c are different.

[0068] Figure 9 A cross-section of a seventh embodiment of the stator 1 is shown, corresponding to the sixth embodiment, wherein the recesses 4a and 4b of the first arrangement 5a form a closed groove A separated from the receiving space 6 by the stator core 3. Furthermore, the recesses 4e and 4f of the second arrangement 5b form a pseudo-groove opening D.

[0069] Figure 10 The diagram shows the torque M relative to the rotor 52 (see figure) during operation of an embodiment of stator 1, compared to a conventional stator 100 (shown as dashed lines). Figure 11 ) angular position The curve is shown as a solid line. It can be seen that the torque fluctuation in stator 1 with the shift sector is significantly smaller than the torque fluctuation in conventional stator 100.

[0070] Figure 11 This is a schematic diagram of an exemplary embodiment of a vehicle 50, which has an exemplary embodiment of a motor 51.

[0071] The motor 51 has a stator 1 according to one of the embodiments described above and a rotor 52 rotatably supported inside the stator 1. The motor 51 is, in particular, a permanently excited synchronous or asynchronous motor and is configured to drive the vehicle 50. The motor 51 is therefore part of the drivetrain 53 of the vehicle 50. The vehicle 50 may be a battery electric vehicle (BEV) or a hybrid vehicle.

Claims

1. A stator (1) for an electric motor (51), wherein, The stator (1) has distributed stator windings (2) and a stator core (3). The distributed stator windings have N phase windings and P pole pairs. The stator core has slots (A) formed therein, wherein the stator windings (2) are arranged in the slots (A); wherein, The stator core (3) is divided into 2×P×N winding regions (8a-f) that are uniformly arranged in the circumferential direction and follow each other, wherein, The stator core (3) has a large number of recesses (4a-l), which extend axially from a first end face of the stator core (3) to a second end face of the stator core (3) opposite to the first end face; wherein, The recesses (4a-l) are formed in at least one arrangement (5a-c) of successive recesses (4a-d, 4e-f, 4i-l) in the circumferential direction, and at least two recesses (4a-d, 4e-f, 4i-l) in the arrangement (5a-c) belong to one of the winding regions (8a-f); wherein, Each pair of recesses (4a-d, 4e-h, 4i-l) that are adjacent in the circumferential direction and belong to the same winding region (8a-f) has a first angular spacing (11a-c, 15a-c, 20a-c) relative to each other in the circumferential direction; wherein, Each pair of recesses (4a, 4d, 4e, 4h, 4i, 4l) that are adjacent in the circumferential direction and belong to different winding regions (8a-f) have a second angular spacing (11d, 15d, 20d) relative to each other in the circumferential direction. Its features are, In at least one arrangement (5a-c), the first angular spacing (11a-c, 15a-c, 20a-c) and the second angular spacing (11d, 15d, 20d) are different, such that the arrangement (5a-c) is in a non-uniform arrangement.

2. The stator as claimed in claim 1, wherein, The groove (A) is formed by the recesses (4a-d) of the first arrangement (5a) which are arranged in a non-uniform manner.

3. The stator as described in claim 1, wherein, The recesses (4a-d) of the first arrangement (5a) form the groove (A) and are regularly arranged in the circumferential direction of the entire stator core (3).

4. The stator as described in any of the preceding claims, wherein, The stator (1) has a receiving space (6) for the rotor (52) of the motor (51), and the stator core (3) has a covering surface (7) facing the receiving space (6).

5. The stator as described in claim 4, wherein, The recess (4e-h) of the second arrangement (5b) extends through the covering surface (7).

6. The stator as described in claim 5, wherein, The recess (4e-h) of the second arrangement (5b) forms a slot opening (B) of the stator core (3) that connects the slot (A) to the receiving space (6), or forms a pseudo slot opening (D) of the stator core (3) that forms a blind hole in the radial direction.

7. The stator as described in claim 5 or 6, wherein, The recess (4e-h) of the second arrangement (5b) is arranged in the circumferential direction at the corner position where the recess overlaps with the groove (A).

8. The stator as claimed in any one of claims 5 to 7, wherein, The second arrangement (5b) is in the form of a non-uniform arrangement.

9. The stator according to any one of claims 5 to 7, wherein, The recesses of the second arrangement (5b) are regularly arranged in the circumferential direction of the entire stator core (3).

10. The stator according to any one of claims 4 to 9, wherein, The recess (4i-l) of the third arrangement (5c) extends through the covering surface (7).

11. The stator as claimed in claim 10, wherein, The recess (4i-l) of the third arrangement (5c) is arranged in the circumferential direction at an angular position between the angular positions of a corresponding pair of adjacent slots (A).

12. The stator as claimed in claim 10 or 11, wherein, The recess of the third arrangement (5c) forms a pseudo-groove opening (C) that forms a blind hole in the radial direction.

13. The stator according to any one of claims 10 to 12, wherein, The third arrangement (5c) is in a non-uniform arrangement form.

14. The stator according to any one of claims 10 to 12, wherein, The recesses (4i-l) of the third arrangement (5c) are regularly arranged in the circumferential direction of the entire stator core (3).

15. An electric motor (51) for driving a vehicle (50), the electric motor comprising a stator (1) as described in any of the preceding claims and a rotor (52) rotatably supported inside the stator (1).

Images