Winding for the stator of a rotating electrical machine

Abstract

Winding for a rotating electrical machine stator. Winding (10) for a rotating electrical machine stator (1), comprising winding legs (12) for extending into stator slots and a plurality of coil heads (13), one coil head (13) connecting two winding legs (12), the winding comprising one or more cooling fins (20) on at least one coil head (13) of the plurality of coil heads and / or on the side of the stator opposite the coil heads (13). Figure for the abbreviation: Fig. 3

Description

Title of the invention: Winding for a rotating electrical machine stator technical field

[0001] The present invention relates to rotating electrical machines and, more particularly, to the stators of such machines. The invention relates more particularly to a winding for such stators, as well as to an electrical conductor intended to be inserted into slots in such a stator. The invention also relates to the stator and the corresponding rotating electrical machine. It further relates to the method of manufacturing such windings or electrical conductors.

[0002] The invention relates more particularly to synchronous or asynchronous machines, with alternating current. It concerns in particular traction or propulsion machines for flying machines, and for the production of energy, particularly in the aeronautical field. Previous technique

[0003] A stator in which the electrical conductors extending into the stator slots are connected by conductive bridges manufactured at least in part by additive manufacturing is known from applications WO 2019 / 233786, WO 2023 / 242164 and WO 2023 / 006612.

[0004] In US patent applications 2022 / 0263392 and WO patent applications 2022 / 029008, the winding assembly is carried out by additive manufacturing. In WO patent applications 2022 / 248659 and WO patent applications 2023 / 242164, cooling channels are provided in association with electrical conductors.

[0005] Application DE 102023108423 relates to a connecting piece for electrical conductors extending into the notches of the stator.

[0006] There is a need to further improve the cooling of electrical conductors, particularly when these are manufactured at least partially by additive manufacturing. In particular, there is a need for a rotating electrical machine stator that is easy to assemble, allowing for efficient filling of slots while ensuring satisfactory electromagnetic performance.

[0007] There is still a need to reduce the manufacturing cost of electrical machines, in particular by simplifying the manufacture of the stator winding, for example by minimizing the number of parts to be used.

[0008] There is also a need to further improve the stators of electrical machines, and in particular to reduce torque ripple and AC Joule losses by induced currents, vibrations and electromagnetic noise, and to improve their reliability.

[0009] There is also a need for a process for manufacturing electrical conductors that allows the formation of electrical conductors with a satisfactory slot filling rate, enabling rapid manufacturing of electrical conductors, limiting the quantity of electrical conductors used and capable of being cooled efficiently. Description of the invention

[0010] The invention aims to meet all or part of these needs, and it achieves this, according to a first aspect, by means of a winding for a rotating electrical machine stator, comprising winding legs intended to extend into notches in the stator and a plurality of coil heads, a coil head connecting two winding legs, the winding comprising one or more cooling fins on at least one coil head of the plurality of coil heads and / or on the side of the stator opposite the coil heads.

[0011] The presence of the cooling fins improves the cooling of the winding and in particular helps to better dissipate the heat produced in the winding, especially in the coil heads and in the legs thereof.

[0012] The presence of the cooling fins increases the exchange surface area between the coil heads and a cooling circuit.

[0013] Furthermore, it is advantageous to increase the filling with conductive material in the coil heads rather than leaving space for a coating resin which has a thermal conductivity much lower than copper or other conductive material.

[0014] Thus, the temperature difference between the core of the coil heads and the external part of them which is in contact with the cooling circuit can be reduced.

[0015] The winding legs can be straight. They can be extended on either side outside the notches by an oblique part. Summary of the invention Cooling fins

[0016] At least one coil head of the plurality of coil heads may include one or more cooling fins. The winding may further include one or more cooling fins on the side of the stator opposite the coil heads.

[0017] The fins, or even the coil heads, or even the entire winding, can be manufactured by additive manufacturing. This eliminates electrical connections in the winding, which is advantageous because these can lead to hot spots and therefore points of failure, which can result in a degradation of reliability.

[0018] The fins, or even the coil heads, or the entire winding, can be made of an electrically conductive material. The fins, or even the coil heads, or the entire winding, can also be made of a thermally conductive material. The thermal conductivity of the fins allows the heat produced in the winding to be conducted to them, and thus dissipated more easily. The fins, or even the coil heads, or the entire winding, can notably be made of copper.

[0019] At least one fin, or even all of the fins, can be configured so that an electric current does not pass through them when an electric current flows through the winding. Since no electric current flows through the cooling fins, losses in them are avoided.

[0020] For this purpose, the cooling fins may have a general shape with several sides, for example substantially rectangular with four sides, of which only one side is connected to the rest of the winding, and with the other sides not electrically connected.

[0021] Thus, the fins are designed so as not to conduct electrical current. They thereby ensure a low level of AC losses, i.e. the losses associated with the skin effect for higher frequencies.

[0022] Such an arrangement of the winding and the electrically insulated cooling fins can prevent partial discharges between the conductors of different phases and between the conductors and ground, which is advantageous.

[0023] The cooling fin(s) can extend over a circumferential surface.

[0024] At least one cooling fin may be disposed on the side of the stator opposite the coil heads. At least one fin disposed on the side of the stator opposite the coil heads may, in particular, have a flattened shape, extending in particular along a flattened surface. The flattened surface may be circumferential.

[0025] In one embodiment, when moving circumferentially, every other leg of the winding may include such a cooling fin. This cooling fin may extend circumferentially, overlapping the leg to which it is connected and an adjacent leg. These fins may be located on the outer side of the stator, opposite the central bore.

[0026] Alternatively or additionally, the winding may include a plurality of cooling fins, each arranged in line with a leg of the winding, and only superimposed on said leg, in particular without protruding above an adjacent leg.

[0027] Alternatively or additionally, the winding may also include a plurality of cooling fins, each arranged in line with several legs of the winding, on the side of a central bore of the stator.

[0028] The winding may further include, on the stator side opposite the coil heads, a cooling fin disposed at the intersection of a leg and a cooling fin extending from a leg of the winding, said fin forming, in particular, a raised section of the leg at the connection between the leg and the fin extending from it. The cooling fin can thus take the form of a raised section of the leg at the connection between the leg and the fin extending from it.

[0029] This cooling fin allows the available space to be occupied by the winding material, in particular copper, rather than by impregnation or insulation material, in particular a resin, which allows for better dissipation of the heat produced in the winding. It can form a thermal bridge.

[0030] In one embodiment, the winding may include, on the side of the stator opposite the coil heads, cooling fins extending parallel to each other, with, when moving radially, first on the side of the central bore a cooling fin arranged in line with several legs, then in the middle a cooling fin arranged in line with one leg of the winding, and finally on the side opposite the central bore, a cooling fin extending circumferentially in superposition on the leg to which it is connected, and on an adjacent leg.

[0031] At least one fin may be disposed on the top of a reel head. At least one fin disposed on the top of a reel head may, in particular, have a flattened shape, extending in particular along a flattening surface. The flattening surface may be circumferential.

[0032] At least one coil head, or even a majority of coil heads, or preferably each coil head, may include at least one cooling fin, or even two cooling fins, or preferably three cooling fins. The cooling fins of a single coil head may extend parallel to each other. They may extend along flattening planes that are parallel to each other.

[0033] The winding may include a cooling fin disposed at the intersection of a leg and a coil head, in particular a raised section of the leg at the connection between the leg and the coil head. The cooling fin may take the form of a raised section of the leg at the connection between the leg and the coil head.

[0034] This cooling fin allows the available space to be occupied by the winding material, in particular copper, rather than by impregnation or insulation material, in particular a resin, which allows for better dissipation of the heat produced in the winding. It can form a thermal bridge.

[0035] Alternatively, independently or in combination with the above, the winding may include one or more fins on an oblique portion arranged in line with a winding leg, particularly on the side of the coil heads or on the side opposite the coil heads. A fin may have a rectangular shape. Alternatively, or additionally, a fin may have a trapezoidal shape.

[0036] In one embodiment, the winding comprises several layers of winding legs, in particular 2, 4, or 6, or other. The 'number of layers' refers to the number of radially arranged electrical conductors in a stator slot, through which a current flows in a different direction or of a different phase. The cooling of the layers, particularly the central layers, is enhanced by the presence of cooling fins. Electrical conductor

[0037] The winding may comprise a plurality of electrical conductors, each electrical conductor being I-shaped or U-shaped. Each U-shaped electrical conductor may have first and second legs designed to extend axially into first A and second R slots in the stator, respectively. The first and second legs may be straight.

[0038] A coil head may include a portion of a coil connected to the first and second legs of the electrical conductor, each by an oblique portion. The oblique portions may, for example, be straight.

[0039] Electrical conductors can be connected together to form the winding, for example by additive manufacturing. This eliminates the connections between the different electrical conductors, which is advantageous because these connections can lead to hot spots and therefore points of failure, which can result in a degradation of reliability.

[0040] The invention relates in particular to an electrical conductor for a rotating electrical machine stator, comprising first and second legs intended to extend into notches in the stator and a coil head connecting the first and second legs, the electrical conductor comprising one or more cooling fins on the coil head and / or on the side of the stator opposite the coil head.

[0041] The cooling fins may be as described above.

[0042] Electrical conductors, or even a majority of the electrical conductors, extend axially within the notches. The electrical conductors may be introduced into the corresponding slots by one or both axial ends of the machine, or by a central bore of the stator.

[0043] An I-shaped electrical conductor has two axial ends, each located at one of the axial ends of the stator. It passes through a single slot and can be connected or welded at each of its axial ends to two other electrical conductors at the axial ends of the stator. The stator may, for example, comprise 6, 10, 12, 14, 18, 22, or 26 I-shaped electrical conductors, with the other electrical conductors all being U-shaped. Alternatively, the stator may not have an I-shaped electrical conductor.

[0044] A U-shaped electrical conductor has two axial ends, both located at one of the axial ends of the stator. These two axial ends are defined by the two legs of the U. It passes through two different slots and can be connected or welded at each of its axial ends to two other electrical conductors on the same axial side of the stator. The bottom of the U, that is, the side of the U forming the coil head, is located on the other axial side of the stator.

[0045] At least some, or even a majority, of the electrical conductors may be U-shaped.

[0046] The electrical conductors may be made of copper or aluminum, or any other conductive material enamelled or coated with any other suitable insulating coating. Stator

[0047] The invention also relates, according to another aspect, independently or in combination with the foregoing, to a stator comprising a stator mass having slots, and a winding housed in the stator mass. The winding may be as defined above. It may comprise a plurality of electrical conductors housed in the slots, at least some of the electrical conductors, or even a majority of the electrical conductors, or better yet, all of the electrical conductors, being as defined above.

[0048] The invention thus relates to a stator for a rotating electrical machine, comprising a winding or one or more electrical conductors as described above. The cooling fins may be as described above.

[0049] The stator mass has teeth defining the notches between them, the teeth being attached to a stator yoke.

[0050] The first and second notches may be non-consecutive. They can be referred to respectively as the forward notch and the return notch. The first A and second R notches may be separated by a number of notches between 3 and 20, preferably between 6 and 16, for example, 7, 8, 9, 10 or 11 notches.

[0051] The stator may have two, four, or six electrical conductors per slot. The electrical conductors may form a distributed winding. The winding may be corrugated or interlocked.

[0052] The stator mass can be made by stacking laminations. The teeth can be connected to each other by a yoke. The slots can be open or closed. They can be made entirely by cutting from the laminations. Each lamination in the stack can be a single piece. Each lamination is, for example, cut from a sheet of magnetic steel or steel containing magnetic steel, for example, steel 0.1 to 1.5 mm thick. The laminations can be coated with an electrically insulating varnish on their opposite faces before being assembled in the stack. Electrical insulation can also be achieved by heat-treating the laminations, if necessary.

[0053] Alternatively, the stator mass can be manufactured by additive manufacturing, in particular from a magnetic powder.

[0054] The rotating electrical machine may include a rotor. Cooling shell

[0055] The invention also relates, according to another of its aspects, independently or in combination with the above, to a cooling shell for a stator of a rotating electrical machine as defined above.

[0056] The invention relates in particular to a cooling shell for a rotating electrical machine stator, in particular as defined above, comprising a general circular shape and at least one circumferentially extending cooling fluid circulation portion, provided by two circumferentially extending walls.

[0057] By "extending circumferentially" is meant extending substantially along a surface having a general cylindrical or conical shape. An axis of the cylinder or cone may be an axis of rotation of the machine.

[0058] The cooling shell is intended to be placed on the winding on the side of the coil heads.

[0059] The cooling shell can be configured to fit the outer part of the coil heads while minimizing its wall thickness to reduce the temperature difference between the copper and the cooling circuit, such as a coolant. The material and wall thickness of the shell can be chosen to provide electrical insulation and prevent partial discharges. The circulation portion(s) can fit the fins to better cool the inner part of the coil heads. The presence of the circulation portions improves cooling of the winding interior.

[0060] The cooling shell may include one, two or more circumferentially extending portions of cooling fluid circulation, each provided by two circumferentially extending walls.

[0061] The circulation sections can be linked together, the shell having a spiral shape, particularly in multi-story construction.

[0062] The cooling shell may include an outer skirt, the outer skirt extending substantially cylindrically. The cooling shell may include an inner skirt, the inner skirt extending substantially cylindrically. The outer and inner skirts may be concentric. The circulation portion(s) may extend between the inner and outer skirts.

[0063] In one embodiment, the cooling shell may include an outer skirt and an inner skirt, which are notably concentric, and one or more portions of circulation of a cooling fluid extending circumferentially, each provided by two walls extending circumferentially, the portion or portions of circulation extending between the inner skirt and the outer skirt.

[0064] The walls of the circulation portions can come to fit the fins of the winding, which improves cooling.

[0065] For example, in the case where the winding comprises four layers, the cooling shell may have two circulation sections. Such a configuration allows for effective cooling of the two central layers. The two circulation sections may be arranged respectively between two circumferential rows of fins, said circumferential rows being concentric and consecutive.

[0066] Two walls defining a portion of circulation may have a distance between them, in particular between 1 and 10 mm, or even between 2 and 8 mm, better between 2 and 5 mm, being for example of the order of 3 mm.

[0067] The circulation portion(s) are designed to be positioned between cooling fins when the cooling shell is placed on the stator with the winding. The cooling shell then conforms to the shape of the coil heads. The stator may, for example, have three parallel fins and two intervening circulation portions.

[0068] The cooling shell can perform three functions. It electrically isolates the coil heads from the heat transfer fluid while ensuring good heat transfer between them. Finally, it provides the cooling fluid with sufficient circulation velocity around the coil heads to ensure a good heat exchange coefficient while limiting pressure losses, recirculation losses, and overheating of the fluid at the coil heads.

[0069] The cooling fluid may in particular be liquid, for example oil or water. Rotating electric machine

[0070] The invention also relates, according to another of its aspects, independently or in combination with the above, to a rotating electrical machine comprising a stator as defined above, and in particular a rotor. Manufacturing process

[0071] The invention also relates, according to another of its aspects, independently or in combination with the above, to a method of manufacturing a winding or an electrical conductor for a stator of a rotating electrical machine as defined above.

[0072] The invention relates in particular, according to another of its aspects, independently or in combination with the foregoing, to a method of manufacturing a winding or an electrical conductor for a stator of a rotating electrical machine, comprising the following steps: (a) supply electrical conductors, including those manufactured by additive manufacturing, including those in the shape of I-pins or U-pins, (b) deposit, in particular by additive manufacturing, on said electrical conductors, a plurality of coil heads connecting the electrical conductors, forming, in particular by additive manufacturing, one or more cooling fins on at least one coil head and / or on the side of the stator opposite the coil heads.

[0073] The cooling fins may be as described above. Flying machine

[0074] The invention also relates, independently or in combination with the foregoing, to a flying machine comprising a rotating electrical machine as described above, for extraterrestrial applications, particularly aeronautical ones. The flying machine may be chosen from the following list, which is not exhaustive: airplane, drone, airship, stratospheric aircraft, helicopter. Brief description of the drawings

[0075] The invention will be better understood upon reading the detailed description that follows, a non-limiting example of its embodiment, and upon examination of the accompanying drawing, in which:

[0076] [Fig-1] Fig. 1 is a schematic and partial perspective view of a stator in accordance with the invention.

[0077] [Fig.2] The [Fig.2] is a longitudinal cross-sectional view of the winding and cooling shell of the stator of the [Fig.1].

[0078] [Fig.3] Fig.3 illustrates a schematic and partial perspective view of the winding with cooling fins.

[0079] [Fig.4] The [Fig.4] is a schematic and partial perspective view of a part of the winding with coil heads and cooling fins.

[0080] [Fig.5] The [Fig.5] presents an isolated perspective, schematic and partial view of a U-shaped electrical conductor with cooling fins.

[0081] [Fig.6] Fig.6 shows a schematic and partial perspective view of part of the winding with electrical conductors and cooling fins.

[0082] [Fig.7] The [Fig.7] is a schematic and partial perspective view of a portion of the winding on the side opposite the coil heads.

[0083] [Fig.8] The [Fig.8] is a schematic and partial perspective view of a portion of the winding on the side opposite the coil heads of an embodiment variant.

[0084] [Fig.9] The [Fig.9] is a schematic and partial perspective view of a portion of the winding on the side opposite the coil heads of an embodiment variant.

[0085] [Fig. 10] The [Fig. 10] is a schematic and partial perspective view of the insulated cooling shell.

[0086] [Fig. 11] The [Fig. 11] is a schematic and partial exploded perspective view of the stator and cooling shells. Detailed description

[0087] Figures 1 to 7 illustrate a stator 1 of a rotating electrical machine comprising a stator and a rotor. The stator comprises a stator mass having slots and teeth defining the slots, the teeth being attached to a yoke.

[0088] The stator 1 comprises a winding 10 having electrical conductors 11 housed in slots and a cooling shell 30. In the example described, the stator has four electrical conductors per slot.

[0089] Electrical conductors have a generally rectangular cross-section. In the example described, they are radially superimposed in a single row. The circumferential dimension of an electrical conductor corresponds approximately to the width of a notch.

[0090] The electrical conductors 11 are made of copper or aluminum, or any other conductive material enamelled or coated with any other suitable insulating coating.

[0091] The electrical conductors are U-shaped, as seen in [Fig. 5]. Each has first and second winding legs 12 designed to extend axially into first A and second R slots in the stator, respectively. The winding legs 12 are straight.

[0092] The winding 10 also includes a plurality of coil heads 13. A coil head 13 connects two winding legs 12.

[0093] The winding 10 has several cooling fins 20. These are located on the one hand on the coil heads 13 and on the other hand on the side of the stator opposite the coil heads 13, as illustrated in figures 3 to 7.

[0094] The cooling fins 20 and the coil heads 13 can be manufactured by additive manufacturing. The cooling fins 20 have a generally rectangular shape, with four sides, one of which is connected to the rest of the winding 10, and three sides not electrically connected.

[0095] Fins 20 are arranged on the top of a coil head 13, as illustrated in Figures 3 to 5. They have a flattened shape, extending along a circumferential flattening surface. In the example described, each coil head 13 has three cooling fins 20. The cooling fins 20 of the same coil head 13 extend parallel to each other, along flattening planes that are parallel to each other.

[0096] The winding 10 also includes cooling fins 20 arranged at the intersection of a leg 12 and a coil head 13, as illustrated in [Fig. 4]. This cooling fin 20 takes the form of an overthickness of the leg 12 at the connection between the leg 12 and the coil head 13. This cooling fin 20 allows the available space to be occupied by the winding material 10, in particular copper, rather than by impregnation or insulation material, in particular a resin.

[0097] Fins 20 are also arranged on the side of the stator opposite the coil heads 13, as illustrated in Figures 6 and 7. They have a flattened shape, extending along a circumferential flattening surface.

[0098] In the illustrated embodiment, every other leg of the winding 10 has a cooling fin 20 which extends circumferentially over the leg 12 to which it is connected, and over an adjacent leg, as seen in [Fig. 6]. Said fins 20 are located on the outer side of the stator, opposite the central bore.

[0099] Additionally, the winding 10 comprises a plurality of cooling fins 20 each arranged in the extension of a leg 12 of the winding 10, and only superimposed on said leg 12, without protruding above an adjacent leg, as seen in [Fig.7].

[0100] Additionally, the winding 10 further comprises a plurality of cooling fins 20 each arranged in the extension of several legs 12 of the winding 10, on the side of a central bore of the stator, as seen in Figures 6 and 7.

[0101] The winding 10 further comprises, on the side of the stator opposite the coil heads 13, a cooling fin 20 disposed at the intersection of a leg 12 and a cooling fin 20 arranged in line with a leg 12 of the winding 10, as illustrated in Figures 6 and 7. The cooling fin 20 is formed by a raised section of the leg 12 at the connection between the leg 12 and the fin 20 arranged in line with it. This cooling fin 20 allows the available space to be occupied by the winding material 10, in particular copper, rather than by impregnation or insulation material, in particular a resin.

[0102] Thus, in the illustrated embodiment, the winding 10 comprises, on the stator side opposite the coil heads 13, cooling fins 20 extending parallel to each other. Moving radially, one first finds, on the side of the central bore, a cooling fin 20 arranged in line with several legs 12. Then, in the middle, a cooling fin 20 arranged in line with one leg 12 of the winding 10. Finally, on the side opposite the central bore, a cooling fin 20 extends circumferentially, overlapping the leg 12 to which it is connected, and an adjacent leg 12.

[0103] In one embodiment, the winding 10 may further comprise a cooling fin 20 on an oblique portion arranged in line with a leg 12 of the winding 10, as illustrated in Figures 8 and 9. This may be on the side of the coil heads 13 or on the side opposite the coil heads 13. A fin 20 may have a rectangular shape, as illustrated in [Fig. 8]. Alternatively, or additionally, a fin 20 may have a trapezoidal shape, as illustrated in Figures 8 and 9.

[0104] We will now describe in more detail the cooling shell 30. This shell has a generally circular shape and two circulation portions 31 of a cooling fluid extending circumferentially, as illustrated in [Fig. 2] and [Fig. 10]. Each circulation portion 31 is formed by two walls extending circumferentially, along a surface having a general cylindrical or conical shape. An axis of the cylinder or cone is an axis of rotation of the machine. In the example described, the two walls defining a circulation portion 31 form an angle with each other, for example, on the order of 10° to 20°. The two walls defining the circulation portion 31 may have a distance between them, for example, on the order of 3 mm.

[0105] The cooling shell 30 also includes, on either side of the two circulation portions 31, an outer skirt 32 extending substantially cylindrically and an inner skirt 33 extending substantially cylindrically. The outer skirt 32 and the inner skirt 33 are concentric, as illustrated in [Fig. 11].

[0106] As illustrated in [Fig. 2], the circulation portions 31 are intended to be positioned between cooling fins 20, when the cooling shell 30 is placed on the stator with the winding 10. The cooling shell 30 then conforms to the shape of the coil heads 13.

[0107] During the winding manufacturing process 10, electrical conductors 11, in particular manufactured by additive manufacturing, in particular in the shape of an I-pin or a U-pin, are first supplied. Then, a plurality of coil heads 13 connecting the electrical conductors 11 are deposited, in particular by additive manufacturing, on said electrical conductors 11, and then cooling fins 20 are formed, in particular by additive manufacturing, on the coil heads 13 and / or on the side of the stator opposite the coil heads 13.

[0108] The main advantages of the invention are the improvement of the heat dissipation of the winding 10 thanks to the cooling fins 20. The cooling shell 30 ensures good heat transfer and efficient circulation of the cooling fluid.

Claims

Demands

1. Winding (10) for a rotating electrical machine stator (1), comprising winding legs (12) designed to extend into stator slots and a plurality of coil heads (13), a coil head (13) connecting two winding legs (12), the winding comprising one or more cooling fins (20) on at least one coil head (13) of the plurality of coil heads and / or on the side of the stator opposite the coil heads (13).

2. Winding according to the preceding claim, the cooling fins (20), or even the coil heads (13), being manufactured by additive manufacturing.

3. Winding according to any one of the preceding claims, at least one fin (20), or even all of the fins, being configured so as not to be traversed by an electric current when an electric current flows through the winding.

4. Winding according to any one of the preceding claims, at least one fin (20) being disposed on the side of the stator (1) opposite the coil heads.

5. Winding according to any one of the preceding claims, at least one fin (20) being disposed on the top of a coil head.

6. Winding according to the preceding claim, a coil head, or even a majority of coil heads, better each coil head, comprising at least one cooling fin (20), or even two cooling fins, better three cooling fins.

7. Winding according to the preceding claim, the cooling fins (20) of the same coil head extending parallel to each other.

8. Winding according to any one of the preceding claims, comprising a cooling fin disposed at the intersection of a leg (12) and a coil head (13), in particular an overthickness of the leg at the connection between the leg and the coil head.

9. Electrical conductor (11) for a stator (1) of a rotating electrical machine, comprising first and second legs intended to extend into slots in the stator (1) and a coil head connecting the first and second legs, the electrical conductor (11) having one or more cooling fins (20) on the coil head and / or on the side of the stator opposite the coil head.

10. Rotating electric machine stator, comprising a winding according to any one of claims 1 to 8 or one or more electrical conductors (11) according to the preceding claim.

11. Rotating electrical machine comprising a stator (1) according to claim 10.

12. A method for manufacturing a winding according to any one of claims 1 to 8 or an electrical conductor (11) according to claim 9, comprising the following steps: (a) supplying electrical conductors (11), (b) depositing, in particular by additive manufacturing, on said electrical conductors, a plurality of coil heads (13) connecting the electrical conductors, forming one or more cooling fins on at least one coil head and / or on the side of the stator opposite the coil heads.

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