CN-122001157-A - Axial flux machine and stator for an axial flux machine

Abstract

The invention provides a stator for an axial flux electric machine. The stator includes a plurality of cells disposed generally circumferentially about an axis. Each of the plurality of cells is operable to generate a magnetic field substantially parallel to the axis. Each of the plurality of cells includes an axially extending stator core tooth defining at least a portion of a stator core and a set of windings wound on the stator core tooth. The stator includes a heat sink for facilitating heat dissipation from the stator core during operation of the stator. By facilitating dissipation of heat generated or accumulated in the stator core during operation of the stator, efficiency, and/or longevity of the stator may be improved.

Inventors

• WANG GUIYUN
• CHEN YUTING
• Ruan Guangying

Assignees

• 长庚国际能源股份有限公司

Dates

Publication Date

20260508

Application Date

20251105

Priority Date

20241106

Claims (18)

1. 1. A stator for an axial flux electric machine, comprising: A plurality of cells disposed substantially circumferentially about an axis, each of the plurality of cells being operative to generate a magnetic field substantially parallel to the axis, and each of the plurality of cells respectively comprising: An axially extending stator core tooth defining at least a portion of the stator core, and A set of windings wound around the teeth of the stator core, and A heat sink for facilitating heat dissipation from the stator core during operation of the stator.
2. 2. The stator of claim 1, wherein the heat sink comprises: One or more materials, corresponding to at least one of the plurality of cells, thermally coupled between the stator core and the corresponding set of windings to enable or facilitate thermal conduction between the stator core and the corresponding set of windings.
3. 3. The stator of claim 2, wherein the one or more materials comprise a thermally conductive and electrically insulating material.
4. 4. A stator as claimed in claim 3, the thermally conductive and electrically insulating material comprising a potting material.
5. 5. The stator of claim 2, wherein the one or more materials are configured to be at least partially disposed or filled in a gap between the stator core tooth and the corresponding set of windings.
6. 6. The stator according to claim 5, Wherein the set of windings is provided by wires, and Wherein the one or more materials are further configured to be disposed at least partially in a space between adjacent turns of the wire.
7. 7. The stator of claim 6, wherein a ratio of a width of the space between adjacent turns of the wire to a cross-sectional width of the wire is between about 1:1 and about 2:1, wherein the width of the space and the cross-sectional width are both in a direction parallel to the axis.
8. 8. The stator of any one of claims 2 to 7, wherein the one or more materials are configured such that a portion of the corresponding set of windings is exposed.
9. 9. The stator of any one of claims 2 to 7, wherein each of at least one of the plurality of cells having the one or more materials comprises: an electrically insulating material disposed between the stator core teeth and the one or more materials.
10. 10. The stator according to claim 1 to 7, Wherein at least one of the plurality of units comprises: A first stator core shoe portion disposed at a first axial end of the stator core tooth portion, an A second stator core shoe disposed at a second axial end of the stator core teeth; wherein the first stator core shoe and the second stator core shoe define a portion of the stator core; Wherein the inner surface of the first stator core shoe, the inner surface of the second stator core shoe, and the surface of the stator core tooth together define a channel, an Wherein at least a portion of the inner surface of the first stator core shoe is exposed and/or at least a portion of the inner surface of the second stator core shoe is exposed to provide the heat sink.
11. 11. The stator of claim 10, Wherein the inner surface of the first stator core shoe includes a radially innermost portion defining a radially innermost end and a radially outermost portion defining a radially outermost end; wherein the at least a portion of the inner surface of the first stator core shoe that is exposed includes the radially innermost portion and/or the radially outermost portion, and Wherein the method comprises the steps of The radially innermost end of the first stator core shoe being closer to the axis than a radially innermost end defined by a component received in the channel, and/or The radially outermost end of the first stator core shoe is farther from the axis than a radially outermost end defined by components housed in the channel.
12. 12. The stator of claim 11, Wherein the inner surface of the second stator core shoe includes a radially innermost portion defining a radially innermost end and a radially outermost portion defining a radially outermost end; Wherein the at least a portion of the inner surface of the second stator core shoe that is exposed includes the radially innermost portion and/or the radially outermost portion, and Wherein the method comprises the steps of The radially innermost end of the second stator core shoe is closer to the axis than a radially innermost end defined by the assembly received in the channel, and/or The radially outermost end of the second stator core shoe is farther from the axis than a radially outermost end defined by components housed in the channel.
13. 13. The stator of claim 10, comprising: a stator housing containing the plurality of units and including a first wall including one or more first cavities, each of the one or more first cavities respectively containing the first stator core shoe; Wherein the heat sink includes at least one opening corresponding to each of the one or more first cavities, configured at a location corresponding to the first cavity, to expose at least a portion of an outer surface of the first stator core shoe.
14. 14. The stator of claim 13, the at least one opening corresponding to the first cavity including an opening having substantially the same shape and center as an outer surface of the corresponding first stator core shoe and a size smaller than the outer surface.
15. 15. The stator of claim 13, Wherein the stator housing comprises a second wall comprising one or more second cavities, each of the one or more second cavities respectively accommodating the second stator core shoe, and Wherein the heat sink includes at least one opening corresponding to each of the one or more second cavities, configured at a location corresponding to the second cavity, to expose at least a portion of an outer surface of the second stator core shoe.
16. 16. The stator of claim 15, the at least one opening corresponding to the second cavity including an opening having substantially the same shape and center as an outer surface of the corresponding second stator core shoe and a size smaller than the outer surface.
17. 17. The stator according to claim 1, Wherein each of the plurality of cells comprises: A first stator core shoe portion disposed at a first axial end of the stator core tooth portion, an A second stator core shoe disposed at a second axial end of the stator core teeth; wherein the first stator core shoe and the second stator core shoe define a portion of the stator core; Wherein the stator further includes a stator housing that houses the plurality of units and includes: A first wall including a plurality of first cavities, each of the plurality of first cavities respectively accommodating the first stator core shoe, and A second wall including a plurality of second cavities, each of the plurality of second cavities respectively accommodating the second stator core shoe; wherein for each of the plurality of cells, the heat dissipation device comprises: One or more materials thermally coupled between the stator core and the corresponding set of windings to enable or facilitate thermal conduction between the stator core and the corresponding set of windings; At least a portion of the inner surface of the first stator core shoe that is exposed; At least a portion of the inner surface of the second stator core shoe that is exposed; An opening corresponding to each of the plurality of first cavities, disposed at a location of the corresponding first cavity, to expose a portion of an outer surface of the first stator core shoe, and An opening corresponding to each of the plurality of second cavities is disposed at a location of the corresponding second cavity to expose a portion of an outer surface of the second stator core shoe.
18. 18. An axial flux electric machine, comprising: At least one stator as claimed in any one of claims 1 to 17, and At least one rotor.

Description

Axial flux machine and stator for an axial flux machine Technical Field Embodiments disclosed herein relate to an axial-flux electric machine and a stator for an axial-flux electric machine. Background GB2585357a and GB2619413a disclose some existing axial flux machines. During operation, heat may be generated or accumulated in various components of the axial flux motor (e.g., its stator), for example, due to resistive losses, magnetic losses, stray losses, friction, mechanical losses, and the like. If not properly and timely dissipated, this heat may adversely affect the efficiency, and/or life of the axial-flux motor. Disclosure of Invention In a first aspect, a stator for an axial-flux electric machine is provided. The stator includes a plurality of cells disposed generally circumferentially about an axis. Each of the plurality of cells is operable to generate a magnetic field substantially parallel to the axis. Each of the plurality of cells includes an axially extending stator core tooth defining a portion of a stator core and a set of windings wound on the stator core tooth. The stator comprises heat dissipating means for facilitating heat dissipation from the stator core (at least the stator core teeth) during operation of the stator. By facilitating dissipation of heat generated or accumulated in the stator core (at least the stator core teeth) during operation of the stator, performance, efficiency, and/or lifetime of the stator (and thus the axial-flux motor) may be improved. For example, overheating damage of stator components (e.g., stator housing, adhesive used in the stator) may be reduced. For example, the duration that the axial-flux motor may maintain peak power during operation may be increased. In one embodiment, the heat sink includes one or more materials for at least one of the plurality of cells thermally coupled between the stator core (at least the stator core teeth) and a corresponding set of windings to enable or facilitate thermal conduction (i.e., heat transfer by conduction) between the stator core (at least the stator core teeth) and the corresponding set of windings. The one or more materials may be configured in one or more layers. By enabling or improving heat conduction between the stator core and the corresponding set of windings in at least one of the plurality of cells, heat generated or accumulated in the stator core during operation of the stator may be more quickly and/or more efficiently dissipated. In the example where the stator is non-yoke (i.e., the plurality of stator cores of the plurality of units are not in thermal contact with the yoke and with each other), thermal conduction between the stator cores and the corresponding set of windings may be particularly useful for facilitating heat dissipation from the stator cores. In one embodiment, the heat sink includes one or more materials corresponding to each of the plurality of cells thermally coupled between the stator core (at least the stator core teeth) and a corresponding set of windings to enable or facilitate thermal conduction between the stator core (at least the stator core teeth) and the corresponding set of windings. The one or more materials of the different units may be separate (i.e., not in direct contact with each other). The one or more materials of the different units may be the same (i.e., the same composition) or different (i.e., different compositions). In one embodiment, the one or more materials include a thermally conductive and electrically insulating material. For example, the one or more materials may consist only of the thermally conductive and electrically insulating material. For example, the one or more materials may include at least one other material (in addition to the thermally conductive and electrically insulating material). In one embodiment, the thermally conductive and electrically insulating material comprises a potting material. The potting material may include a potting compound (e.g., an epoxy, with or without additives for improving thermal conductivity). The potting material may not only provide thermal conduction and electrical insulation between the stator core (at least the stator core teeth) and the set of windings, but may also provide improved mechanical strength, improved vibration or impact resistance, improved corrosion protection, and/or improved chemical protection for the stator. In one embodiment, the one or more materials are at least partially disposed (e.g., disposed) in a gap between the stator core teeth and the corresponding set of windings. In one embodiment, the one or more materials fill (substantially completely) the gap. The one or more materials in the gap may provide a more uniform and/or efficient thermal coupling between the stator core teeth (or more generally, the stator core) and the corresponding set of windings. This may be particularly applicable to stators in which the gaps between the stator core teeth and the corresponding set o