Electric motor

Abstract

The present invention relates to an electric machine, and in particular to a stator core, which may define a plurality of core slots in its surface. The core slots may extend between a first end portion and a second end portion of the stator core. A winding may be accommodated in the core slots. The winding may define a channel through at least a portion thereof. A cooling system may be operably coupled to the channel and may be configured to move a cooling fluid through the channel. A turbulator may be positioned within the channel. The turbulator may be located within a flow path of the cooling fluid and may be formed integrally with the winding.

Description

Technical Field

[0001] The present subject matter generally relates to an electric machine having a cooling system fluidly coupled to one or more windings of the electric machine. Background Art

[0002] Electric machines (such as generators, motors, motor / generators, starter / generators, and other electric machines) can be used for a variety of purposes. In operation, an electric machine includes a rotor that can rotate relative to a stator to generate electrical energy and / or can rotate relative to the stator as a result of changing a magnetic field induced in the windings of the stator. During operation of the electric machine, heat is generated that can negatively impact the efficiency or output of the electric machine. Therefore, an electric machine that can dissipate additional heat would be useful. Summary of the Invention

[0003] Aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned by practice of the invention.

[0004] In some embodiments of the present disclosure, an electric machine includes a stator core (sometimes also referred to as a stator iron core) that defines a plurality of core slots in its surface. Windings are received in at least one of the plurality of core slots. The windings define a passageway through at least a portion thereof. A cooling system is operably coupled to the passageway and is configured to move a cooling fluid through the passageway. A turbulator is positioned within the passageway. The turbulator is located within the flow path of the cooling fluid.

[0005] In some embodiments of the present disclosure, the method includes a method of manufacturing an electric machine having a stator core and a rotor, the method including forming windings for the stator core of the electric machine having a passageway defined through at least a portion thereof, wherein forming the windings further includes integrally forming one or more turbulators within the passageway.

[0006] In some embodiments of the present disclosure, a winding for an electric machine includes an elongate body. The elongate body is configured to be operably coupled to at least one of a stator or a rotor. A passageway is defined by the elongate body and extends through at least a portion of the elongate body. A turbulator is positioned within the passageway. The turbulator is located within the flow path of the cooling fluid passing through the passageway.

[0007] With reference to the following description and the appended claims, these and other features, aspects, and advantages of the present invention will become better understood. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0008] Technical Solution 1. An electric machine, comprising:

[0009] A stator core that defines a plurality of core slots in its surface;

[0010] A winding, which is received in at least one of the plurality of core slots, and the winding defines a passage through at least a part thereof;

[0011] A cooling system, which is operably coupled to the passage and configured to move a cooling fluid through the passage; and

[0012] A turbulator, which is positioned within the passage, wherein the turbulator is within the flow path of the cooling fluid.

[0013] Technical solution 2. The electric machine according to any one of the preceding technical solutions, further comprising:

[0014] A controller, which is operably connected to the cooling system and configured to actuate a pump assembly of the cooling system.

[0015] Technical solution 3. The electric machine according to any one of the preceding technical solutions, wherein the turbulator includes a first turbulator separated from a first side portion of the passage by a first distance and a second turbulator separated from an opposite second side portion of the passage by a second distance.

[0016] Technical solution 4. The electric machine according to any one of the preceding technical solutions, wherein the first distance is substantially equal to the second distance.

[0017] Technical solution 5. The electric machine according to any one of the preceding technical solutions, wherein the turbulator is integrally formed with the winding.

[0018] Technical solution 6. The electric machine according to any one of the preceding technical solutions, wherein the turbulator includes a first turbulator having a first width and a second turbulator having a second width.

[0019] Technical solution 7. The electric machine according to any one of the preceding technical solutions, wherein the first width is substantially equal to the second width.

[0020] Technical solution 8. The electric machine according to any one of the preceding technical solutions, wherein the first width is greater than the second width.

[0021] Technical solution 9. The electric machine according to any one of the preceding technical solutions, wherein the turbulator includes a first section extending from an upper portion of the passage and a second section extending from a bottom portion of the passage, and a gap is defined between the first section and the second section.

[0022] Technical solution 10. The electric machine according to any one of the preceding technical solutions, wherein the first section and the second section are vertically offset from each other.

[0023] Technical solution 11. The electric machine according to any of the foregoing technical solutions, wherein the gap defined between the first section and the second section is asymmetric with respect to the center line of the channel.

[0024] Technical solution 12. The electric machine according to any of the foregoing technical solutions, wherein the turbulator includes a first section extending from an upper portion of the channel and a second section extending from a bottom portion of the channel, and a gap is defined between the first section and the second section therebetween.

[0025] Technical solution 13. The electric machine according to any of the foregoing technical solutions, wherein the turbulator includes a plurality of turbulators, and the plurality of turbulators have a first pair of rows arranged on a linear portion of the winding separated by a first length substantially along the direction of the cooling fluid flow path and a second pair of rows arranged on a bent portion of the winding separated by a second length substantially along the direction of the cooling fluid flow path, and the first length and the second length may be substantially equal.

[0026] Technical solution 14. A method of manufacturing an electric machine having a stator core and a rotor, the method comprising:

[0027] Forming a winding having a channel at least partially defined therethrough for the stator core or the rotor of the electric machine, wherein forming the winding further includes integrally forming one or more turbulators within the channel.

[0028] Technical solution 15. The method according to any of the foregoing technical solutions, further comprising:

[0029] Operably coupling the winding to one of the stator core or the rotor; and fluidly coupling a cooling system to the channel, wherein fluidly coupling the cooling system to the channel includes coupling a supply line to an end portion of the winding and coupling a return line to a second end portion of the winding.

[0030] Technical solution 16. The method according to any of the foregoing technical solutions, wherein forming the one or more turbulators within the channel further includes forming at least partially vertically aligned first and second sections of the one or more turbulators, and a gap is defined between the first and second sections of the one or more turbulators.

[0031] Technical solution 17. A winding for an electric machine, comprising:

[0032] An elongate body, wherein the elongate body is configured to be operably coupled to at least one of a stator or a rotor;

[0033] A passageway, defined by the elongated body and extending through at least a portion of the elongated body; and

[0034] A turbulator positioned within the passageway, wherein the turbulator is located within a coolant fluid flow path through the passageway.

[0035] Aspect 18. The winding for an electric machine according to any of the preceding aspects, wherein the passageway is operably coupled to a cooling system configured to move coolant fluid through the passageway.

[0036] Aspect 19. The winding for an electric machine according to any of the preceding aspects, wherein the turbulator includes a first turbulator and an offset second turbulator.

[0037] Aspect 20. The winding for an electric machine according to any of the preceding aspects, wherein each of the first turbulator and the second turbulator includes a first section extending from a first portion of the passageway and a second section extending from a second portion of the passageway, the first portion and the second portion being separated by a gap. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] A complete and enabling disclosure of the invention, including the best mode thereof, for one of ordinary skill in the art, is set forth in the specification, which makes reference to the accompanying drawings, in which:

[0039] Figure 1 is a perspective view of a stator core according to various aspects of the present disclosure;

[0040] Figure 2 is a perspective view of a stator core having a plurality of windings according to various aspects of the present disclosure Figure 1 thereof;

[0041] Figure 3 is a perspective view of a permanent magnet rotor that can be operably coupled to the stator core according to various aspects of the present disclosure;

[0042] Figure 4 is a perspective view of a rotor having one or more windings that can be operably coupled to the stator core according to various aspects of the present disclosure;

[0043] Figure 5 is a perspective view of an electric machine having a rotor positioned within a stator core according to various aspects of the present disclosure;

[0044] Figure 6 is a cross-sectional view of the electric machine taken along line VI-VI Figure 5 thereof;

[0045] Figure 7Schematic diagram of a cooling system operatively coupled to one or more windings of an electric machine according to various aspects of the present disclosure;

[0046] Figure 8A Perspective view of a portion of one of the windings defining a channel according to various aspects of the present disclosure;

[0047] Figure 8B Taken along line VIIIB-VIIIB Figure 8A Cross-sectional view of a portion of the winding;

[0048] Figures 9A - 9D Illustrates various cross-sectional views of the winding taken along line IX-IX according to various aspects of the present disclosure, showing a pair of turbulators separated by various distances; Figure 8A Illustrates various cross-sectional views of the winding taken along line IX-IX according to various aspects of the present disclosure, showing a pair of turbulators separated by various distances;

[0049] Figures 10A - 10D Illustrates various cross-sectional views of the winding taken along line X-X according to various aspects of the present disclosure, showing a pair of turbulators of various widths; Figure 8A Illustrates various cross-sectional views of the winding taken along line X-X according to various aspects of the present disclosure, showing a pair of turbulators of various widths;

[0050] Figures 11A - 11F Illustrates various cross-sectional views of the winding taken along line XI-XI according to various aspects of the present disclosure, showing turbulators of various heights; Figure 8A Illustrates various cross-sectional views of the winding taken along line XI-XI according to various aspects of the present disclosure, showing turbulators of various heights;

[0051] Figure 12A And Figure 12B Illustrates various cross-sectional views of the winding of FIG. 8 taken along line XII-XII according to various aspects of the present disclosure, showing a plurality of turbulators located within the winding;

[0052] Figures 13A - 13C Illustrates various cross-sectional views of the winding of FIG. 8 taken along line XIII-XIII according to various aspects of the present disclosure, showing a plurality of turbulators located within the winding; and

[0053] Figure 14 Flowchart of a method for operating an electric machine according to various aspects of the present disclosure. DETAILED DESCRIPTION

[0054] Reference will now be made in detail to the presently preferred embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Specific details are used in the description to refer to the features in the drawings. The same or similar reference numerals have been used in the drawings and the description to refer to the same or similar parts of the invention.

[0055] As used herein, the terms "first", "second", and "third" may be used interchangeably to distinguish one component from another, and are not intended to indicate the position or importance of the individual components.

[0056] The terms "front" and "rear" refer to relative positions within a gas turbine engine or a vehicle, and to the normal operating posture of the gas turbine engine or the vehicle. For example, with respect to a gas turbine engine, the front refers to a position closer to the engine inlet, and the rear refers to a position closer to the engine nozzle or exhaust section.

[0057] The terms "upstream" and "downstream" refer to relative directions with respect to a coolant flow path in a fluid path. For example, "upstream" refers to the direction from which the coolant flow path originates, and "downstream" refers to the direction to which the coolant flow path leads.

[0058] Unless otherwise specified herein, the terms "coupled", "fixed", "attached to", etc. refer to both direct coupling, fixing, or attachment and indirect coupling, fixing, or attachment through one or more intermediate members or features.

[0059] Unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" include plural references.

[0060] As used throughout the specification and claims herein, approximating language is applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function associated therewith. Accordingly, values modified by terms such as "about", "approximately", "substantially", and "essentially" will not be limited to the exact values specified. In at least some instances, the approximating language may correspond to the precision of the instrument used to measure the value or the precision of the method or machine used to construct or manufacture the component and / or system. For example, the approximating language may refer to being within a 10% limit.

[0061] Herein and throughout the specification and claims, range limitations are combined and interchanged, and such ranges are recognized and include all the subranges contained therein unless the context or language indicates otherwise. For example, all ranges disclosed herein include the endpoints, and the endpoints can be combined independently of each other.

[0062] As used herein, when used in a list of two or more items, the term "and / or" means that any one of the listed items can be taken alone or any combination of two or more of the listed items can be taken. For example, if a composition or component is described as including components A, B, and / or C, the composition or component can include only A; only B; only C; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.

[0063] Generally, the present disclosure provides a conductive winding that can be operably coupled to a stator and / or rotor of an electric machine or any other device incorporating a conductive material. During operation, the rotor can be mechanically powered, driven, or rotated about a rotational axis by a force, such as the mechanical energy of an engine. The relative rotational movement of the rotatable rotor with respect to a fixed or stationary stator generates electrical power in one or more windings due to the interaction of the magnetic fields of the electric machine. The electrical power generated in the one or more windings can be conductively connected to and further delivered to at least one electrical load or power source. In some aspects, the electric machine can provide electrical power to a power distribution system or network. In contrast, when operating as an electric motor, alternating current power, such as three-phase alternating current power, can be provided to one or more windings of the stator, which generates a rotational movement of the rotor.

[0064] The conductive winding can define a channel therein, and one or more turbulators can be positioned within the channel. The one or more turbulators can be configured as any type of structure extending from the inner surface of the channel. In various examples, the turbulators can have a common or varying width, shape, height, and / or offset relative to each other. The turbulators can include pins, recesses, and various other protruding shapes that improve heat transfer by increasing turbulence. The position, size, and frequency of the turbulators are selected to minimize the increase in the loss coefficient due to their presence.

[0065] A cooling system can be operably coupled to the channel and configured to move a cooling fluid through the channel. As the cooling fluid moves through the channel, heat is received from the winding into the cooling fluid, which is then at least partially removed externally from the winding. Additionally, the cooling fluid can contact one or more turbulators located within the channel, which can create less laminar flow within the channel to increase heat transfer from the winding to the cooling fluid and / or increase the surface area of the winding to increase the amount of heat that can be transferred to the cooling fluid. The heated cooling fluid can be cooled by a heat exchanger that can be located externally from the winding.

[0066] The turbulators are configured to improve the thermal performance of an electric machine employing the cooling system. By implementing turbulators inside the winding channels, the heat transfer coefficient (HTC) of the thermal system is increased and thus heat removal from the electric machine is improved. By operating in accordance with one or more of the disclosed aspects, the electric machines provided herein can offer more efficient electric machines due to the reduced operating temperature. The electric machines can additionally or alternatively be capable of generating more electrical power when operating as a generator and / or using electrical power more efficiently when operating as a motor.

[0067] Now referring to the drawings, where like numerals throughout the drawings indicate like elements, Figure 1 and Figure 2A stator core 10 is provided having a generally cylindrical shape, the stator core 10 defining a plurality of core slots 12 formed in a circumferential inner diameter 14 of the stator core 10. The core slots 12 may extend between a first end portion 16 and a second end portion 18 of the stator core 10.

[0068] In various embodiments, the core slots 12 are spaced substantially equally around the circumferential inner diameter 14 of the stator core 10, spaced unequally around the circumferential inner diameter 14 of the stator core 10, and / or combinations thereof. The core slots 12 define a radial depth 20 between the end portions 16, 18 of the core slots 12. The core slots 12 are adapted to receive one or more windings 24. In some embodiments, each winding 24 may have a plurality of segments that may include one or more end link segments 28 and one or more slot segments 26 received in the core slots 12. Without departing from the teachings provided herein, the core slots 12 may have a rectangular cross-sectional shape and / or any other shape as may be seen in Figure 1 and / or any other shape.

[0069] Referring Figures 3 - 6 to, the rotor 30 may include a rotor core 32 and one or more windings 24 and / or magnets 34 supported by the rotor core 32. The rotor 30 may also support a rotatable shaft 40 and / or be operatively coupled to the rotatable shaft 40. In various embodiments, the rotor 30 may be, but is not limited to, a "claw pole" rotor, a permanent magnet non-claw pole rotor, a permanent magnet claw pole rotor, a salient field wound rotor, or an induction type rotor.

[0070] Further referring Figures 3 - 6 to, in some embodiments, the electric machine 38 is formed when the stator 22 and the rotor 30 are operatively coupled. During operation, the rotor 30 may be mechanically powered, driven, or rotated about a rotational axis by a force (such as the mechanical energy of an engine). The relative rotational movement of the rotatable rotor 30 with respect to the fixed or stationary stator 22 generates electrical power in one or more windings 24 due to the interaction of the magnetic fields of the electric machine. The electrical power generated in the one or more windings 24 may be conductively connected to at least one electrical load or power source and further delivered to at least one electrical load or power source. In some aspects, the electric machine 38 may provide electrical power to a power distribution system or power distribution network. In contrast, when operating as an electric motor, alternating current power (such as three-phase alternating current power) may be provided to one or more windings 24 of the stator 22, which produces a rotational movement of the rotor 30. Additionally, the type of electric machine 38 provided herein may be an alternating current (AC) synchronous machine, an AC induction machine, a switched reluctance machine, or any other viable type of electric machine.

[0071] Referring Figures 7 - 8B, in order to maintain the temperature of the electric motor 38 within a desired operating temperature range during normal operation, the electric motor 38 may include a cooling system 42. In some embodiments, one or more of the windings 24 of the electric motor 38 may include an elongate body 86 that defines a cooling passage 44 extending therethrough, and the cooling passage 44 is in fluid communication with the cooling system 42. In some embodiments, each winding 24 may be coupled to the cooling system 42 independently, and / or the first winding 24 may be fluidly coupled to the second winding 24 and serially coupled to the cooling system 42.

[0072] In some embodiments, the cooling system 42 may provide a cooling fluid to the windings 24 of the stator 22 and / or the rotor 30 in the form of a lubricating oil, a consumable liquid (such as water), a gas, a supercritical vapor, and / or any other suitable cooling fluid. In various embodiments, the cooling fluid may have a high specific heat capacity to transfer heat from the windings 24 to the heat exchanger 56 via the cooling fluid flow path FP, may have a low dynamic viscosity to reduce the amount of power required to move the cooling fluid through the cooling system 42 and the passage 44, may have a high flash / boiling temperature to allow for a high operating temperature, and / or have a high dielectric strength to withstand a potential temperature difference across the windings 24 that may generate a corona discharge (which may indent or corrode the windings 24). In various embodiments, the cooling fluid may be electrically insulating to avoid an electrical short circuit through the cooling fluid that causes an axial circulating current (resulting from a potential difference axially across the windings 24) that increases losses, and / or may have a high corrosion resistance to avoid corroding parts of the electric motor 38 contacted by the cooling fluid over time.

[0073] In various embodiments (such as the example illustrated in Figure 7 ), the cooling system 42 may include a cooling system supply line 46 and a return line 48 that are in communication with one or more of the windings 24. The cooling system supply line 46 and the return line 48 transport the cooling fluid 50 to and from the passage 44 of each winding 24. It will be understood that the cooling system supply line 46 and the return line 48 may be formed in a variety of configurations suitable for this purpose.

[0074] The pump assembly 52 (and / or compressor assembly) is positioned between the cooling system supply line 46 and the return line 48 opposite one or more of the windings 24. The pump assembly 52 may be responsible for moving the cooling fluid 50 through the passage 44. In some embodiments, the pump assembly 52 may be configured to maintain the flow rate of the cooling fluid 50 below a maximum desired flow rate, which may reduce and / or prevent erosion of one or more turbulators 54 or any other features that may be located within the passage 44.

[0075] In some examples, the cooling system 42 may include a heat exchanger 56 in communication with both a cooling system supply line 46 and a return line 48. In some examples, the heat exchanger 56 may be positioned between the winding 24 and the pump assembly 52. In some examples, the heat exchanger 56 may be configured to transfer thermal energy from the cooling fluid 50 to the atmosphere, which may reduce the temperature of the cooling fluid 50. Although reference has been made herein to the heat exchanger 56, it should be understood that the present disclosure contemplates the use of any current or future method for transferring thermal energy that will operate as described and claimed.

[0076] In some examples, the flow of the cooling fluid 50 may be considered a closed loop. However, during normal operation, loss of the cooling fluid 50 is anticipated. To this end, the cooling system 42 may further include a reservoir 58 in communication with the return line 48 to replenish any loss of the cooling fluid 50.

[0077] In addition, in some embodiments, the cooling system 42, the stator 22, and / or the electric machine 38 may further include a computing system 60 (or be operably coupled to a computing system 60) that causes the electric machine 38 to perform certain functions, such as actuation of the pump assembly 52. One or more of the functions may be any of the components that control the cooling system 42 and / or the electric machine 38. The computing system 60 may include one or more computing devices 62. The (one or more) computing devices 62 may include one or more processors 64 and one or more memory devices 66. The one or more processors 64 may include any suitable processing device, such as a microprocessor, a microcontroller, an integrated circuit, a logic device, and / or other suitable processing device. The one or more memory devices 66 may include one or more computer-readable media, including but not limited to non-transitory computer-readable media, RAM, ROM, hard disk drives, flash drives, and / or other memory devices.

[0078] One or more memory devices 66 may store information accessible by one or more processors 64, including computer-readable instructions 68 executable by one or more processors 64. The instructions 68 may be any set of instructions that, when executed by one or more processors 64, cause one or more processors 64 to perform operations. In some embodiments, the instructions 68 may be executed by one or more processors 64 to cause one or more processors 64 to perform operations such as any of the operations and functions for which the computing system 60 and / or the computing device(s) 62 are configured, operations for operating the cooling system 42 and / or the motor 38, and / or any other operations or functions of the one or more computing devices 62. The instructions 68 may be software written in any suitable programming language or may be implemented in hardware. Additionally and / or alternatively, the instructions 68 may be executed in logically and / or virtually separate threads on the processor(s) 64. The memory device(s) 66 may further store data 70 accessible by the processor(s) 64. For example, the data 70 may include data indicating motor temperature, winding temperature, cooling fluid temperature, cooling fluid flow rate, efficiency gain based on the use of the cooling system 42, and / or any other information.

[0079] The computing device(s) 62 may further include a network interface 72 for communicating (e.g., via a network) with other components of the system 500, for example. The network interface 72 may include any suitable components for interfacing with one or more networks, including, for example, transmitters, receivers, ports, controllers, antennas, and / or other suitable components. One or more external display devices (not depicted) may be configured to receive one or more commands, data, and / or information from the computing device(s) 62.

[0080] Reference Figures 9A - 9D , in various embodiments, one or more turbulators 54 positioned within the channels may affect the flow of fluid through the channels 44 by changing the pressure; changing the flow rate; changing the flow from laminar to turbulent (or vice versa); increasing the surface area of the channels 44 along the windings 24, thereby improving the heat rejection properties of the windings 24, and so on. Generally, the more turbulent the flow, the greater the heat transfer rate, all other things being equal. In other words, the higher the Reynolds number, the more rapid the heat transfer rate. Additionally, laminar flow of the fluid within the channels 44 may make it more difficult to achieve uniform heat transfer and / or a desired heat transfer rate. Moreover, the turbulators 54 may have a varying concentration along the channels 44 of the windings 24 based on the local heat generation of various portions of the windings 24, which may enhance heat removal from the windings 24 through the cooling system 42 and / or maintain a more uniform temperature along the windings 24.

[0081] One or more channels 44 and / or turbulators 54 located within one or more channels 44 may be formed via an additive manufacturing process. In some embodiments, the turbulators 54 may be formed simultaneously with various portions of the winding 24 during the additive manufacturing process. In some examples, electron beam melting (EBM) may be used to form the winding 24 from a material having high conductivity. For example, the winding 24 may be formed from a material that at least partially includes copper (e.g., 99.95% pure copper). In other examples, the winding 24 may be formed from any other conductive material such as copper alloys, silver, aluminum, aluminum alloys, and / or carbon nanotubes (CNT). Additionally, it will be appreciated that the turbulators 54 may be formed in any manner without departing from the scope of the present disclosure.

[0082] Further referring Figures 9A - 9D , the turbulator 54 may include pins, recesses, and various other protruding shapes that improve heat transfer by increasing turbulence. The location, size, and frequency of the turbulators 54 are selected to minimize the increase in the power loss coefficient due to their presence, thereby creating a higher pressure loss for moving the cooling fluid 50 through the channels 44.

[0083] As Figures 9A - 9D illustrated, each of the turbulators 54 may be aligned along the channel 44 or vary in distance from the side portions of the channel 44 and / or adjacent turbulators 54. For example, as Figure 9A illustrated, a first turbulator and a second turbulator 54 may be positioned a first distance d 1 from each other. In some embodiments, the first distance d 1 may be generally equal to a second distance d 2 defined between the first turbulator 54a and the side portion of the channel 44 and / or a third distance d 3 defined between the second turbulator 54b and the opposite side portion of the channel 44.

[0084] In some embodiments (such as the example illustrated in Figure 9B ), the first turbulator 54a and the second turbulator 54b may be separated by a first distance d 1 , and the first distance d 1 may be generally less than the second distance d 2 respectively defined between the first turbulator 54a and the side portion of the channel 44 and the third distance d 3 respectively defined between the second turbulator 54b and the side portion of the channel 44. Additionally or alternatively, as Figure 9C illustrated, the first distance d 1 may be generally greater than the second distance d 2and a third distance d 3 .

[0085] In some embodiments (such as, Figure 9D the example illustrated in), the second distance d defined between the first turbulator 54a and the side portion of the channel 44 2 may be less than the third distance d defined between the first turbulator 54a and the side portion of the channel 44 3 . As provided herein, the channel 44 may include any number of turbulators 54 along the winding 24. Each of the turbulators 54 may be positioned such that some of the turbulators 54 are similar to Figures 9A - 9D the arrangement illustrated in, while without departing from the scope of the present disclosure, other turbulators 54 may be oriented in any other feasible orientation.

[0086] Referring to Figures 10A - 10D , the turbulator 54 may have any feasible width, and the widths and shapes of the various turbulators 54 may be generally common (e.g., geometrically similar) or vary along the length of the channel 44. For example, the first turbulator 54a and the second turbulator 54b may have: a first width w 1 , which may be between 0.02 millimeters (mm) and 0.6 mm in an embodiment (such as Figure 10A an embodiment illustrated in); a second width w 2 , which may be between 0.3 mm and 0.8 mm in an embodiment (such as Figure 10B an embodiment illustrated in); and / or a third width w 3 , which may be between 0.6 mm and 2 mm in an embodiment (such as Figure 10C an embodiment illustrated in) (or any other feasible width). In some embodiments, the first turbulator 54a may be a fourth width w 5 different from the fifth width w 4 of the second turbulator 54b. In some instances, the fourth width w 4 may be greater than the fifth width w 5 . However, in various embodiments, the fourth width w 4 may be less than the fifth width w 5 . Additionally, the width of each turbulator 54 may be generally consistent and / or vary along the corresponding turbulator 54.

[0087] Referring to Figures 11A - 11F , in various embodiments, the turbulator 54 may extend from the upper portion 76 of the channel 44 and / or the lower portion 78 of the channel 44. In some embodiments (such as Figure 11A an embodiment illustrated in), in Figure 11AOne or more turbulators 54 are provided along winding 24, and the turbulator 54 may continuously extend between an upper portion 76 of the channel 44 and a lower portion 78 of the channel 44.

[0088] It should be noted that, as used herein, the terms "upper" and "lower" as used to describe aspects of the channel 44 merely refer to opposite sides along a direction perpendicular to the flow direction. Unless otherwise stated, the terms upper and lower do not denote any particular orientation or alignment relative to the vertical direction.

[0089] In some embodiments (such as, Figures 11B to 11E those illustrated in ), one or more turbulators 54 along the winding 24 may generally extend from one of an upper portion 76 and a lower portion 78 of the channel 44. In such an embodiment, a first section 80 of the turbulator 54 may extend from the upper portion 76 of the channel 44, and a second section 82 of the turbulator 54 may extend from the bottom portion of the channel 44. In various embodiments, the first section 80 and the second section 82 may be generally vertically aligned, and / or the first section 80 and the second section 82 may be generally vertically offset from each other. As used herein, generally vertically offset means that the extension axis A1 of the first section 80 and the extension axis A2 of the second section 82 are not vertically aligned and / or not parallel.

[0090] Further referring to Figures 11B to 11E , in an example where the turbulator 54 extends less than the entire distance of the channel 44, a gap 84 may be defined between a first section 80 and a second section 82 of the turbulator 54. In various embodiments, the gap 84 has a distance greater than the length of the first section 80 or the second section 82. Additionally, the gaps 84 between various turbulators 54 of the channel 44 may be generally consistent or vary from one turbulator 54 to the next.

[0091] In some instances, the height h of the gap 84 g may be less than 15% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 10% ( t ), may be between 15% and 50% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 25% ( Figure 11B ), may be between 40% and 70% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 50% ( t ), and may be between 70% and 95% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 85% ( Figure 11C ), and may be between 40% and 70% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 50% ( t ), and may be between 70% and 95% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 85% ( Figure 11D ), and may be between 70% and 95% of the total height h between the upper portion 76 and the lower portion 78 of the channel 44 (such as, about 85% ( tbetween 50% and 99.9%, such as, about 75%( Figure 11E ). In various embodiments, the turbulator 54 may extend between side portions of the channel 44 and include the first section 80 and / or the second section 82 provided herein. Additionally, the turbulator 54 may extend along the winding 24 from the top portion, the bottom portion, and / or the side portion in any combination.

[0092] In some embodiments, as Figure 11F illustrated, the turbulator 54 may include only the first section 80 and / or only the second section 82. In such instances, the turbulator 54 may extend from the top portion, the bottom portion, and / or the side portion of the channel 44. Additionally, as generally illustrated in Figure 11F the first section 80 of the turbulator 54 may be longer (or shorter) than the second section 82 of the same turbulator 54. Thus, the gap 84 defined between the first section 80 and the second section 82 is asymmetric with respect to the centerline of the channel 44.

[0093] Referring Figure 12A and Figure 12B , in various portions of the channel 44, the turbulator 54 may be positioned in a staggered orientation as illustrated in Figure 12A and / or in an aligned orientation as illustrated in Figure 12B . Additionally, the turbulator 54 may be solid or hollow (as generally illustrated by the imaginary circles within each turbulator 54 of Figure 12A and Figure 12B ) to minimize the mass of the additional winding 24.

[0094] Each turbulator 54 is positioned within the cooling fluid flow path FP of the channel 44 and is configured to alter the flow of the cooling fluid 50. In instances where the turbulator 54 is positioned in a staggered orientation, as illustrated in Figure 12A , the laterally outermost turbulator 54 of the first row of the turbulator 54 may be positioned a first distance from the side portion of the channel 44, and the laterally outermost turbulator 54 of the second row 90 (which is downstream of the first row 88 of the turbulator 54) may be positioned a second greater distance from the side portion of the channel 44. By incorporating the staggered orientation, the wake effect of the cooling fluid 50 may be reduced and / or prevented within the channel 44. Additionally, the staggered orientation may enhance heat transfer while maintaining or minimizing the pressure increase within the channel 44. It will be appreciated that each row 88, 90 may include any number (one or more) of turbulators 54, and each successive row (e.g., 90) may be positioned downstream of the previous row (e.g., 88). In some instances, some of the turbulators 54 may be staggered while others may be aligned without departing from the scope of the present disclosure.

[0095] Reference Figure 12B , in some embodiments, one or more turbulators 54 in the first row 88 may be in an orientation that is generally aligned with one or more turbulators 54 in a subsequent second row 90. In various embodiments, this alignment may be generally along the cooling fluid flow path FP of the channel 44.

[0096] Reference Figures 13A - 13C , in the non-linear portion of the winding 24, one or more rows 88, 90, 92, 94, 96, 98, 100 of turbulators 54 may be positioned in a common or varying orientation. For example, as Figure 13A illustrated in, the turbulators 54 are aligned in seven rows 88, 90, 92, 94, 96, 98, 100, with one or more turbulators 54 in each row 88, 90, 92, 94, 96, 98, 100. In the illustrated embodiment, the first pair of rows 88, 92 may be located on the linear portion of the winding 24 and include at least one turbulator 54 in each row 88, 92. One or more turbulators 54 may be oriented at a common distance from the side portion of the channel 44 and generally along the cooling fluid flow path FP by a first length l 1 separated. The second pair of rows 96, 100 may be disposed on the curved portion of the winding 24 and include at least one turbulator 54 in each row 96, 100. One or more turbulators 54 of the second pair of rows 96, 100 may be oriented at a common distance from the side portion of the channel 44 and generally along the cooling fluid flow path FP by a second length l 2 separated. As used herein, the "common" distance may be any distance within 10% of the distance between two members. In various embodiments, the first length l 1 and the second length l 2 may be generally equal.

[0097] Reference Figure 13B , in some embodiments, a row (e.g., 92) of turbulators 54 may be located on the transition portion 102 between the linear portion and the curved portion of the channel 44. The row 88 of turbulators 54 may be located upstream and separated from the row 92 of turbulators 54 located on the transition portion 102 by a third length l 3 separated. Similarly, the row 96 of turbulators 54 may be located downstream and separated from the row 92 of turbulators 54 located on the transition portion 102 by a fourth length l 3 separated. The third length l 3 and the fourth length l 4 may be equal and / or vary along various portions of the winding 24 and / or in various embodiments. Additionally, each of the third length l 3 and the fourth length l 4 may be greater than the first length l1 and a second length l 2 。

[0098] Referring Figure 13C , in some examples, the first pair of rows 88, 92 may be positioned in a first portion (such as, a linear portion of the winding 24), and separated by a fifth length l 5 . The second pair of rows 94, 98 may be positioned in a second portion that may be at least partially within a curved portion of the winding 24, and separated by a sixth length l 6 . The fifth length l 5 and the sixth length l 6 may be equal and / or vary along various portions of the winding 24 and / or in various embodiments.

[0099] Now referring Figure 14 , a flowchart of a method 200 for manufacturing an electric machine 38 in accordance with various aspects of the present disclosure is provided. The electric machine 38 manufactured by the disclosed method may be constructed in accordance with one or more of the embodiments described above and depicted in Figures 1 to 13C . Accordingly, in at least some aspects, the electric machine 38 operated by the method 200 may be incorporated into an engine (such as, an aero gas turbine engine), and may include a stator 22 and a rotor 30.

[0100] As depicted, the method 200 includes forming a stator core 10 ( Figure 4 ) and a rotor 30 ( Figure 4 ) at (202). As provided herein, the stator core 10 and the rotor 30 may be formed by any feasible method. Additionally, in various embodiments, the stator may be positioned external and / or internal to the rotor 30.

[0101] At (204), the method includes forming a winding 24 ( Figure 8A ), the winding 24 having a channel 44 defined at least in part therethrough. As provided herein, one or more turbulators 54 are positioned within the channel 44. The turbulators 54 may be configured to: change pressure, change flow rate, change the flow from laminar to turbulent (or vice versa); increase the surface area of the channel 44 along the winding 24, thereby improving the heat dissipation properties of the winding 24, etc.

[0102] As provided herein, the winding 24 may be formed by an additive manufacturing process such that one or more turbulators 54 are integrally formed with portions of the winding 24. In various examples, the additive manufacturing process may allow the method to include forming at least a first section 80 and a second section 82 of the turbulator 54 that are at least partially vertically aligned in step (206). A gap 84 is defined between the first section 80 and the second section 82 of the turbulator 54. When produced in an additive manufacturing process, one of the first section 80 or the second section 82 of the turbulator 54 may be formed before the remaining first section 80 or second section 82 of the turbulator 54.

[0103] In step (208), the method may include operably coupling the winding 24 to the stator core 10 or the rotor 30. Once the winding 24 is coupled to one of the stator core 10 of the rotor 30, in step (210), the method may include fluidly coupling the cooling system 42 to the passage 44. In some instances, in step (212), the method may include fluidly coupling the cooling system 42 to the passage 44, including coupling a supply line 46 to one end portion of the winding 24 and coupling a return line 48 to a second end portion of the winding 24.

[0104] By operating in accordance with one or more of these aspects, Figures 1 - 13C the motor and / or Figure 14 the method 200 provided herein may provide a more efficient motor due to a reduced operating temperature. The motor may thus be capable of generating a greater electrical power when operating as a generator and / or using electrical power more efficiently when operating as a motor.

[0105] Additional aspects of the present disclosure may be provided in the following clauses:

[0106] An electric motor, comprising: a stator core defining a plurality of core slots in its surface; a winding received in at least one of the plurality of core slots, the winding defining a passage through at least a portion thereof; a cooling system operably coupled to the passage and configured to move a cooling fluid through the passage; and a turbulator positioned within the passage, wherein the turbulator is located within a flow path of the cooling fluid.

[0107] The electric motor of one or more of these clauses, further comprising: a controller operably coupled to the cooling system and configured to actuate a pump assembly of the cooling system.

[0108] The electric motor of one or more of these clauses, wherein the turbulator includes a first turbulator separated from a first side portion of the passage by a first distance and a second turbulator separated from an opposite second side portion of the passage by a second distance.

[0109] One or more of these clauses of the electric machine, wherein the first distance is substantially equal to the second distance.

[0110] One or more of these clauses of the electric machine, wherein the turbulator is integrally formed with the winding.

[0111] One or more of these clauses of the electric machine, wherein the turbulator includes a first turbulator having a first width and a second turbulator having a second width.

[0112] One or more of these clauses of the electric machine, wherein the first width is substantially equal to the second width.

[0113] One or more of these clauses of the electric machine, wherein the first width is greater than the second width.

[0114] One or more of these clauses of the electric machine, wherein the turbulator includes a first section extending from an upper portion of the channel and a second section extending from a bottom portion of the channel, wherein the first section and the second section define a gap therebetween.

[0115] One or more of these clauses of the electric machine, wherein the first section and the second section are vertically offset from each other.

[0116] One or more of these clauses of the electric machine, wherein the gap defined between the first section and the second section is asymmetric with respect to the centerline of the channel.

[0117] One or more of these clauses of the electric machine, wherein the turbulator includes a first section extending from an upper portion of the channel and a second section extending from a bottom portion of the channel, wherein the first section and the second section define a gap therebetween.

[0118] One or more of these clauses of the electric machine, wherein the turbulator includes a plurality of turbulators having a first pair of rows arranged on a linear portion of the winding separated by a first length substantially along the direction of the cooling fluid flow path and a second pair of rows arranged on a curved portion of the winding separated by a second length substantially along the direction of the cooling fluid flow path, wherein the first length and the second length may be substantially equal.

[0119] A method of manufacturing an electric machine having a stator core and a rotor, the method comprising: forming a winding for the stator core or the rotor of the electric machine, the winding having a channel defined therethrough at least in part, wherein forming the winding further includes integrally forming one or more turbulators within the channel.

[0120] The method of one or more of these clauses further includes: operably coupling the winding to one of a stator core or a rotor; and fluidly coupling a cooling system to the channel, wherein fluidly coupling the cooling system to the channel includes coupling a supply line to one end portion of the winding and coupling a return line to a second end portion of the winding.

[0121] The method of one or more of these clauses, wherein forming one or more turbulators within the channel further includes forming a first section and a second section of one or more turbulators that are at least partially vertically aligned, wherein a gap is defined between the first section and the second section of the one or more turbulators.

[0122] A winding for an electric machine, comprising: an elongate body, wherein the elongate body is configured to be operably coupled to at least one of a stator or a rotor; a channel defined by the elongate body and extending through at least a portion of the elongate body; and a turbulator positioned within the channel, wherein the turbulator is within a flow path of a cooling fluid passing through the channel.

[0123] The winding for an electric machine of claim 17, wherein the channel is operably coupled to a cooling system configured to move a cooling fluid through the channel.

[0124] The winding for an electric machine of claim 17, wherein the turbulator includes a first turbulator and an offset second turbulator.

[0125] The winding for an electric machine of claim 19, wherein each of the first turbulator and the second turbulator includes a first section extending from a first portion of the channel and a second section extending from a second portion of the channel, the first portion and the second portion being separated by a gap.

[0126] The techniques discussed herein refer to computer-based systems and actions taken by computer-based systems and information sent to and from computer-based systems. Those of ordinary skill in the art will recognize that the inherent flexibility of computer-based systems allows for a wide variety of possible configurations, combinations, and divisions of tasks and functionality among and within components. For example, the processes discussed herein can be implemented using a single computing device or multiple computing devices working in combination. Databases, memories, instructions, and applications can be implemented on a single system or distributed across multiple systems. The distributed components can operate sequentially or in parallel.

[0127] Although the specific features of various embodiments may be shown in some drawings and not in others, this is merely for convenience. In accordance with the principles of this disclosure, any feature of a drawing can be cited and / or claimed in combination with any feature of any other drawing.

[0128] This written description uses examples to disclose the invention (including the best mode), and also enables any person skilled in the art to practice the invention (including making and using any device or system and performing any incorporated method). The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. If such other examples include structural elements that are identical to the literal language of the claims, or if they include equivalent structural elements that are not materially different from the literal language of the claims, then such other examples are intended to be within the scope of the claims.

Claims

1. A motor, comprising: a stator core that defines a plurality of core slots in its surface; a winding that is received in at least one of the plurality of core slots, the winding having a channel that extends through at least a portion of the winding; a cooling system that is operably coupled to the channel and configured to move a cooling fluid through the channel; and a turbulator that is positioned within the channel, wherein the turbulator is within a flow path of the cooling fluid; wherein the turbulator includes a plurality of turbulators having a first pair of rows disposed on a linear portion of the winding and separated by a first length along a cooling fluid flow path direction and a second pair of rows disposed on a bent portion of the winding and separated by a second length along the cooling fluid flow path direction, wherein the first length and the second length are equal.

2. The motor according to claim 1, further comprising: a controller that is operably coupled to the cooling system and configured to actuate a pump assembly of the cooling system.

3. The motor according to claim 1, wherein, the turbulator includes a first turbulator separated from a first side portion of the channel by a first distance and a second turbulator separated from an opposite second side portion of the channel by a second distance.

4. The motor according to claim 3, wherein, the first distance is equal to the second distance.

5. The motor according to claim 3, wherein, the turbulator is integrally formed with the winding.

6. The motor according to claim 1, wherein, the turbulator includes a first turbulator having a first width and a second turbulator having a second width.

7. The motor according to claim 6, wherein, the first width is equal to the second width.

8. The motor according to claim 6, wherein, the first width is greater than the second width.

9. The motor according to claim 1, wherein, the turbulator includes a first section extending from an upper portion of the channel and a second section extending from a bottom portion of the channel, wherein the first section and the second section define a gap therebetween.

10. The motor according to claim 9, wherein, the first section and the second section are vertically offset from each other.

11. The motor according to claim 9, wherein, the gap defined between the first section and the second section is asymmetric with respect to a centerline of the channel.

12. A method of manufacturing a motor having a stator core and a rotor, the method comprising: forming a winding for the stator core or the rotor of the motor, the winding having a channel that extends through at least a portion of the winding, wherein forming the winding further includes integrally forming a turbulator within the channel; wherein the turbulator includes a plurality of turbulators having a first pair of rows disposed on a linear portion of the winding and separated by a first length along a cooling fluid flow path direction and a second pair of rows disposed on a bent portion of the winding and separated by a second length along the cooling fluid flow path direction, wherein the first length and the second length are equal.

13. The method according to claim 12, further comprising: operatively coupling the winding to the stator core or the rotor; and operatively coupling a cooling system fluidly to the passage, wherein operatively coupling the cooling system fluidly to the passage includes coupling a supply line to one end portion of the winding and coupling a return line to a second end portion of the winding.

14. The method according to claim 12, wherein forming the turbulator within the passage further includes forming at least a first section and a second section of the turbulator that are at least partially vertically aligned, with a gap defined between the first and second sections of the turbulator.

15. A winding for an electric machine, comprising: an elongate body, wherein the elongate body is configured to be operatively coupled to at least one of a stator or a rotor; a passage defined by the elongate body and extending through at least a portion of the elongate body; and a turbulator positioned within the passage, wherein the turbulator is positioned within a cooling fluid flow path through the passage; wherein the turbulator includes a plurality of turbulators having a first pair of rows disposed on a linear portion of the winding separated by a first length along a cooling fluid flow path direction and a second pair of rows disposed on a curved portion of the winding separated by a second length along the cooling fluid flow path direction, wherein the first length and the second length are equal.

16. The winding for an electric machine according to claim 15, wherein the passage is operatively coupled to a cooling system configured to move cooling fluid through the passage.

17. The winding for an electric machine according to claim 15, wherein the turbulator includes a first turbulator and an offset second turbulator.

18. The winding for an electric machine according to claim 17, wherein each of the first turbulator and the second turbulator includes a first section extending from a first portion of the passage and a second section extending from a second portion of the passage, the first and second portions being separated by a gap.

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