Stator for synchronous motor and synchronous motor

Abstract

A stator for a synchronous motor and a synchronous motor. The invention relates to a stator or a stator segment for a synchronous machine, in particular a permanent magnet synchronous machine, comprising: a plurality of lamination stacks, each extending in a circumferential direction and a radial direction and each consisting of sheets stacked in an axial direction, the lamination stacks being arranged spaced apart in the axial direction, each lamination stack includes a yoke portion and a plurality of tooth portions protruding in a radial direction, a groove portion is formed between each pair of adjacent tooth portions, and the groove portions of the plurality of lamination stacks are aligned in a circumferential direction such that a plurality of grooves extending in an axial direction are formed, wherein a radially extending cooling fluid duct is formed axially between at least one pair, in particular each pair, of adjacent lamination stacks; the stator coils are arranged in a plurality of slots according to a centralized winding topology such that a first coil portion, in particular a first coil, and a second coil portion, in particular a second coil, are arranged in each slot.

Description

Technical Field

[0001] The present invention relates to a stator or stator segment for a synchronous machine, further to a permanent magnet synchronous motor, and still further to a wind turbine. Background Technology

[0002] In direct-drive permanent magnet (PM) generators, the higher torque density results in higher wind turbine (WT) output power, but on the other hand, it can also lead to higher temperatures due to further losses generated in the stator copper. In high-torque, low-speed PM generators, the stator windings account for the majority of the losses. Therefore, any additional increase in the generator's output is primarily limited by the temperature of the stator windings.

[0003] Due to the winding configuration in a centralized winding generator (CW), i.e., two coil sides per slot, the stator winding temperature is significantly higher than in a distributed winding (DW) generator. Therefore, increased cooling system performance will have a considerable impact on the maximum output from a CW generator (leading to increased annual power output (AEP) and insulation life). Furthermore, the higher winding temperature reduces generator component life and results in lower generator efficiency and reliability. Mitigating winding temperature in centralized winding generators is the subject of this application.

[0004] In conventional stator or permanent magnet motors, which include cooling systems, relatively high winding temperatures have been observed to impair performance and interfere with efficient generator operation.

[0005] To date, both DW and CW generators used in conventional wind turbines employ forced air cooling systems. Cold air enters the generator from the NDE and DE sides, and after passing through the stator winding head, it enters the axial gap between the rotor and stator and is distributed among multiple radial air ducts in the stator body to remove heat.

[0006] However, conventional cooling methods cannot reduce the high winding temperatures in CW generators. Therefore, CW generators experience higher temperatures than DW generators, and this issue can have a significant impact on the AEP and lifespan of the winding insulation.

[0007] Therefore, there may be a need for improved performance in stators or stator segments for synchronous motors, for synchronous motors, and for wind turbines including synchronous motors, where the maximum winding temperature can be reduced compared to conventional systems. Furthermore, the object of this invention is to improve the power output performance of the generator while meeting the temperature requirements of the generator components, particularly the windings. Summary of the Invention

[0008] This need can be met by the subject matter according to the independent claims. The dependent claims describe advantageous embodiments of the invention.

[0009] According to embodiments of the present invention, a stator or stator segment for a synchronous motor, particularly a permanent magnet synchronous motor, is provided, comprising: a plurality of lamination stacks, each lamination stack extending in a circumferential direction and a radial direction, and each lamination stack consisting of sheets stacked in an axial direction, the lamination stacks being spaced apart in the axial direction, each lamination stack including a yoke portion and a plurality of tooth portions projecting in the radial direction, a slot portion being formed between each pair of adjacent tooth portions, wherein the slot portions of the plurality of lamination stacks are aligned in the circumferential direction to form a plurality of slots extending in the axial direction, wherein radially extending cooling fluid conduits are axially formed between at least one pair, particularly each pair of adjacent lamination stacks; stator coils arranged in the plurality of slots according to a concentrated winding topology, such that a first coil portion of a first coil and a second coil portion of a second coil are arranged in each slot, wherein the first and second coil portions are arranged in at least one slot, particularly in each slot, such that a circumferential (particularly axially extending) inter-coil cooling fluid channel is provided between the two coil portions.

[0010] A stator segment spanning the entire circumference or an angle section spanning the entire circumference can be provided, or a stator consisting of multiple stator segments spanning the entire circumference can be provided. For example, the angle section can span 30°, 45°, 90°, 60°, or 180°.

[0011] The sheets in a laminated stack can be made of a high-permeability material and can be electrically isolated from each other within the stack. Depending on whether the entire stator or a stator segment is provided, the corresponding laminated stack can extend across the entire circumferential direction or an angular segment of the entire circumferential direction. Laminated stacks can be spaced apart (in the axial direction) by providing spacer elements between adjacent stacks. The axial space between laminated stacks can provide space for radially extending(one or more) cooling fluid conduits(s). Therefore, the spacers between laminated stacks may occupy only a small portion of the space between adjacent laminated stacks and thus may only marginally interfere with the function of the radially extending(one or more) cooling fluid conduits(s).

[0012] The toothed portion may project radially outward (or inward) from the yoke portion. Depending on the application, the slot or slot portion may have a rectangular or trapezoidal shape in cross-sectional view (e.g., when viewed along the axial direction). Each slot (consisting of multiple axially stacked slot portions) may accommodate a first coil portion and a second coil portion, providing a circumferential cooling fluid passage between the two coil portions. In each slot, several windings or turns of the same coil portion may be present, for example, they may be arranged radially on top of each other. In particular, the first coil portion may belong to a first phase and the second coil portion may belong to a second phase, wherein the phases may be the same or may be different.

[0013] The inter-coil cooling fluid channel can be circumferentially arranged between the first and second coil portions in the following sense: the center of the first coil portion is at a first circumferential position, the center of the second coil portion is at a second circumferential position, and the center of the inter-coil cooling fluid channel is at a circumferential position between the first and second circumferential positions.

[0014] Specifically, the first coil portion may include a plurality of turns of wire, wherein the turns are wound around a tooth (delimited to the slot on one circumferential side) a plurality of times to form a (first) coil around the tooth. The multiple turns may be arranged radially on top of each other and / or circumferentially on top of each other. The second coil portion may include a plurality of turns of wire, wherein the turns are wound around another tooth (delimited to the slot on another circumferential side) a plurality of times to form a (second) coil around other teeth.

[0015] The first coil portion is a part of a (first) coil wound on a tooth adjacent to the slot, the first coil portion being located within the slot. The second coil portion is a part of a (second) coil wound on another tooth, the other tooth demarcating the slot on another circumferential side. The first coil can be associated with the same or different phases as the second coil. Each of the first and second coils can be formed by one or more turns of winding or wire around the corresponding tooth, wherein the turns can be formed in different layers in the radial and / or circumferential directions. For example, the first / second coil can be formed by two layers of winding in the circumferential direction and multiple layers, such as 15 and 35 layers, in the radial direction. Other configurations are possible.

[0016] The radially extending cooling fluid conduits may be demarcated at least partially or entirely by the material of the laminated stack, while the inter-coil cooling fluid channels may be substantially demarcated by the respective edges of the first and second coil portions. The maximum separation between the edges of the first and second coil portions that limit the inter-coil cooling fluid channels may, for example, total between 2 mm and 10 mm in the circumferential direction. Other values ​​are possible.

[0017] Advantageously, a cooling fluid, such as compressed air, can be introduced and passed through inter-coil cooling fluid channels to absorb heat from the respective first and second coils, or first and second coil portions. The cooling fluid can be directed to flow synergistically through or within the inter-coil cooling channels and in radially extending cooling fluid conduits. For example, the cooling fluid may first be directed through one or more inter-coil cooling fluid channels and then through radially extending cooling fluid conduits, potentially via a channel through the air gap between the stator and rotor. This may depend on the specific configuration of the first and second coil portions, such as their geometric relative arrangement and / or constitution.

[0018] The stator (segment) may further include, for example, a compressor or fan for driving cooling fluid through one or more inter-coil cooling fluid channels and / or one or more radially extending cooling fluid conduits. The cooling fluid may include, for example, a gaseous fluid, such as air, particularly compressed air.

[0019] Efficient cooling of the coils, and thus the entire stator, can be achieved by providing cooling fluid channels between the coils, particularly in combination with radially extending cooling fluid conduits (formed within the lamination stack). This improves the efficiency of generators and synchronous motors during operation. Synchronous motors can be specifically configured as generators, particularly for wind turbines.

[0020] Specifically, the stator teeth may protrude radially outward, and the rotor, if present, may be an external rotor.

[0021] According to an embodiment of the invention, cooling fluid guided within the inter-coil cooling fluid channel, particularly axially guided cooling fluid, comes into direct contact with the axially extending first edge of the first and second coil portions in order to absorb heat.

[0022] When the cooling fluid comes into direct contact with the first edge extending axially from the first and second coil portions, heat can be effectively transferred at least partially from the coil to the cooling fluid in order to cool the coil.

[0023] According to an embodiment of the invention, the first and second coil portions are arranged in a slot such that the first edges of the first and second coil portions, which partially demarcate the cooling fluid passage between the coils, are parallel or inclined relative to each other, particularly according to an A-shape or a V-shape.

[0024] The first edges of the first and second coil portions can be formed by one or more of a plurality of windings of an electrical conductor, which are layered on top of each other in the radial and / or circumferential directions as mentioned above. When the first edges are parallel to each other, they are spaced apart by a distance that does not change substantially in the radial direction. If the first edges are inclined relative to each other (not parallel), the relative distance between the edges can vary depending on the radial position, such that it increases or decreases radially outward. Thus, several applications or application requirements can be met, and flexibility can be improved.

[0025] According to an embodiment of the invention, the first and second coil portions have a substantially rectangular cross-sectional shape, wherein the first and second coil portions are substantially parallel to each other or inclined relative to each other, particularly according to an A-shape or a V-shape.

[0026] Depending on the layer configuration or design of the first and second coil sections, deviations from the exact rectangular or trapezoidal cross-sectional shape may exist. In the case of multi-turn coils, the first and second coil sections may consist of substantially the same number of windings or turns of electrical conductors wound in the same or similar layer configuration in the circumferential and / or radial directions. In an A-shape configuration, the first and second coil sections have a radially outward distance (circumferential distance) from each other that is smaller than the radially inward distance. For a V-shape configuration of the winding topology designed for the first and second coil sections, the radially outward distance between the first and second coil sections can be larger than the radially inward distance. This allows for flexibility while maintaining cooling performance.

[0027] According to an embodiment of the invention, the slot has a rectangular or trapezoidal cross-section, wherein the edge of the tooth demarcating the slot is in direct contact with the axially extending second edge of the first and second coil portions.

[0028] For example, the slot shape can be selected depending on whether the first and second coil portions are provided in an A-shape or V-shape configuration. For example, when the first and second coil portions are provided in a parallel configuration, the slot can have a substantially rectangular (parallel tooth edges) shape. When the first and second coil portions are provided in an A-shape or V-shape configuration or geometry, for example, the slot can have a trapezoidal (non-parallel tooth edges) cross-sectional shape with a larger circumferential width at the radially inner side for the A-shape and at the radially outer side for the V-shape.

[0029] According to an embodiment of the invention, the stator section further includes an axially extending coil portion cover disposed at the edges of the first and second coil portions facing the air gap between the stator and the rotor.

[0030] The coil section cover provides protection for the corresponding coil section and, for certain configurations, prevents cooling fluid from passing through the inter-coil space, such as into the air gap between the stator and rotor (particularly for parallel and A-shaped coil configurations). The coil section cover may or may not have any openings.

[0031] According to an embodiment of the invention, for the parallel and A-shaped configuration of the first and second coil portions, the coil portion cover prevents cooling fluid from passing through the coil portion cover in order to avoid fluid communication between the cooling fluid channels and the air gap between the coils.

[0032] For the parallel and A-shaped configuration of the first and second coil sections, it may be advantageous to prevent cooling fluid from passing through the coil section cover, and instead guide cooling air (particularly radially inward) to radially extending cooling ducts and via these ducts to, for example, a heat exchanger to remove heat or thermal energy from the coils to improve cooling efficiency.

[0033] In the case of a V-shaped configuration, the cover opening allows the cooling fluid to pass through the opening or cover opening after at least partially passing through the inter-coil cooling fluid passage, particularly into the air gap between the stator and rotor. This is because, in a V-shaped configuration, cooling air cannot be directed radially inward, as the first and second coil portions may be very close to each other, or even in contact or touching at the radially inner ends of the respective coils, making cooling fluid passage impossible or nearly impossible. Depending on the specific application, the cover opening can have a shape or geometry. The axial spacing of the cover opening can be adapted for a specific application, and in particular, can be adapted to correspond to the relative axial spacing of the radially extending cooling fluid passages to improve the desired flow geometry of the cooling fluid.

[0034] According to an embodiment of the invention, the stator segment further includes a support frame connected to a corresponding yoke portion of the laminated stack for supporting and securing the plurality of laminated stacks.

[0035] The support frame can be located specifically in the radially inner region of the stator, while the laminations can be connected or mounted, particularly bolted or welded, to the support frame to project radially outward. The support frame provides rigidity and mechanical strength to the stator. It may not be constructed of a solid, continuous material, but can be configured as a scaffold, skeleton, or frame that provides mechanical rigidity without substantially interfering with the flow of cooling fluid. The support frame can cover or interfere with, for example, between 5% and 10% and 25% of radially extending cooling channels, and may block only a relatively small portion of radially extending cooling channels.

[0036] According to an embodiment of the invention, the stator section further includes a cooling fluid drive and guide system, particularly providing a closed cooling fluid circuit adapted to: guide cooling fluid from at least one axial end of the stator, particularly from both axial ends, into cooling fluid channels between each coil, and particularly into a region radially outward from the protruding end of the tooth, wherein an air gap will be formed particularly between the stator and the rotor to allow cooling fluid to pass axially through the cooling fluid channels between each coil and partially through radially extending cooling fluid conduits, and / or allow cooling fluid to pass axially through the air gap and partially through radially extending cooling fluid conduits.

[0037] The cooling fluid drive and guide system may include at least one fan and / or compressor for providing suction or pressure to the cooling fluid. The guide system may include a piping system, for example, leading from the fan or compressor to an axial end of the stator where the cooling fluid can be introduced (after passing through a heat exchanger). Therefore, the cooling fluid can be introduced in an axial or substantially axial direction. This allows for effective cooling.

[0038] According to an embodiment of the invention, for the parallel and A-shaped configuration of the first and second coil portions: the first cooling fluid portion is guided to and partially through the air gap, a portion of the first cooling fluid portion is guided through a radially extending cooling fluid conduit, particularly radially inward; the second cooling fluid portion is guided to and partially through the inter-coil cooling fluid channel, a portion of the second cooling fluid portion is guided through a radially extending cooling fluid conduit, particularly radially inward.

[0039] According to an embodiment of the invention, for the V-shaped configuration of the first and second coil portions: a first cooling fluid portion is guided to and partially through the air gap, a portion of the first cooling fluid portion is guided through a radially extending cooling fluid conduit, particularly radially inward; a second cooling fluid portion is guided to and partially through the inter-coil cooling fluid channel, a portion of the second cooling fluid portion is guided to the air gap and from there through a radially extending cooling fluid conduit, particularly radially inward.

[0040] Therefore, depending on the configuration of the first and second coil sections, the cooling fluid paths can be different. Thus, the cooling method can be applied to coil designs with different configurations.

[0041] According to an embodiment of the invention, the stator or stator segment further includes a heat exchanger configured to partially absorb heat from a cooling fluid conduit extending radially outward, particularly radially inward.

[0042] A heat exchanger can absorb or receive heat energy from a heated cooling fluid and thus cool the cooling fluid, which can then be supplied again to inter-coil cooling channels and / or radially extending cooling pipes for cooling a generator. For example, a heat exchanger can release heat energy to atmospheric air.

[0043] The stator segment or stator can be configured for at least one of the following: closed-loop cooling, in which case it further includes a heat exchanger configured to partially absorb heat from a cooling fluid conduit extending radially outward, particularly radially inward; and open-loop cooling, in which case it further includes a cooling fluid conduit configured to guide the cooling fluid that has absorbed heat from the stator to the environment, wherein in particular no heat exchanger is provided.

[0044] According to an embodiment of the present invention, a permanent magnet synchronous motor is provided, comprising: a stator or a plurality of stator segments according to one of the foregoing embodiments to form a stator over the entire circumference; a rotor, particularly a radially outer rotor, rotatably supported relative to the stator; wherein a radially extending radial air gap is formed between the stator and the rotor, wherein, in particular, an inter-coil cooling fluid passage communicates with a V-shaped air gap for the first and second coil portions, or wherein, in particular, the inter-coil cooling fluid passage does not communicate with an A-shaped or parallel-arranged air gap for the first and second coil portions.

[0045] According to an embodiment of the present invention, a wind turbine is provided, comprising: a permanent magnet synchronous motor according to the foregoing embodiment; and a hub having a plurality of rotor blades coupled to a rotor or a machine.

[0046] Wind turbines can be direct-drive wind turbines, where, for example, no gearbox is provided or there is no gearbox between the hub connecting the rotor blades and the generator rotor.

[0047] The aspects defined above and other aspects of the present invention will become clear from the examples of embodiments described below and will be explained with reference to these examples. The present invention will be described in more detail below with reference to examples of embodiments, but the present invention is not limited thereto. Attached Figure Description

[0048] Embodiments of the invention will now be described with reference to the accompanying drawings. The invention is not limited to the embodiments illustrated or described.

[0049] Figures 1 to 3 A stator segment according to an embodiment of the present invention is schematically illustrated in cross-sectional view;

[0050] Figure 4A stator segment according to an embodiment of the present invention is schematically illustrated in a three-dimensional view;

[0051] Figure 5 and 6 The diagram is schematically illustrated from one axial end and in cross-sectional view. Figure 4 The stator segment shown in the diagram;

[0052] Figure 7 A cross-sectional view of a permanent magnet synchronous motor according to an embodiment of the present invention is schematically illustrated.

[0053] Figure 8 and 9 A portion of an electrical machine according to an embodiment of the present invention is schematically illustrated in both cross-sectional and three-dimensional views.

[0054] Figure 10 , 11 Figures 12 and 13 schematically illustrate a portion of an electrical machine according to another embodiment of the invention in cross-sectional and three-dimensional views, respectively;

[0055] Figure 13 A wind turbine according to an embodiment of the present invention is schematically illustrated. Detailed Implementation

[0056] 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 given the same reference numerals or reference numerals that differ only in the first numeral. Description of an element not described in one embodiment may be obtained from the description of that element in another embodiment.

[0057] The stator section 100 for a synchronous motor according to an embodiment of the present invention is in Figure 1 The diagram is illustrated as a cross-sectional view taken along an axial direction 101, which is perpendicular to both the radial and circumferential directions 102 and 103. Only one of the plurality of stacks, stack 104, is shown in the cross-sectional view. Each of those stacks 104 extends in both the circumferential and radial directions 103, and the plurality of such stacks are stacked along the axial direction 101.

[0058] For example, in the illustration of a three-dimensional view of a stator segment 400 according to an embodiment of the present invention. Figure 4 As can be seen, the stacked plates 404_1, 404_2, ..., 404_n are stacked in the axial direction 401 and they are spaced apart from each other, thus forming radially extending cooling fluid channels 405_1, 405_2, ..., 405_n, which will be explained further below.

[0059] like Figure 1Each stack 104 illustrated in the figure includes a yoke portion 106 and a plurality of toothed portions 107 projecting in the radial direction 102, wherein a groove 108 portion (with a groove bottom support 108a) is formed between each pair of adjacent toothed portions 107. Multiple stacks, for example... Figure 4 In the diagram, the slot portions 108 of the stacks 404_1, 404_2, ..., 404_n are aligned in the circumferential direction 103, forming a plurality of slots 109 extending in the axial direction 101. For example, in... Figure 4 As can be seen, radially extending cooling fluid conduits (e.g., 405_1, 405_2, ..., 405_n) are formed axially between at least one pair of adjacent stacks (e.g., 404_1, 404_2).

[0060] As in Figure 1 As can be further seen, the stator coils are arranged in a plurality of slots 109, such that a first coil portion 110 and a second coil portion 111 are arranged in each slot 109. Those first and second coil portions 110, 111 are arranged in the slots 109 to provide a circumferential cooling fluid passage 112 between the two coil portions 110, 111. Figure 1 As indicated, the cooling fluid 113 can be guided in the axial direction within the inter-winding cooling fluid channel 112.

[0061] Cooling fluid 113 thus comes into direct contact with the axially extending first edge 114 of the first and second coil portions 110, 111 in order to absorb heat. Figure 1 In the embodiment illustrated in the figure, the first edges 114 of the first and second coil portions 110, 111 partially demarcate the inter-coil cooling fluid channel 112 and they are parallel to each other, at least substantially parallel to each other.

[0062] According to an embodiment of the present invention Figure 2 and Figure 3 In embodiments 200 and 300 of the stator segment illustrated in the figure (shown as shown in the figure), Figure 1 (in the view), the corresponding first edges 214 and 314 of the first and second coil portions 210, 211 and 310, 311 are inclined relative to each other, in Figure 2 In the shape of A and in Figure 3 It is tilted in a V shape.

[0063] from Figures 1 to 3 It can be understood that the first and second coil portions 110, 111; 210, 211; 310, 311 have a substantially rectangular cross-sectional shape when viewed along the axial direction 101, and they are substantially parallel to each other. Figure 1 ), or as Figure 2 and Figure 3The embodiments shown in the illustration are tilted relative to each other.

[0064] from Figure 1 , 2 Furthermore, it can be understood that the corresponding grooves 109, 209, and 309 have a rectangular shape in cross-section. Figure 1 (middle) or trapezoidal shape ( Figure 2 and 3 The cross-section of (the middle section). From... Figure 1 It can be further understood that the edge 115 of the tooth 107 demarcating the groove 109 makes direct contact with the second edge 116 extending axially and radially from the first and second coil portions 110, 111. Similarly (see...) Figure 2 , 3 The second edges 216 and 316 of the first and second coil portions 210 and 211, 310 and 311 are in direct contact with the edges 215 and 315 of the teeth 207 and 307 that demarcate the slots 209 and 309.

[0065] Figure 1 , 2 Figures 1 and 3 further illustrate axially extending coil portion covers 117, 217, and 317, which are arranged at the edges 118, 218, and 318 of the first and second coil portions 110, 111; 210, 211; 310, 311, respectively. Edges 118, 218, and 318 face the air gap 119, 219, and 319 between the stator and the rotor (not shown).

[0066] already mentioned Figure 4 A stator segment 400 according to an embodiment of the present invention is illustrated in a three-dimensional view. A first coil portion 410 belongs to a first coil 420, and a second coil portion 411 belongs to a second coil 421. A coil portion cover 417 covers the coil portions 410 and 411, which are arranged in and substantially occupy the slot 409, while the inter-coil cooling fluid channel (in) Figure 4 (Not visible in the center) is circumferentially provided between coil portions 410 and 411. For example, from... Figure 4 As can be understood, stator segment 400 has a curved shape. In this respect, note that for the sake of simplicity in the illustrations, Figure 1 , 2 The stator portions 100, 200, and 300 in 3 are illustrated in a straightened manner to provide a straight extension of the (actually curved) circumferential direction 103.

[0067] Figure 5 and Figure 6 The illustrations are presented in simplified 3D and cross-sectional views, respectively. Figure 2 Stator segment 200 is shown in the diagram. For in... Figure 1 and Figure 2 And still Figure 5 and Figure 6 The first and second coil portions 110, 111; 210, 211 in the diagram are arranged in a parallel and A-shape. The coil portion covers 117, 217 prevent the cooling fluid 113 from passing through the coil portion covers 117, 217, so as to avoid fluid communication between the inter-coil cooling fluid channels 112, 212 and the air gap 119.

[0068] Figure 7 The illustration shows a cross-sectional view of a permanent magnet synchronous motor 730 according to an embodiment of the present invention. The motor 730 includes a stator 731, which may be formed, for example, from a plurality of stator segments, such as... Figure 1 , 2 As shown in diagrams 3, 4, 5, and 6, so that the stator is formed throughout the circumference.

[0069] Furthermore, the motor 730 includes a rotor 732 rotatably supported relative to the stator 731. The rotor 732 is an outer rotor. The rotor 732 includes a plurality of permanent magnets 733 on a rotor housing 732a. Figure 7 In the cross-sectional view, only one first coil portion 710 is visible. Arrow 734 indicates the flow direction of cooling fluid 713 in the inter-coil cooling channel 712 between the two coil portions 710 and 711 (not shown), which are arranged in a slot in the stator or stator section.

[0070] Arrow 735 indicates the flow direction of cooling fluid 713 entering the air gap 719 between stator 731 and rotor 732. The rotor has a plurality of permanent magnets 733 mounted facing the radial outer surface of stator 731, wherein the air gap 719 is formed between the permanent magnets(one or more) 733 and the radial outer surface of stator 731.

[0071] Figure 7 This diagram illustrates the cooling fluid flow geometry for the parallel and A-shaped configuration of the coil sections 710 and 711 (also for comparison). Figure 1 and Figure 2 Cooling fluid entering the inter-coil cooling channel 712 in the axial direction can then partially flow through radial air pipes 705_1, 705_2, 705_n, so as to exit radially inward from the stack of laminations 704_1, 704_2...704_n according to the flow direction 736, so as to be guided to the heat exchanger 737.

[0072] The permanent magnet motor, stator, or stator segment 700, 731 includes a cooling fluid drive and guide system 740 that provides a closed cooling fluid circuit. The cooling fluid drive and guide system 740 is adapted to guide cooling fluid 713 from at least one axial end 741, 742, particularly from both axial ends 741, 742 of the stator 731, into each winding inter-winding cooling fluid passage 712, and also into a region 719 radially outward from the protruding ends of the teeth, where an air gap 719 is formed between the stator 731 and the rotor 732.

[0073] Furthermore, the cooling fluid drive and guide system 740 is adapted to allow cooling fluid 713 to pass axially through the inter-coil cooling fluid channel 712 and partially through the radially extending cooling fluid conduits 705_1, ... 705_n. The system 740 is further adapted to allow cooling fluid 713 to pass axially through the air gap 719 and partially through the radially extending cooling fluid conduits 705_1, ... 705_n.

[0074] exist Figure 7 The diagram also depicts a support frame 743 in a very schematic manner. The support frame 743 is connected to the corresponding yoke portions of the stacks 704_1, ..., 704_n, and is used to support and fix the multiple stacks.

[0075] As from Figure 7 As can be understood, by applying the parallel and A-shaped configuration of the first and second coil portions, the first cooling fluid portion 735 is partially guided to and through the air gap 719, and a portion of the first cooling fluid portion 735 is guided through radially extending cooling fluid conduits 705_1, ... 705_n, particularly radially inward. Furthermore, the second cooling fluid portion 734 is guided to and partially through the inter-winding cooling fluid channel 712, wherein a portion of the second cooling fluid portion is guided through radially extending cooling fluid conduits 705_1, ... 705_n, particularly radially inward. Figure 7 (Middle to bottom).

[0076] The heat exchanger 737 is configured such that the cooling fluid 713 partially absorbs heat from the radially extending cooling fluid conduits 705_1, ... 705_n, particularly radially inward.

[0077] The cooling drive system 740 may include, for example, a fan 744 configured to draw or compress cooling air through a heat exchanger 737. The cooling fluid drive system 740 may further include a duct section 745, for example for guiding cooling fluid to axial ends 741, 742, and from there into the inter-coil cooling passage 712 and into the air gap 719.

[0078] Figure 8 and Figure 9 A further embodiment of the motor 830 according to an embodiment of the present invention is illustrated to show the flow path of the cooling fluid in more detail. The cooling fluid is introduced into the inter-coil cooling channel 812 according to the axial direction indicated by arrow 834, and is further introduced into the air gap 819, indicated by arrow 835 indicating the flow direction of the cooling fluid. The cooling fluid exits from the air gap 819 according to direction 836_1 through radially extending cooling pipes 805_1, 805_2, 805_n. Furthermore, cooling air exits radially inward from or out of the inter-coil cooling channel 812 again according to the flow direction 836_2 through radially extending cooling air pipes 805_1, ... 805_n. The exit portions 836_1, 836_2 then enter as cooling air 836 into a heat exchanger (not shown) and cooling fluid drive system 740.

[0079] Figure 8 and Figure 9 The flow direction path shown in the diagram is applied to both the A-shaped configuration and the parallel configuration in a manner similar to that of the first and second coil portions 810, 811.

[0080] Figure 10 , 11 Figures 1 and 12 illustrate a corresponding motor 1030, which includes a stator section 1000 in a V-shaped configuration for the first and second coil sections. Herein, the flow path of the cooling fluid differs from that of the parallel and A-shaped configurations. Similar to the parallel and A-shaped configuration, cooling air is introduced axially into the inter-coil cooling channel 1012 according to flow direction 1034. Furthermore, cooling fluid is also introduced axially into the air gap 1019, as indicated by flow direction 1035. However, unlike the flow path configuration illustrated for the parallel and A-shaped configuration, the cooling fluid exits radially outward from the inter-coil cooling channel 1012 according to the cooling flow direction 1050 to reach the air gap 1019, where it can flow partially axially and / or partially circumferentially. The cooling fluid then exits radially inward from the air gap 1019 (through radial cooling conduits) according to flow direction 1036, wherein the cooling fluid according to flow direction 1036 includes the cooling fluid that has already passed through the inter-coil cooling channel 1012 and partially through the air gap 1019.

[0081] Figure 11 and 12 Configured separately for V-shapes (e.g., as in...) Figure 10 The diagram shows the cover openings 1051 and 1151 in the coil section covers 1017 and 1117, respectively. Figure 11 The cover opening 1051 is formed by an axially extending slit, while Figure 12The cover opening 1151 shown in the diagram is formed by a circumferentially extending slit. Other cover opening shapes are possible. Cover openings 1051 and 1151 allow cooling fluid to exit radially outward from the inter-coil cooling channel 1012 to enter the air gap 1019. Figure 11 and 12 The cooling fluid is shown in the diagram (not illustrated).

[0082] For the V-shaped configuration of the first and second coil portions, the first cooling fluid portion 1035 is guided to and partially passes through the air gap 1019, and a portion of the first cooling fluid portion is guided through the radially extending cooling fluid conduit 1005, for example, according to Figure 10 The fluid flow direction 1036 shown in the diagram is radially inward. The second cooling fluid portion 1034 is guided to and partially passes through the inter-winding cooling fluid channel 1012, and a portion of the second cooling fluid portion is guided to the air gap 1019 and from there through the radially extending cooling fluid conduit 1005, particularly radially inward.

[0083] Radially extending cooling fluid conduits exist Figure 1 , 2 In the embodiment illustrated in Figure 3, however, the cross-sectional view is obscured.

[0084] Figure 13 A wind turbine according to an embodiment of the present invention is schematically illustrated. The wind turbine 1360 includes a permanent magnet synchronous motor 1330 according to an embodiment of the present invention and a hub 1361 having a plurality of rotor blades 1362, wherein the hub 1361 is coupled to the rotor 1332 of the permanent magnet synchronous motor 1330, the permanent magnet synchronous motor 1330 further including a stator 1331. The generator 1330 is arranged within a nacelle 1363, which is mounted on top of a wind turbine tower 1364.

[0085] Embodiments of the present invention increase heat dissipation directly from the centralized winding coil to the cooling airflow. Thus, the cooling airflow can enter the axial channels 112, 212, 312 between the two coils in the slot. As a result, the cooling air is forced to have a surface in direct contact with the hot spot location. This can lead to heat being transferred directly from the winding to the cooling air, and consequently, a significant reduction in the winding temperature (hot spot).

[0086] exist Figure 1 In this design, two coils are placed parallel to each other in a slot at a certain distance, creating a gap between the sides of the two coils. Figure 2 In the middle, two coils are placed in the slot in an A-shape to create a gap between the two coil sides. Figure 3In this configuration, two coils are placed in a slot in a V-shape to create a gap between the two coil sides. This gap can be maintained by means of a temporary or permanent tube separation, which can be installed before, during, or after the coil insertion.

[0087] exist Figure 1 In the middle, the cooling channels 112 between the slots or coils are parallel. It is worth noting that, in Figure 1 In the middle, groove 109 is parallel, while... Figure 2 and 3 In the middle, grooves 209 and 309 are not parallel, and the most suitable design is based on the optimal dimensions.

[0088] As in Figure 7 As illustrated in the diagram, the cooling method is based on forced air cooling. The cooling system can be a closed air cooling loop and / or an open loop (direct cooling). Cooling air or general cooling fluid can enter the generator from the non-drive end side and / or the drive end side (representing the axial ends of the stator), and after passing over the stator winding head, it enters the axial gap between the rotor and stator and then into the channel between the coils, and then it is distributed through radial air ducts in the stator.

[0089] In parallel and A-shaped configurations (e.g. in...) Figure 8 and 9 In the diagram, airflow enters from the two axial ends into the axial channel between the two coil sides and exits through a radial air duct, whereas in the V-shaped configuration (see, for example, see...) Figure 10 , 11 In step 12), airflow enters the axial channel between the two coils from both axial ends, but exits through an increased gap (also called a wedge) in the coil cover to join the main air cooling fluid in the air gap between the rotor and stator. Finally, the airflow in the main air gap, combined with the exhaust airflow from the channel between the two coils, is distributed among multiple radial air channels in the stator body (see, for example, [reference 12]). Figure 10 ). Figure 11 and 12 Different shapes of air outlets flowing in a channel between two coils are shown. The outlet area can be designed in the axial or tangential direction. The size, number, and distribution of outlets 1051, 1151 can be flexible, thus allowing for sufficient flow, for example, inside the duct, to achieve optimal performance.

[0090] Simulations show that, for the A-shape configuration, the winding temperature (hot spot) is effectively reduced. The reduction in coil temperature achieved, as described in the embodiments of the invention, can lead to an increase in generator power for the same generator size, particularly for wind farms with high ambient temperatures. Furthermore, the embodiments provide a considerable impact and significant advantages regarding winding insulation life.

[0091] Embodiments of the present invention may provide one or more of the following features:

[0092] • The larger contact area between the coil and the cooling air results in higher heat transfer and thus higher cooling performance.

[0093] The heat system may still be based on forced air cooling, thus supporting conventional cooling systems.

[0094] 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 the reference numerals in the claims should not be construed as limiting the scope of the claims.

Claims

1. A stator (731) or stator segment (100, 200, 300) for a synchronous motor (730), particularly a permanent magnet synchronous motor, comprising: Multiple stacks of sheets (704_1, 704_2, 704_n) extend in a circumferential direction (103) and a radial direction (102), and each stack consists of sheets stacked in an axial direction (101), the stacks being arranged at intervals in the axial direction, each stack including a yoke portion (106) and multiple toothed portions (107) protruding in the radial direction (102), with a groove portion (108) formed between each pair of adjacent toothed portions (107). The groove portions of the plurality of stacked sheets are aligned in the circumferential direction (103) to form a plurality of grooves (109) extending in the axial direction. Among them, a radially (102) extending cooling fluid conduit (405_1, ... 405_n) is formed axially (101) between at least one pair, particularly each pair of adjacent stacks (704_1, 704_2, 704_n); The stator coils (420, 421) are arranged in multiple slots according to a concentrated winding topology, such that, in particular, the first coil portion (110) of the first coil and the second coil portion (111) of the second coil are arranged in each slot (109). The first and second coil portions (110, 111) are arranged in at least one slot, particularly in each slot, such that a coil cooling fluid passage (112) extending particularly axially is provided between the two coil portions (110, 111), particularly circumferentially (103).

2. The stator or stator segment according to the preceding claim, wherein, Cooling fluid (113, 134) guided within the inter-coil cooling fluid channel (112), particularly axially guided cooling fluid (113, 134), comes into direct contact with the axially extending first edge (114) of the first and second coil portions (110, 111) in order to absorb heat.

3. The stator or stator segment according to the preceding claims, wherein, The first and second coil portions (110, 111) are arranged in the slot such that the first edges (114) of the first and second coil portions (110, 111), which partially demarcate the cooling fluid channel (112) between the coils, are parallel or inclined relative to each other, in particular according to an A-shape or a V-shape.

4. The stator or stator segment according to any one of the preceding claims, in, The first and second coil portions (110, 111) have a substantially rectangular cross-sectional shape. The first and second coil portions (110, 111) are substantially parallel to each other or inclined relative to each other, in particular according to an A-shape or a V-shape.

5. The stator or stator segment according to any one of the preceding claims, wherein, The groove (109) has a rectangular or trapezoidal shape in cross-section, wherein the edge (115) of the tooth (107) that demarcates the groove (109) is in direct contact with the axially extending second edge (116) of the first and second coil portions (110, 111).

6. The stator or stator segment according to any one of the preceding claims, further comprising: An axially extending coil portion cover (117) is arranged at the edge of the first and second coil portions (110, 111) facing the air gap (119) between the stator (731) and the rotor (732).

7. The stator or stator segment according to the preceding claim, wherein, For the parallel and A-shaped configuration of the first and second coil portions (110, 111), the coil portion cover (117) prevents cooling fluid from passing through the coil portion cover in order to avoid fluid communication between the inter-coil cooling fluid channel (112) and the air gap (119).

8. The stator or stator segment according to claim 6, in, For the V-shaped configuration of the first and second coil portions (310, 311), the coil portion cover (317) includes a cover opening (1051, 1151), particularly axially and / or circumferentially extending slits, allowing cooling fluid to pass through the coil portion cover (1017, 1117) to allow fluid communication between the inter-coil cooling fluid passage and the air gap, and / or The cover openings (1051, 1151) have a relative axial interval between 0.8 and 1.2 of the relative axial spacing of the radially extending cooling fluid conduits, and in particular have an axial offset relative to the radially extending cooling fluid conduits between 0.4 and 0.6 of the relative axial spacing of the radially extending cooling fluid conduits.

9. The stator or stator segment according to any one of the preceding claims, further comprising: A support frame (743) is connected to the corresponding yoke portion (106) of the stack (104) for supporting and securing the plurality of stacks.

10. The stator or stator segment according to any one of the preceding claims, further comprising: A cooling fluid drive and guide system (740), particularly providing a closed cooling fluid circuit, is suitable for: Cooling fluid (713) is guided from at least one axial end (741, 742) of the stator, particularly from both axial ends, into the inter-coil cooling fluid channel (712), and particularly into the region radially outward from the protruding end of the teeth, wherein, in particular, an air gap (719) will be formed between the stator and the rotor. To allow the cooling fluid to pass axially through the inter-coil cooling fluid channel (712) and partially through the radially extending cooling fluid conduit (705), and / or This allows the cooling fluid to pass axially through the air gap (719) and partially through the radially extending cooling fluid conduit (705).

11. The stator or stator segment according to any one of the preceding claims, in, For the parallel and A-shaped configuration of the first and second coil portions: A first portion of cooling fluid (835) is guided to and partially through an air gap (819), and a portion (836_1) of the first portion of cooling fluid is guided through a radially extending cooling fluid conduit, particularly radially inward. The second cooling fluid portion (834) is guided to and partially through the inter-coil cooling fluid channel (812), and a portion (836_2) of the second cooling fluid portion is guided through a radially extending cooling fluid conduit, particularly radially inward.

12. The stator or stator segment according to any one of the preceding claims, in, For the V-shaped configuration of the first and second coil sections: A first portion of the cooling fluid (1035) is guided to and partially through the air gap (1019), and a portion (1036) of the first portion of the cooling fluid is guided through a radially extending cooling fluid conduit, particularly radially inward. The second cooling fluid portion (1034) is directed to and partially passes through the inter-coil cooling fluid channel (1012), and a portion (1050) of the second cooling fluid portion is directed to the air gap (1019) and from there through a radially extending cooling fluid conduit, particularly radially inward.

13. The stator or stator segment according to any one of the preceding claims, configured for at least one of the following: Closed-loop cooling, in this case, further includes a heat exchanger (737) configured as a cooling fluid conduit (705) extending radially from the outlet, particularly radially inward, whereby the cooling fluid partially absorbs heat; Open-loop cooling, in this case, further includes a cooling fluid conduit configured to guide cooling fluid with absorbed heat from the stator to the environment.

14. A permanent magnet synchronous motor (730), comprising: The stator (731) or multiple stator segments (100) according to any one of the preceding claims are used to form the stator in the entire circumferential direction; The rotor (732), particularly the radially outer rotor, is rotatably supported relative to the stator and includes a plurality of permanent magnets; A radial air gap (719) extending circumferentially and axially is formed between the stator (731) and the rotor (732). Specifically, the inter-coil cooling fluid channel (712) communicates with the V-shaped air gap (719) for the first and second coil portions, or Specifically, for the A-shape or parallel configuration of the first and second coil portions, the cooling fluid channel between the coils is not in communication with the air gap.

15. A wind turbine (1360), comprising: The permanent magnet synchronous motor (1330) according to the preceding claims; A hub (1361) having multiple rotor blades (1362) coupled to a rotor (1332) or the motor (1330).

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