Stator having a winding assembly, in particular a distributed winding assembly, for an electric motor

Abstract

The invention relates to a stator (0) having a winding assembly (1), in particular a distributed winding assembly (1), for an electric motor, comprising a number N of slots (n i ) which are arranged regularly along the inner circumference (IU) of the stator (0) and each of which is delimited by a pair of adjacent teeth (z i , z i+ 1), wherein the winding assembly (1) comprises a first conductor strand (13) and a second conductor strand (24) per electrical phase (U, V, W); all of the conductor strands (13, 24) are wound onto the teeth (z i ) at a distance of slot pitch widths to one another, in each case in conductor track layers (l k ) that are mutually radially spaced within the slots (n i ), in order to induce a number 2P of magnetic poles (p j ) per phase (U, V, W) in the event of a current flow; and at a front layer jump portion (vLSA) protruding from the stator (0), layer jumps having a slot pitch width which differs from N / 2P are present only between precisely two adjacent poles (p 1, p 2) of a respective phase (U, V, W).

Description

[0001] Stator with a winding arrangement, in particular a distributed winding arrangement, for an electric motor

[0002] The invention relates to a stator with a winding arrangement, in particular a distributed winding arrangement, for an electric motor according to the independent claim.

[0003] The invention lies in the technical field of electric motors, in particular winding arrangements for stators.

[0004] The current-carrying conductor strands, wound into coils on the teeth of a stator and combined into electrical phases, generate a rotating magnetic field that drives the rotor of the electric motor. The way the conductor strands are wound and their properties are defined by the winding arrangement. In distributed winding arrangements, the conductor strands are not wound around one tooth each to form a coil, but rather have a slot pitch greater than one, meaning the conductor strands are each wound around several teeth to form a coil.

[0005] A conductor strand can be an electrically connected bundle of jointly contacted electrical conductors. However, to achieve a particularly high fill factor, it is common practice to use electrical conductors in the form of flat wires for conductor strands, as their rectangular cross-section allows them to fill the stator slots as tightly as possible. A special form is flat wires formed into so-called hairpins (for use as plug-in coils), i.e., into a U-shaped geometry reminiscent of a hairpin. Such hairpins have a (pointed) pin section, which allows hairpins to be placed next to each other particularly easily and in a space-saving manner.

[0006] The conductor strands lie within the slots on conductor track layers running concentrically around the stator's axis of rotation to form the turns of the coils in the winding arrangement. The current in a coil, which flows in opposite directions in two different slots, then creates a magnetic pole. The change of a conductor strand from one conductor track layer to another does not occur within the slots, but in layer jump sections that protrude from the stator at both ends (also called the winding head). The numerous and wide layer jumps that typically occur in distributed winding arrangements regularly create particularly large layer jump sections. However, the current flow within the layer jump sections does not contribute to the magnetic field that drives the rotor and instead causes detrimental Ohm losses.In order to save conductor material and to make the winding arrangements as compact as possible, it is therefore advantageous to find a winding arrangement which has the most compact layer jump sections possible.

[0007] However, in stators with known winding arrangements, especially known distributed winding arrangements, especially known distributed winding arrangements with hairpins as conductor strands, the layer jumps at the layer jump sections are designed in such a way that conductor strands often have to be arranged one above the other, and therefore the layer jump section is not very compact. This leads to waste of conductor strand material, increased ohmic resistance, and increased space requirements.

[0008] It is the object of the present invention to overcome the disadvantages of the prior art and in particular to provide a stator with a winding arrangement, in particular a distributed winding arrangement, for an electric motor, which allows the economical use of conductor strand material and provides compact layer jump sections.

[0009] This object is achieved by a stator with a winding arrangement, in particular a distributed winding arrangement, for an electric motor according to claim 1. Advantageous aspects of the invention form the subject matter of the dependent claims.

[0010] The invention comprises a stator with a winding arrangement, in particular a distributed winding arrangement, for an electric motor with a number of N slots n arranged regularly along an inner circumference of the stator, each of which is formed by two adjacent teeth z b z i+1are limited, wherein the winding arrangement comprises a first conductor strand and a second conductor strand per electrical phase, and wherein all conductor strands are each arranged in conductor track layers l spaced radially from one another within the slots rtt k by groove pitches spaced on the teeth z t wound to induce a number of 2P magnetic poles pj per phase when a current flows, and wherein at a front layer jump section projecting from the stator, layer jumps with a N / 2P different slot pitch only between exactly two adjacent poles p t , p2are present in one phase each.

[0011] For the following description, it is advisable to establish a uniform marking. The choice of marking does not limit the invention, and equivalent markings may also be used. For the following marking of the teeth, for example, tand grooves whose index i takes the values ​​1 , 2, ... , N, where i = i + N. Here, rtt denotes the groove which is defined by the teeth z t and z i+1 A conductor strand that is (section-wise) connected to the teeth z i+1 , e.g. i+2 , ..., z i+x wound has a slot pitch x. This means that on the one hand, part of this conductor strand is wound within the slot pitch x i+1 adjacent groove Hi and on the other hand another part of this conductor strand within the tooth z i+x adjacent groove n i+x For the designation of the poles Pj, their index j takes the values ​​1 , 2, ... , 2P, where j = j + 2P. For the designation of the conductor layers l k whose index k takes the values ​​1 , 2, ... , L, where L is the number of conductor layers. The conductor layers l kwith increasing index k the conductor layers arranged further inward in the radial direction (of the stator). In a layer jump, a conductor strand changes from a conductor layer l k into another conductor layer l k2 , where fcl = k2.

[0012] By creating layer jumps at a front layer jump section protruding from the stator with a N / 2p different slot pitch only between exactly two adjacent poles p t , p2are present in one phase each, the front layer jump section is designed to be very compact. According to an advantageous aspect, in the case of layer jumps with a N / 2p different slot pitch, the first conductor strand of each phase has a slot pitch that differs from the slot pitch of the second conductor strand of the same phase. Thus, the first conductor strand and the second conductor strand of a phase intersect at these layer jumps.

[0013] When using hairpins as conductor strands, these layer jumps, in which the first conductor strand and the second conductor strand of a phase cross, can be designed such that pin sections of the hairpins are arranged at a distance parallel to a rotation axis of the stator.

[0014] Another advantageous aspect is that layer jumps with a N / 2P different groove pitch the groove pitch is equal N / 2p + 1 or^ / 2- 1. This means that the groove pitches at these layer jumps only deviate by the distance of one groove from the groove pitch N / 2P and the winding arrangement is thus designed to be particularly symmetrical and space-saving, particularly at the front layer jump section.

[0015] According to a particularly advantageous aspect, exactly two layer jumps per conductor strand and per phase are provided on the front layer jump section with a N / 2P different slot pitches are available. By not having more than exactly two layer jumps per conductor strand with a N / 2P different slot pitches are present, the number of intersecting conductor strands is reduced as much as possible. This makes the front layer jump section particularly symmetrical and space-saving.

[0016] According to a preferred aspect, the layer jumps on the front layer jump section are provided with a N / 2p different slot pitch only between the conductor layer l L / 2 and the conductor layer l L / 2+1 where L is the number of conductor layers. Thus, the layer jumps are with a N / 2P different slot pitches are arranged centrally in the radial direction (of the stator). This means that the front layer jump section is also particularly symmetrical in this radial direction.

[0017] According to a further preferred aspect, only layer jumps with a slot pitch of N / 2P is present. This eliminates the need for conductor strands to cross at the rear layer jump section. When using hairpins as conductor strands, all hairpin pin sections can be arranged at the same height relative to the stator's rotation axis. This allows the rear layer jump section to be designed in a particularly space-saving manner.

[0018] According to a particularly preferred aspect, all layer jumps occur between two adjacent conductor layers l k and l k+1 This allows the layer jump sections to be designed particularly compactly.

[0019] According to an advantageous aspect, 2P > 4 and / or L mod 4 = 0, where L is the number of conductive trace layers.

[0020] According to a further advantageous aspect, all conductor strands are designed as flat wires. By designing all conductor strands as flat wires, it is possible to achieve a particularly high fill factor of the winding arrangement.

[0021] According to a particularly advantageous aspect, the flat wire is formed (in sections) from hairpins. Hairpins have a U-shaped geometry reminiscent of a hairpin and feature a (pointed) tapered pin section, allowing them to be placed next to each other particularly easily and in a space-saving manner. Hairpins can be used as plug-in coils and facilitate the pre-assembly of the winding arrangement before insertion into the stator.

[0022] According to a preferred aspect, all layer jumps are carried out with a N / 2p different slot pitch, a first pin section of the first conductor strand of a phase is spaced from a second pin section of the second conductor strand of the same phase parallel to a rotation axis of the stator. Since the first pin section of the first conductor strand of each phase runs below (or above) the second pin section of the second conductor strand of the same phase, the first conductor strand and the second pin section intersect at this point.

[0023] According to a further preferred aspect, all layer jumps with a groove pitch of N / 2P all© Pin sections of the conductor strands are at the same height relative to the stator's rotational axis. The pin sections can run parallel to each other, allowing the layer jump sections to be designed particularly compactly.

[0024] The invention is explained in more detail below using exemplary embodiments. In the following, the following are shown:

[0025] Fig. 1 Schematic view of a stator according to the invention with a winding arrangement;

[0026] Fig. 2 Schematic sectional view through a stator according to the invention with winding arrangement;

[0027] Fig. 3 Schematic detailed view of a part of the front layer jump section of the winding arrangement from Fig. 1 ;

[0028] Fig. 4 Winding diagram of a winding arrangement according to the invention.

[0029] Fig. 1 shows a schematic view of a stator 0 according to the invention with a winding arrangement 1. The stator 0 shown has, in particular, a distributed winding arrangement 1 and is suitable for use in an electric motor.

[0030] The winding arrangement 1 shown uses hairpins connected to conductor strands 13, 24 of three electrical phases U, V, and W. Hairpins, due to their rectangular cross-section, enable a particularly high fill factor. Furthermore, the use of hairpins facilitates the pre-assembly of the winding arrangement 1 before insertion into the stator 0.

[0031] In the shown arrangement of the winding arrangement 1 in the stator 0, the U-shaped hairpins, which open into pin sections P1, P2 parallel to the rotation axis R of the stator 0, protrude from the stator 0 at the front layer jump section vLSA and at the rear layer jump section hLSA and thus each form a winding head.

[0032] Fig. 2 shows a schematic sectional view through a stator 0 according to the invention with winding arrangement 1.

[0033] The stator 0 shown has twenty-four teeth z tand twenty-four slots rit arranged regularly along the inner circumference IU of the stator 0. Each slot Hi is defined by two adjacent teeth z i t z i+1 The index i takes the values ​​1 , 2, ... , N = 24, where i = i + N due to the periodicity.

[0034] The winding arrangement 1 shown uses hairpins that are connected to conductor strands 13, 24 (not shown). These are each arranged radially to each other within the slots spaced conductor layers on the teeth z twound to induce magnetic poles when a current flows. Within the cross-sectional areas of the conductors, the phases U, V, W and the electrical contact are indicated as U1, U2, U3, U4, V1, V2, V3, V4, W1, W2, W3, W4. Conductors marked U1, U3 form the conductor strand 13 (not shown) of phase U. Conductors marked U2, U4 form the conductor strand 24 (not shown) of phase U. Conductors marked V1, V3 form the conductor strand 13 (not shown) of phase V. Conductors marked V2, V4 form the conductor strand 24 (not shown) of phase V. Conductors marked W1, W3 form the conductor strand 13 (not shown) of phase W. Conductors marked W2, W4 form the conductor strand 24 (not shown) of phase W.

[0035] Fig. 3 shows a schematic detailed view of a part of the front layer jump section vLSA of the winding arrangement 1 from Fig. 1.

[0036] The distributed winding arrangement 1 shown, which is arranged in the stator 0, has a first conductor strand 13 and a second conductor strand 24 per electrical phase U, V, W. The winding arrangement 1 uses hairpins that are connected to the conductor strands 13, 24 and provide the three electrical phases U, V, W. The (tapered U-shaped) hairpins, which open into pin sections P, P1, P2 parallel to the rotation axis R, protrude from the stator 0 at the front layer jump section vLSA and thus form a winding head.

[0037] All conductor strands 13, 24 are arranged radially to each other within the N slots n t (not shown) spaced-apart conductor track layers l k by groove pitches spaced on the teeth z t(not shown) of the stator 0 to induce a number of 2P magnetic poles per phase U, V, W when a current flows, of which in the view shown two adjacent magnetic poles p per phase t , p2 are marked.

[0038] At the front layer jump section vLSA protruding from the stator 0, layer jumps with a N / 2p different slot pitch only between the exactly two adjacent poles p t , p2each of a phase U, V, W. There are exactly two layer jumps per conductor strand 13, 24 and per phase U, V, W with a N / 2P different groove pitches are available. This makes the front layer jump section vLSA very compact.

[0039] By not having more than exactly two layer jumps per conductor strand 13, 24 with a N / 2P different slot pitches are present, the number of intersecting conductor strands 13, 24 is reduced as much as possible. This makes the front layer jump section vLSA particularly symmetrical and space-saving.

[0040] For layer jumps with a N / 2P different slot pitch, the first conductor strand 13 of each phase U, V, W has a slot pitch of N / 2p ~ 1 au which is different from the groove pitch N / 2P + 1 of the second conductor strand 24 of the same phase U, V, W. Thus, at these layer jumps, the first conductor strand 13 and the second conductor strand 24 of a phase U, V, W cross in the area of ​​the respective pin sections P1, P2. By changing the slot pitches at these layer jumps by only the distance of one slot from the slot pitch N / 2P, the winding arrangement 1 is also designed to be particularly symmetrical and space-saving in this area. The pin sections P1, P2 are designed such that they are arranged at a distance parallel to the rotation axis R of the stator 0. Because the first pin section P1 of the first conductor strand 13 of each phase U, V, W runs under the second pin section P2 of the second conductor strand 24 of the respective same phase U, V, W, the first conductor strand 13 and the second pin section P2 cross at this point in a particularly space-saving manner. This arrangement is referred to as a pin-over-pin arrangement.

[0041] For all layer jumps with a groove pitch of N / 2p, all pin sections P of the conductor strands 13, 24 are at the same height relative to the rotational axis R of the stator 0. The pin sections P run parallel to each other. This allows the remaining part of the front layer jump section vLSA to be designed compactly.

[0042] Fig. 4 shows a winding diagram of a winding arrangement 1 according to the invention.

[0043] The distributed winding arrangement 1 shown has two conductor strands 13, 24 per electrical phase U, V, W. These are each arranged in conductor track layers l spaced radially from one another within the slots rtt k on teeth z t (not shown) wound to induce a number of 2P = 4 magnetic poles pj per electrical phase U, V, W when current flows.

[0044] In the winding diagram shown, each place where a conductor is located within a slot Hi and on a conductor layer l kcan run and are marked as U1, U2, U3, U4, V1, V2, V3, V4, W1, W2, W3, W4. Conductors running at the locations marked U1, U3 form conductor strand 13 of phase U. Conductors running at the locations marked U2, U4 form conductor strand 24 of phase U. Conductors of phase V are not shown. However, they would run correspondingly at the locations marked V1, V2, V3, V4. Conductors of phase W are also not shown. However, they would run correspondingly at the locations marked W1, W2, W3, W4.

[0045] For marking the grooves n twhose index i takes on the values ​​1, 2, ..., N, where due to the periodicity i = i + N. The course of the conductor strands 13, 24 (not shown) is shown only for phase U. Solid lines indicate the conductor strands 13, 24 of phase U at the front layer jump section, and dashed lines indicate the conductor strands 13, 24 of phase U at the rear layer jump section. The slot pitches can thus be read off by subtracting the indices i of the slots rtt between the start and end points of the lines.

[0046] For marking the conductor track layers l k whose index k takes the values ​​1 , 2, ... , L = 8, where L is the number of conductor layers. The conductor layers l k with increasing index k in the radial direction of the stator 0 (in Fig.

[0047] 2) further inside arranged conductor track layers l k. In a layer jump, a conductor strand changes from one conductor layer l k4 into another conductor layer l k2 , where

[0048] In the example shown, N = 24 and L = 8. However, the winding scheme shown can easily be adapted for winding arrangements with larger or smaller N and / or L, as well as for use with more or fewer electrical phases.

[0049] At the front layer jump section, indicated by continuous lines, the layer jumps are with a N / 2P = 6 different slot pitch only between the conductor layer l L / 2 = l4and the conductor layer l L / 2+1 = l5, i.e., centrally located in the radial direction (of the stator). Thus, the front layer jump section is particularly symmetrical with respect to this radial direction.

[0050] These layer jumps with a N / 2P = 6different slot pitch are only between the exactly two adjacent poles p t , p2each of a phase U, V, W. There are exactly two layer jumps per conductor strand 13, 24 and per phase U, V, W with a N / 2P = 6 different groove pitches available.

[0051] For layer jumps with a N / 2P = 6 different slot pitch, the first conductor strand 13 of each phase U, V, W has a slot pitch of N / 2P - 1 = 5, which is different from the groove pitch N / 2P + 1 = 7 of the second conductor strand 24 of the same phase U, V, W. Thus, at these layer jumps, in the illustration shown between the slots and n8, n2and n7, n7and n 14 , or n8and n 13, the first conductor strand 13 and the second conductor strand 24 of a phase U, V, W in the area of ​​the respective pin sections P1, P2. By changing the slot pitches at these layer jumps only by the distance of one slot from the slot pitch N / 2p = 6 The winding arrangement 1 is also designed to be particularly symmetrical and space-saving in this area.

[0052] At the rear layer jump section, indicated by dashed lines, only layer jumps with a groove pitch of N / 2P = 6 This eliminates the need for conductor strands to cross at the rear layer jump section.

[0053] Reference symbol

[0054] 0 Stator

[0055] 1 Winding arrangement

[0056] 13 first conductor strand

[0057] 24 second conductor strand z t tooth n. groove

[0058] Pj magnetic pole l k Conductor layer

[0059] N Number of grooves

[0060] L Number of conductor layers

[0061] 2P Number of magnetic poles

[0062] IU inner circumference vLSA front layer jump section hLSA rear layer jump section U (electrical) phase

[0063] V (electrical) phase

[0064] W (electrical) phase

[0065] R Rotation axis of the stator

Claims

Patent claims 1. Stator (0) with a winding arrangement (1), in particular a distributed winding arrangement (1), for an electric motor with a number of N slots n arranged regularly along an inner circumference (IU) of the stator (0) t , each of which is formed by two adjacent teeth t , e.g. i+l are limited, wherein the winding arrangement (1) comprises a first conductor strand (13) and a second conductor strand (24) per electrical phase (U, V, W), and wherein all conductor strands (13, 24) are each arranged radially relative to one another within the slots n t spaced-apart conductor track layers l k by groove pitches spaced on the teeth z t wound to form a number of 2P magnetic poles p y per phase (U, V, W), and wherein layer jumps with a N / 2P different slot pitch only between exactly two adjacent poles p t , p2are present in each phase (U, V, W).

2. Stator (0) with a winding arrangement (1) according to claim 1, wherein in the case of layer jumps with a N / 2P different slot pitch, the first conductor strand (13) of each phase (U, V, W) has a slot pitch which is different from the slot pitch of the second conductor strand (24) of the same phase (U, V, W).

3. Stator (0) with a winding arrangement (1) according to one of the preceding claims, wherein in the case of layer jumps with a slot pitch different from N / 2P, the slot pitch is equal to N / 2P + 1 °der N / 2P ~~ 1.

4. Stator (0) with a winding arrangement (1) according to one of the preceding claims, wherein at the front layer jump section (vLSA) there are exactly two layer jumps per conductor strand (13, 24) and per phase (U, V, W) with a slot pitch different from N / 2P).

5. Stator (0) with a winding arrangement (1) according to claim 4, wherein at the front layer jump section (vLSA) the layer jumps are arranged with a N / 2P different slot pitch only between the conductor layer l L / 2 and the conductor layer l L / 2+i are present, where L is the number of conductor layers.

6. Stator (0) with a winding arrangement (1) according to one of the preceding claims, wherein on a rear layer jump section (hLSA) projecting from the stator (0) only layer jumps with a slot pitch of N / 2P are present.

7. Stator (0) with a winding arrangement (1) according to one of the preceding claims, wherein all layer jumps between two adjacent conductor track layers l k and l k+1 appear.

8. Stator (0) with a winding arrangement (1) according to one of the preceding claims, wherein 2P > 4 and / or L mod 4 = 0, where L is the number of conductor track layers.

9. Stator (0) with a winding arrangement (1) according to one of the preceding claims, wherein all conductor strands (13, 24) are designed as flat wire.

10. Stator (0) with distributed winding arrangement (1) according to claim 9, wherein the flat wire is formed from hairpins.

11. Stator (0) with a winding arrangement (1) according to claim 9 or 10, wherein at all layer jumps with one of N / 2p different slot pitch, a first pin section (P1) of the first conductor strand (13) of a phase (U, V, W) is spaced from a second pin section (P2) of the second conductor strand (24) of the same phase (U, V, W) parallel to a rotation axis (R) of the stator (0).

12. Stator (0) with a winding arrangement (1) according to one of claims 9 to 11, wherein at all layer jumps with a slot pitch of N / 2P all® pin sections (P) of the conductor strands (13, 24) are at the same height with respect to a rotation axis (R) of the stator (0).

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