Stator segment, electric machine and wind turbine

Abstract

Described is a stator segment (101a, b, c) for an electric machine (100), in particular a permanent magnet synchronous generator, comprising: a core ring portion (106a, b, c) extending in a circumferential direction (cd) forming a smaller than a complete circumference; a plurality of first teeth (107a, b, c) extending radially from the ring portion (106a, b, c); two second teeth (108a, b, c) extending radially from the ring portion (106a, b, c) and arranged at both circumferential ends of the ring portion; wherein a first slot (109a, b, c) is formed between every two adjacent first teeth (107a, b, c), and wherein a second slot (110a, b, c) is formed between each second tooth (108a, b, c) and the adjacent first tooth (107a, b, c), the stator segment further comprising: a set of multi-phase windings (105A, B, C) wound according to a concentrated winding topology.

Description

Technical Field

[0001] The present invention relates to a stator segment for an electric motor, to an electric motor comprising a plurality of stator segments, and further to a wind turbine comprising a generator. Background Technology

[0002] Conventionally, a stator can be assembled from multiple stator segments, each spanning a portion of a complete circumference. Conventionally, stator segments have exposed end coils, i.e., coils exposed to air at the circumferential ends of the segment rather than enclosed in slots.

[0003] During transport, assembly, and operation, exposed end coils are subjected to unreliable mechanical forces. A critical consequence is that the two facing end coils of two adjacent sections may scrape against each other under electromagnetic forces, thermal deformation, and vibration. Without reliable securing, this can cause insulation damage, necessitating generator replacement.

[0004] A common, straightforward solution is to increase the gap between segments to prevent contact or contact between adjacent segments. However, this may increase 2f torque harmonics, and more importantly, it does not eliminate the risk of damage due to scraping between the two end coils from adjacent segments. For securing exposed end coils, mechanical fixing solutions (such as using straps, clamps, bolts, etc.) may not be the optimal solution in terms of improving lifespan and reliability.

[0005] Another common approach is to remove the end coils, leaving the first and last slots of each segment without coils; however, this significantly reduces output power and increases unwanted harmonics. Furthermore, a single-layer concentrated winding topology has been conventionally employed, which does not have exposed end coils and can be easily modularized or segmented. Disadvantages include higher harmonics, lower torque, and therefore reduced efficiency.

[0006] Therefore, there may be a demand for a stator segment for an electric motor, a demand for an electric motor, and a demand for a wind turbine, in which the disadvantages briefly described above are reduced or even avoided. Summary of the Invention

[0007] This need can be met by the subject matter according to the independent claims. Advantageous embodiments of the invention are described by the dependent claims.

[0008] According to an embodiment of the present invention, a stator segment for an electric motor, particularly a permanent magnet synchronous generator, is provided, the stator segment comprising: a core ring portion extending in a circumferential direction to form a circle smaller than a complete circumference; a plurality of first teeth extending radially from the ring portion; two second teeth extending radially from the ring portion and disposed at two circumferential ends of the ring portion; wherein a first slot is formed between every two adjacent first teeth, and a second slot is formed between each second tooth and an adjacent first tooth, the stator segment further comprising: a multiphase winding set wound according to a concentrated winding topology.

[0009] The stator section can be made of a ferromagnetic material (layer) with high magnetic permeability. The diameter of the assembled stator can be between 5 m and 15 m. The generator can be a wind turbine generator driven by a rotating shaft, with multiple rotor blades mounted on the rotating shaft.

[0010] The core ring portion can be a section or segment of a ring, and particularly a segment of a circular ring. According to different embodiments, the core ring portion can span an angular range of less than or equal to 180°. Therefore, the entire stator can be assembled from two, three, four, five, six, ..., eighteen or more stator segments.

[0011] Each stator segment may have its own (separate) associated winding set, particularly a multiphase winding set. The core ring portion and the first and / or second teeth may be integrally formed, particularly formed in a layer of magnetic permeable material. The first and / or second teeth may extend radially inward or outward from the core ring portion.

[0012] The two second (half) teeth can limit the stator segment at the two circumferential ends. Therefore, the two second teeth can protect any conductor portion that can be placed in the second slot. As a result, the protection of the conductor portion from damage can be improved.

[0013] Any first groove is formed between two adjacent first teeth on two circumferences. Any second groove is formed or limited by the first teeth on one circumferential side and by the second teeth on the other circumferential side. The width of the first groove may be substantially equal to the width of the second groove, or may have different dimensions depending on the application.

[0014] The first tooth and the second (half) tooth can be constructed in a similar manner, but the second (half) tooth can have a smaller circumferential width than the first tooth. In the assembled stator, a second tooth of the first stator segment can be close to or even contact the second tooth of the second segment. A small gap can be provided between adjacent stator segments to avoid direct or immediate contact between the corresponding second teeth. Two adjacent stator segments can be mounted or connected to each other, for example, by bolts. Alternatively or additionally, other mounting or connection methods are possible.

[0015] The second half-tooth can also be called an "end half-tooth" because it is located at the circumferential end of the corresponding stator segment and typically has a circumferential width significantly smaller than that of the first tooth. The auxiliary end half-tooth, or generally the second tooth, at the circumferential end of each segment can enclose the end coil in a (second) slot. In motors assembled from multiple stator segments, two second half-tooths from different adjacent stator segments are placed close together or even in contact with each other to form a (single) second full tooth.

[0016] In a concentrated winding topology, all turns (wound around a single tooth) can have the same magnetic axis. According to the concentrated winding topology, the resulting coil is concentric, specifically concentric with respect to the first tooth.

[0017] The number of phases can be, for example, two, three, four, five, six, seven, or even more. For example, for a three-phase system, the winding bundle may include three conductors, which can be connected in a star or delta configuration. Preferably, in a segmented stator design, the star connection has three phases connected to the center neutral point of the stator segment. The neutral points of different stator segments are connected to each other via electrical connections (e.g., busbars).

[0018] Thanks to the second tooth that protects the end coils from damage, the stator segment can be transported and assembled with reduced risk of damaging the end coils.

[0019] According to an embodiment of the invention, the multiphase winding assembly includes conductors for each phase, wherein each conductor is wound, in particular, one or more turns around at least one of the first teeth to form at least one coil, such that there are two half-coils in each of the first slots.

[0020] Each wire can be wound several turns around at least one of the first teeth, and more particularly around several of the first teeth, to form a coil at each first tooth around which the wire is wound. Therefore, in each of the first slots, there can be a half-coil wound around an adjacent first tooth and another half-coil wound around another adjacent first tooth. Thus, a double-layer structure can be formed. In each of the second slots, there can be only one half-coil, so that there is no double-layer structure in each of the second slots.

[0021] According to an embodiment of the invention, the two half-coils in each of the first slots are formed by portions of two wires associated with one or by portions of two different wires associated with each other.

[0022] Therefore, it can provide great flexibility for the windings.

[0023] According to an embodiment of the invention, in each of the first slots, a double-layer design of the conductor portion is provided, wherein the conductor portions belonging to different half-coils in any one of the first slots are arranged circumferentially and / or radially adjacent to each other.

[0024] In each of the second slots, there is no double-layer design for the conductor portion. In each of the second slots, there is only one half-coil of a coil wound around the adjacent first tooth.

[0025] According to an embodiment of the invention, multiple wires are wound around the first tooth but not around the second tooth to form a coil, such that in each of the first slots, there are two half-coils.

[0026] According to an embodiment of the invention, none of the conductors in the winding set are wound around any of the second teeth. Therefore, none of the second teeth has or lacks any coil. Furthermore, in the assembled state of the entire stator, no coil is wound around two adjacent second teeth.

[0027] According to an embodiment of the invention, each of the second teeth has a circumferential range that is less than, greater than, or equal to the circumferential range of any of the first teeth, and / or wherein each of the second teeth has a radial range that is substantially equal to the radial range of any of the first teeth.

[0028] The circumference of the second tooth can, for example, be between 10% and 70% of the circumference of the first tooth. Therefore, weight can be reduced.

[0029] According to an embodiment of the invention, a plurality of first teeth and second teeth extend radially outward from the ring portion, and / or wherein the ring portion spans between 180° and 5° of a circumference of 180°, 120°, 90°, 72°, 60°, 45°, 40°, 36°, 30°, 24°, 22.5°, 20°, 18°, 15°, 12°, 10°, or 360°.

[0030] Therefore, it provides great flexibility, enabling it to meet the requirements of transportation equipment and opportunities.

[0031] According to embodiments of the present invention, an electric motor, particularly a permanent magnet synchronous generator, is provided, comprising: a plurality of stator segments according to one of the foregoing embodiments, assembled to form a complete circumference; a rotor, particularly an outer rotor, rotatably mounted relative to the stator and having a plurality of permanent magnets mounted at different circumferential positions to form a plurality of magnetic poles; the plurality of stator segments having winding sets with a concentrated winding topology. The winding sets are electrically connected such that the winding sets of adjacent stator segments are phase-shifted relative to each other, wherein there are at least three sets of stator segments, wherein all winding sets of a set of stator segments are not phase-shifted relative to each other, and wherein the winding sets of different sets of stator segments are phase-shifted relative to each other.

[0032] Multiple stator segments can be mounted onto each other, so that the assembled and mounted stator segments form a ring spanning a complete circumference. Therefore, the corresponding second (half) teeth of the stator segments can contact each other, or can be very close to each other, with a small gap between them. Two adjacent second half teeth form a full tooth, also known as a second full tooth.

[0033] The rotor can be an inner rotor or an outer rotor. Preferably, the first and second teeth extend radially outward, and the rotor is an outer rotor. The winding sets located in different stator segments can be physically equal, identical, or indistinguishable, but can provide different electrical phase sequences. The corresponding winding sets in different stator segments are not electrically connected to each other, but can be connected to their respective associated transducers.

[0034] 2 * ∆Qs is the total number of the second teeth, ∆Qs is the total number of the second full teeth, and Nseq is the number of stator segments, where ∆Qs = Nseq.

[0035] When the above relationship is satisfied, it is ensured that each stator segment includes a second tooth at each circumferential end for protecting the coil.

[0036] According to an embodiment of the present invention, the number of different winding schemes in a plurality of stator segments is equal to the number of phases or a multiple thereof, wherein the number of phases is particularly three.

[0037] One advantage is that each phase has the same number of coils located in the second slot (i.e., end coils), thus obtaining a balanced or symmetrical multiphase system.

[0038] According to an embodiment of the present invention, the number of first teeth Qs plus the number of second full teeth ∆Qs is the total number of teeth of the stator, wherein 2 * p + 2 * ∆p is the total number of poles in the motor. Where p is the number of pole pairs. Where ∆p is the number of additional pole pairs, Among them, Qs and 2p have a common divider. Where Qs / (2 * p) is 1.2, p is an integer. ∆p is an integer, especially an even number greater than 1.

[0039] ∆p can be, for example, 2, 4, or 6. ∆p can be an odd number, such as 3 or 5. Therefore, greater flexibility is provided.

[0040] In particular, the number of segments (equal to ∆Qs) can be equal to or greater than 12 and / or equal to or less than 18.

[0041] According to an embodiment of the invention, τp is the circumferential width or pole pitch of each of the poles, τs is the circumferential width or slot pitch of each of the first slots, tau_p / tau_s (Qs, ps) = tau_p / tau_s (Qs+Delta_Qs, ps+Delta_P) = τp / τs = Qs / (2p), w_EHT is the width of the second tooth, where τs depends on ∆Qs, w_EHT and Qs, and τp depends on p and ∆p. According to an embodiment of the present invention, the motor is characterized as follows: Qs=216 and ∆Qs=12 and 2p=180 and 2*∆p = 4, and specifically has three sets of stator segments, or Qs=216 and ∆Qs=18 and 2p=180 and 2*∆p = 12, and specifically has three sets of stator segments, or Qs=288 and ∆Qs=12 and 2p=240 and 2*∆p = 8, and specifically has three sets of stator segments, or Qs=288 and ∆Qs=12 and 2p=240 and 2*∆p = 4, and specifically has six sets of stator segments, or Qs=288 and ∆Qs=16 and 2p=240 and 2*∆p = 8, and specifically has four sets of stator segments, or Qs=324 and ∆Qs=18 and 2p=270 and 2*∆p = 6, and specifically has three sets of stator segments, or Qs=336 and ∆Qs=14 and 2p=280 and 2*∆p = 4, and specifically has seven sets of stator segments, or Qs=360 and ∆Qs=12 and 2p=300 and 2*∆p = 4, and specifically has three sets of stator segments, or Qs=360 and ∆Qs=15 and 2p=300 and 2*∆p = 6, and specifically has five sets of stator segments, or Qs=360 and ∆Qs=15 and 2p=300 and 2*∆p = 10, and specifically has three sets of stator segments, or Qs=384 and ∆Qs=16 and 2p=320 and 2*∆p = 8, and specifically has four sets of stator segments, or Qs=432 and ∆Qs=12 and 2p=360 and 2*∆p = 4, and specifically has six sets of stator segments, or Qs=432 and ∆Qs=12 and 2p=360 and 2*∆p = 8, and specifically has three sets of stator segments, or Qs=432 and ∆Qs=18 and 2p=360 and 2*∆p = 12, and in particular, it has three sets of stator segments.

[0042] According to an embodiment of the invention, a set of stator segments is connected to one or two converters. Therefore, different power capacities can be provided.

[0043] According to an embodiment of the present invention, a wind turbine is provided, comprising: a rotating shaft, wherein a plurality of rotor blades are mounted on the rotating shaft; and a motor according to any of the foregoing embodiments, wherein the rotor of the motor is mechanically, in particular directly coupled to the rotating shaft, for example having a 1:1 transmission ratio (e.g., without a gearbox).

[0044] The aspects of the invention defined above and others will become apparent from the examples of embodiments described below, and will be explained with reference to the examples of embodiments. The invention will be described in more detail below with reference to examples of embodiments, but the invention is not limited thereto. Attached Figure Description

[0045] Embodiments of the invention will now be described with reference to the accompanying drawings. The invention is not limited to the illustrated or described embodiments.

[0046] Figure 1 A schematic diagram illustrates an electric motor according to an embodiment of the present invention, which includes a plurality of stator segments according to an embodiment of the present invention; Figure 2 A stator segment according to another embodiment of the present invention is schematically illustrated; Figure 3 The illustration schematically depicts multiple assembled stator segments according to embodiments of the present invention; and Figure 4 A wind turbine according to an embodiment of the present invention is schematically illustrated. Detailed Implementation

[0047] The illustrations in the accompanying drawings are schematic. Note that in different drawings, elements that are similar or identical in structure and / or function are provided with the same reference numerals or reference numerals that differ only in the first digit. Description of an element not described in one embodiment may be obtained from the description of that element with respect to another embodiment.

[0048] According to an embodiment of the invention, the circumferential end coil side of the stator segment is closed by merging two tooth / pole combinations (adding an additional slot / pole to the original slot / pole combination). Therefore, an auxiliary end segment half-tooth can be added with minimal impact on performance (i.e., torque), and with the advantages of lower cogging torque and torque ripple. This dimension can be designed to eliminate the effects of inter-segment gaps.

[0049] Figure 1 The schematically illustrated motor 100 includes multiple stator segments 101a, 101b, 101c, which are assembled to form a complete circumference (in the circumferential direction cd) and form a stator 103. The motor 100 also includes a rotor 102 rotatably mounted relative to the stator 103 (formed by the assembled stator segments 101a, 101b, 101c). The rotor 102 has multiple magnets 104, 105 mounted thereon, wherein each pair of magnets 104, 105 forms a pole pair with alternating poles or a magnetic pole configuration, such that magnet 104 provides a north pole, for example, at a radially inner end, and magnet 105 provides a south pole at a radially inner end.

[0050] In the motor 100, each of the multiple stator segments 101a, 101b, 101c has winding sets 105A, 105B, 105C for three different electrical phases A, B, C. Figure 1 In this context, the winding topology of a three-phase conductor is indicated by including an indication of the winding direction (sense), meaning whether it extends inward or outward.

[0051] In the illustrated embodiment, the motor 100 includes three stator segments 101a, 101b, and 101c, with an inter-segment gap 120 between adjacent segments. In other embodiments, more or fewer segments may be provided to form a complete circumference of the stator.

[0052] Each stator segment 101a, 101b, 101c includes a core ring portion 106a, 106b, 106c extending in the circumferential direction cd, forming a smaller than a complete circumference. In the illustrated embodiment, each stator segment forms a 120° segment of a 360° circumference. Each stator segment includes a plurality of first teeth 107a, 107b, 107c extending radially (outward) from the corresponding ring portion 106a, 106b, 106c. Each of the stator segments 101a, 101b, 101c also includes two second (half) teeth 108a, 108b, 108c, which also extend radially (outward) from the ring portion 106a, 106b, 106c and are arranged at the two circumferential ends of the corresponding ring portion or stator segment 101a, 101b, 101c.

[0053] Thus, a first groove 109a is formed between every two adjacent first teeth (e.g., tooth 107a). Similarly, a first groove 109b is formed between any two first teeth 107b in the second stator segment 101b. This also applies to the third segment 101c. Furthermore, a second groove 110a is formed between each second (half) tooth 108a and an adjacent first tooth 107a.

[0054] Multiphase winding sets 105A, 105B, and 105C are wound across the assembled stator according to a concentrated winding topology. The multiphase winding sets include conductors (electrical conductors) for each phase (e.g., A, B, C), which will be wound around several teeth. For example, for phase A, conductor 105A is provided. This conductor 105A is wound around at least one of the first teeth 107a to form at least one coil, such as a coil formed by winding conductor 105A. Figure 1 The coil 111A is shown. Therefore, in each of the first slots 109a, there are two half-coils (belonging to the same or different phases).

[0055] In each of the first slots 109a, the two half-coils are formed by portions of two wires associated with one phase, or portions of two wires associated with two different phases, or portions of two wires associated with one system, or portions of two wires associated with two different systems. For example, in the first slot labeled 109a', portions of wires belonging to phase A are provided. In contrast, in the first slot 109a", one half-coil belongs to phase A and the other half-coil belongs to phase C.

[0056] In each of the first slots 109a, b, and c, a double-layer design of the conductor portions is provided, wherein the conductor portions belonging to different half-coils are arranged circumferentially and / or radially adjacent to each other. In the illustrated embodiment, the conductor portions in one of the first slots 109a, b, and c are arranged circumferentially adjacent (side by side). In other embodiments, the different half-coils may be arranged radially adjacent to each other (also referred to as arranged one above the other).

[0057] As from Figure 1 Understandably, none of the wires 105A, 105B, and 105C are wrapped around any of the second teeth 108a, b, and c.

[0058] As from Figure 1 It can also be understood that each of the second (half) teeth 108a, b, c has a circumferential range c2 smaller than the circumferential range c1 of the first teeth 107a, b, c. The radial ranges of the second and first teeth can be substantially similar or identical. In other embodiments, the corresponding stator segments can span angular ranges different from those illustrated.

[0059] In the illustrated embodiment, the total number of the second (half) teeth 108a, b, c is 6, and the number of segments is 3. Therefore, the equation ∆Qs = Nseq holds, where 2 × ∆Qs is the total number of the second (half) teeth 108a, b, c, and Nseq is the number of stator segments. ∆Qs is the total number of the second full teeth of the motor, each second full tooth being formed by two adjacent second half teeth.

[0060] As can be seen from the different shading for different phases in different extension directions, the windings in different segments do not follow the same topology, but rather have phase shifts relative to each other. It should be understood that each of stator segments 101a, b, and c includes its own set of multiphase windings. Figure 1 Only one winding set is marked in the text, namely winding set 105A, B, C.

[0061] A concentrated winding generator according to an embodiment of the present invention is characterized by a tooth / pole (or slot / pole) combination, i.e., the ratio Qs / 2p (where Qs is the number of teeth or slots, and 2p is the number of poles (2p is also written as 2*p, where p is the number of pole pairs)). This is typically described by the minimum number of teeth / pole (or slot / pole) combinations in the modular generator if Qs / 2p has a common divisor. For example, for Qs=144 and 2p=120, the tooth / pole (or slot / pole) combination is 12 / 10. For a concentrated winding generator, this combination is typically close to 1. According to embodiments of the present invention, the following combinations of Qs / 2p are possible, or can serve as a starting point for embodiments of the invention: 12 / 10, 12 / 14, 24 / 22, 18 / 14, 18 / 16, 18 / 20, 18 / 22, 24 / 20, 24 / 26, 27 / 22, 27 / 24, 27 / 26, 30 / 26, etc. Typically, the relationship Qs / 2p is in the range of 0.86 to 1.29, preferably 1.2.

[0062] For large generators, despite the large number of slots and poles, the combination may still be the same as that of small generators.

[0063] An example of the slot / pole number (not limited to this invention) could be 18, multiplied by a 12 / 10 slot / pole combination, giving 216 slots (Qs=216) and 180 poles (2p=180) as a reference motor. The slot / pole relationship is 1.2. This motor can be divided into 12 segments (∆Qs=12). According to an embodiment of the invention, for each segment, additional half teeth are added at the two circumferential ends, i.e., 24 half teeth are added (or 12 full teeth are added), resulting in Qs=12. To maintain the harmonic behavior of this motor in terms of torque fluctuation (which is similar to the reference motor), several poles must be added to the number of poles of the reference motor. In this case, the rotor adds 2 or 4 poles. Therefore, this can give a total slot / pole number of 228 / 182 or 228 / 184.

[0064] For large generators with a conventional double-layer concentrated winding design, the circumferential end coil side of each stator segment is exposed to air. According to embodiments of the invention, it is proposed to enclose the circumferential end coil side in slots by adding additional “end half-tooths” (also referred to as “second (half) teeth”) at each circumferential end of the segment, and simultaneously (optionally) having one or more additional poles. The number of added “half-tooths” can be limited to 2 × ∆Qs. The number of added poles is limited to 2 × ∆p. They are determined based on the original combination of Qs / 2p. The width of the added end half-tooths and the winding scheme should also be tuned for good performance.

[0065] 1) The number of teeth added The number of added half-teeth is limited to 2 × ∆Qs. The two facing end half-teeth of two adjacent segments are considered as a "full" tooth here. Therefore, ∆Qs is the number of added "full" teeth, which should be the same as the number of segments Nseg, meaning ∆Qs = Nseg.

[0066] 2) The number of poles added The number of poles added is limited to 2 × ∆p, where ∆p is the number of pole pairs added. Theoretically, ∆p is an independent variable that can take any integer value. However, it affects the determination of the end-tooth half-width, and therefore the constraints given below can be applied.

[0067] 3) The increased width of the end half tooth To allow sufficient space for the added end half-tooth, the width of the other "normal" slots (i.e., the first slot) and / or teeth (i.e., the first tooth) must be reduced, which means the slot pitch τs decreases. The new τs depends on the number of added full teeth ∆Qs and the width w_EHT of the added end half-tooth. Simultaneously, the pole pitch τp also decreases due to the added poles.

[0068] τs = τs(Qs, ∆Qs, w_EHT) τp = τp(p, ∆p).

[0069] For the purpose of low harmonics, the width of the increased end half tooth should ensure that the new combination of τp / τs is the same as or close to the original combination of slot and pole number Qs / 2p.

[0070] Therefore, the following equation(s) hold true: τp / τs = Qs / 2p or τp / τs is approximately equal to Qs / 2p 4) Winding scheme After adding a new slot / pole combination (i.e., additional teeth and poles), the winding scheme must be adjusted. The new winding scheme depends on the phase shift Θ (i.e., electrical angle) between the coils at the two adjacent ends of two adjacent sections under no-load conditions, which should satisfy... Θ = 180 * (2p / Qs + 2∆p / ∆Qs) or Θ is approximately equal to: 180 * (2p / Qs + 2∆p / ∆Qs) Different ∆p / ∆Qs can lead to different winding schemes in each segment, resulting in different segment types. For the purpose of balancing an m-phase system, the number of different segment types (or winding schemes) is recommended to be m or a multiple of m, where the number of end coils in each phase is the same. The final determination of the end half-tooth width and the number of poles added depends on performance requirements (e.g., output power, torque ripple, losses, etc.) and manufacturing complexity.

[0071] Compared to the original design, the proposed design method will have a smaller impact on performance (i.e. torque) based on the correct selection of ∆p, ∆Qs, and wEHT.

[0072] The original design can refer to any generator design that has the same total number of slots (or teeth) as the total number of first teeth in all segments, and the same or approximately the same tooth / pole (or slot / pole) combination Qs / 2p as τp / τs, such as, but not limited to, 12 / 10, 12 / 14, 24 / 22, 18 / 14, 18 / 16, 18 / 20, 18 / 22, 24 / 20, 24 / 26, 27 / 22, 27 / 24, 27 / 26, 30 / 26, etc. (τp and τs are the pole pitch and slot pitch of the first slot of the generator with end teeth design).

[0073] In this way, technicians can find the original design (Qs and 2p) by measuring τp and τs of an existing design with end half-tooths.

[0074] It also has the advantages of lower cogging torque and torque ripple, while eliminating the effects of inter-segment backlash.

[0075] A conventional generator design with 36 slots / 30 poles and 3 sections can be considered. Starting from this conventional generator, according to an embodiment of the invention, three teeth (2×∆Qs = 6) and two additional poles (2×∆p = 2) are added. The stator winding scheme must also be modified to ensure maximum output power.

[0076] Each segment will have a different winding scheme. See Table 1 below. Figure 1 The winding scheme of the motor shown is given according to the exemplary proposed design (based on a 36-slot / 30-pole design with end half-tooth, 30 poles + 2 additional poles).

[0077] Table 1: Section 1 -B, +B, +B, -B, +C, -C, -C, +C, -A, +A, +A, -A, +B, -B, -B, +B, -C, +C, +C, -C, +A, -A, -A, +A Section 2 -C, +C, +C, -C, +A, -A, -A, +A, -B, +B, +B, -B, +C, -C, -C, +C, -A, +A, +A, -A, +B, -B, -B, +B Section 3 -A, +A, +A, -A, +B, -B, -B, +B, -C, +C, +C, -C, +A, -A, -A, +A, -B, +B, +B, -B, +C, -C, -C, +C

[0078] The new winding scheme is determined by the phase shift angle Θ, which is 270° (electrical angle in the illustrated embodiment). As can be understood from Table 1, corresponding to... Figure 1 The winding schemes in segments 1, 2, and 3 of segments 101a, 101b, and 101c shown are mutually shifted (and reversed), but not equal.

[0079] For any given number of phases and a given slot / pole combination, following the equations regarding winding schemes, a technician will generate a corresponding winding scheme with phase shifts.

[0080] According to other embodiments of the present invention, the motor may be characterized as follows: Qs=216 and ∆Qs=12 and 2p=180 and 2*∆p = 4, and specifically has three sets of stator segments, or Qs=216 and ∆Qs=18 and 2p=180 and 2*∆p = 12, and specifically has three sets of stator segments, or Qs=288 and ∆Qs=12 and 2p=240 and 2*∆p = 8, and specifically has three sets of stator segments, or Qs=288 and ∆Qs=12 and 2p=240 and 2*∆p = 4, and specifically has six sets of stator segments, or Qs=288 and ∆Qs=16 and 2p=240 and 2*∆p = 8, and specifically has four sets of stator segments, or Qs=324 and ∆Qs=18 and 2p=270 and 2*∆p = 6, and specifically has three sets of stator segments, or Qs=336 and ∆Qs=14 and 2p=280 and 2*∆p = 4, and specifically has seven sets of stator segments, or Qs=360 and ∆Qs=12 and 2p=300 and 2*∆p = 4, and specifically has three sets of stator segments, or Qs=360 and ∆Qs=15 and 2p=300 and 2*∆p = 6, and specifically has five sets of stator segments, or Qs=360 and ∆Qs=15 and 2p=300 and 2*∆p = 10, and specifically has three sets of stator segments, or Qs=384 and ∆Qs=16 and 2p=320 and 2*∆p = 8, and specifically has four sets of stator segments, or Qs=432 and ∆Qs=12 and 2p=360 and 2*∆p = 4, and specifically has six sets of stator segments, or Qs=432 and ∆Qs=12 and 2p=360 and 2*∆p = 8, and specifically has three sets of stator segments, or Qs=432 and ∆Qs=18 and 2p=360 and 2*∆p = 12, and in particular, it has three sets of stator segments.

[0081] Figure 2 A stator segment 201a according to another embodiment of the invention is schematically illustrated. To form a complete circumference of the stator, 12 segments with the same geometry as stator segment 201a are required. Furthermore, stator segment 201a has second teeth 208 at the circumferential ends and first teeth 207 therebetween. In each of the first slots 209, there is a double-layer design, while in the second slot 210, there is only a single-layer design, meaning that only one half-coil exists.

[0082] Table 2 below shows the winding schemes for different segments 1 to 12 (201a, b, c, ...), one of which is... Figure 2 The diagram shows how to assemble the entire stator 203, as shown in the image. Figure 3 The illustration is schematic.

[0083] Based on a 216-slot / 180-pole design (i.e., Qs=216, 2p=180), this design has 24 end half-tooth (i.e., ∆Qs=12), 180 poles (i.e., 2p=180) + 4 additional poles (i.e., 2 * ∆p = 4). There are three sets of stator segments.

[0084] Table 2: Sections 1, 4, 7, 10 -B, +B, +B, -B, +C, -C, -C, +C, -A, +A, +A, -A, +B, -B, -B, +B, -C, +C, +C, -C, +A, -A, -A, +A, -B, +B, +B, -B, +C, -C, -C, +C, -A, +A, +A, -A Sections 2, 5, 8, 11 -A, +A, +A, -A, +B, -B, -B, +B, -C, +C, +C, -C, +A, -A, -A, +A, -B, +B, +B, -B, +C, -C, -C, +C, -A, +A, +A, -A, +B, -B, -B, +B, -C, +C, +C, -C Sections 3, 6, 9, 12 -C, +C, +C, -C, +A, -A, -A, +A, -B, +B, +B, -B, +C, -C, -C, +C, -A, +A, +A, -A, +B, -B, -B, +B, -C, +C, +C, -C, +A, -A, -A, +A, -B, +B, +B, -B

[0085] exist Figure 3 The motor shown has a total of 184 poles and 228 slots.

[0086] Advantages of embodiments of the present invention may include enabling life-reliable solutions for realizing concentrated winding topologies with modular stators and direct-drive wind turbines. Furthermore, as part of the design, 2f oscillations due to inter-segment tolerance clearances can be reduced.

[0087] Compared to exposed end coils with mechanical fixing solutions (using straps, clamps, bolts, etc.), enclosing the end coil and slot using end half-tooths is advantageous in terms of manufacturing difficulty, reliability, and lifespan. It avoids potential installation damage to the end coil due to mechanical contact. Compared to other solutions, the proposed design exhibits lower harmonics and a less significant impact on performance.

[0088] Figure 4 A wind turbine 450 according to an embodiment of the present invention is schematically illustrated. The wind turbine 450 includes a wind turbine tower 451, and a nacelle 452 is rotatably mounted on top of the wind turbine tower 451. The nacelle 452 houses a motor 400 according to an embodiment of the present invention. A rotating shaft 453 is (directly) coupled to the motor 400, and a plurality of rotor blades 454 are mounted to the rotating shaft 453. The motor outputs three-phase output power, which is provided to an (optional) converter 455. The converter converts the AC power current into a fixed-frequency AC power current and supplies the fixed-frequency power current to a wind turbine transformer 456. The motor 400 includes an outer rotor 402 that rotates relative to a stator 403, which may be similar to... Figure 1 The stator 103 shown is constructed.

[0089] Single-stage or multi-stage gearboxes can also exist in wind turbine drive systems.

[0090] It should be noted that the term "comprising" does not exclude other elements or steps, and "a" or "an" does not exclude multiple. Elements described in association with different embodiments may also be combined. It should also be noted that reference numerals in the claims should not be construed as limiting the scope of the claims.

Claims

1. Stator sections (101a, b, c) for electric motors (100), particularly permanent magnet synchronous generators, including: The core ring portion (106a, b, c) extends in the circumferential direction (cd) to form a circle smaller than the complete circumference; Multiple first teeth (107a, b, c) extend radially from the ring portion (106a, b, c); Two second teeth (108a, b, c) extend radially from the ring portion (106a, b, c) and are arranged at the two circumferential ends of the ring portion; Specifically, a first groove (109a, b, c) is formed between every two adjacent first teeth (107a, b, c). Specifically, a second groove (110a, b, c) is formed between each second tooth (108a, b, c) and the adjacent first tooth (107a, b, c). The stator segment also includes: The multiphase winding set (105A, B, C) is wound according to the concentrated winding topology.

2. The stator segment according to the preceding claim, in, The multiphase winding set (105A, B, C) includes conductors (105A) for each phase. Each wire is wound around at least one of the first teeth (107a), particularly one or more turns, to form at least one coil (111A), such that there are two half-coils in each of the first slots (109a', 109a").

3. The stator segment according to the preceding claim, in, The two half-coils in each of the first slots (109a', 109a") are formed by portions of two wires associated with one phase (A, B, C) or by portions of two wires associated with two different phases (A, B, C).

4. The stator segment according to any one of the preceding claims, wherein, In each of the first slots (109a, b, c), a double-layer design of the conductor portion is provided, wherein the conductor portions of different half-coils belonging to any one of the first slots are arranged circumferentially and / or radially adjacent to each other.

5. The stator segment according to any one of the preceding claims, wherein, None of the wires (105A, B, C) in the winding set are wound around any of the second teeth (108a, b, c).

6. The stator segment according to any one of the preceding claims, in, Each of the second teeth (108a, b, c) has a circumferential range that is less than, greater than, or equal to the circumferential range of any one of the first teeth (107a, b, c), and / or Each of the second teeth (108a, b, c) has a radial range that is substantially equal to the radial range of any one of the first teeth (107a, b, c).

7. The stator segment according to any one of the preceding claims, in, The plurality of first teeth (107a, b, c) and second teeth (108a, b, c) extend radially outward from the ring portion, and / or The ring portion spans between 180° and 5° of a circumference of 180°, 120°, 90°, 72°, 60°, 45°, 40°, 36°, 30°, 24°, 22.5°, 20°, 18°, 15°, 12°, 10°, or 360° in the circumferential direction.

8. Electric motors (100), especially permanent magnet synchronous generators, including: Multiple stator segments (101a, b, c) according to any one of the preceding claims are assembled to form a complete circumference. The rotor (102), particularly the outer rotor, is rotatably mounted relative to the stator (103) and has multiple permanent magnets (104, 105) mounted at different circumferential positions, forming multiple magnetic poles. The multiple stator segments (101a, b, c) have a winding set with a concentrated winding topology. The winding sets are electrically connected such that the winding sets of adjacent stator segments are phase-shifted relative to each other. in, There are at least three sets of stator segments. In this case, all winding sets of a set of stator segments have no phase shift relative to each other. In this context, the winding sets of different groups of stator segments are phase-shifted relative to each other.

9. The motor according to the preceding claim, in, 2 * ∆Qs is the total number of the second half teeth. Where ∆Qs is the total number of second full teeth, that is, each second full tooth is composed of two second half teeth, and Nseq is the number of stator segments, where ∆Qs = Nseq.

10. The motor according to any one of claims 8 or 9, wherein, The number of different winding schemes in the plurality of stator segments (101a, b, c) is equal to the number of phases or a multiple thereof, wherein the number of phases is particularly three.

11. The motor according to any one of claims 8 to 10, wherein, The number of first teeth Qs plus the number of second full teeth ∆Qs is the total number of teeth in the stator, where, 2 * p + 2 * ∆p is the total number of poles in the motor. Where p is the number of pole pairs. Where ∆p is the number of pole pairs added. Among them, Qs and 2p have a common divisor. Where Qs / (2 * p) is 1.2, p is an integer. ∆p is an integer, especially an even number greater than 1.

12. The motor according to any one of claims 8 to 11, wherein, τp is the circumferential width or pole distance of each of the poles. τs is the circumferential width or slot spacing of each of the first slots. tau_p / tau_s (Qs, ps) = tau_p / tau_s (Qs+Delta_Qs, ps+Delta_P)= τp / τs = Qs / (2p), w_EHT is the width of the second tooth. Where τs depends on ∆Qs, w_EHT, and Qs, Where τp depends on p and ∆p.

13. The motor according to any one of claims 8 to 12, wherein, The motor has the following characteristics: Qs=216 and ∆Qs=12 and 2p=180 and 2*∆p = 4, and has three sets of stator segments, or Qs=216 and ∆Qs=18 and 2p=180 and 2*∆p = 12, and has three sets of stator segments, or Qs=288 and ∆Qs=12 and 2p=240 and 2*∆p = 8, and has three sets of stator segments, or Qs=288 and ∆Qs=12 and 2p=240 and 2*∆p = 4, and has six sets of stator segments, or Qs=288 and ∆Qs=16 and 2p=240 and 2*∆p = 8, and has four sets of stator segments, or Qs=324 and ∆Qs=18 and 2p=270 and 2*∆p = 6, and has three sets of stator segments, or Qs=336 and ∆Qs=14 and 2p=280 and 2*∆p = 4, and has seven sets of stator segments, or Qs=360 and ∆Qs=12 and 2p=300 and 2*∆p = 4, and has three sets of stator segments, or Qs=360 and ∆Qs=15 and 2p=300 and 2*∆p = 6, and has five sets of stator segments, or Qs=360 and ∆Qs=15 and 2p=300 and 2*∆p = 10, and has three sets of stator segments, or Qs=384 and ∆Qs=16 and 2p=320 and 2*∆p = 8, and has four sets of stator segments, or Qs=432 and ∆Qs=12 and 2p=360 and 2*∆p = 4, and has six sets of stator segments, or Qs=432 and ∆Qs=12 and 2p=360 and 2*∆p = 8, and has three sets of stator segments, or Qs=432 and ∆Qs=18 and 2p=360 and 2*∆p = 12, and has three sets of stator segments.

14. The motor according to any one of claims 8 to 13, wherein, The set of windings of a group of stator segments is connected to one or two converters.

15. Wind turbine (450), including: A rotating hub (453) is provided, and multiple rotor blades (454) are mounted on the rotating hub. The motor (400) according to any one of claims 8 to 14. The rotor (402) of the motor is mechanically, in particular directly, without a gearbox, connected to the rotating hub (453).

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