Electric machine with cooling feature

Abstract

An electric machine defining a radial direction, a circumferential direction, and an axial direction includes a stator core and a plurality of stoppers. The stator core includes a first end and a second end opposite the first end in an axial direction. The stator core defines a plurality of slots extending from a first end to a second end in an axial direction and a plurality of channels extending from the first end to the second end in the axial direction. Each of the plurality of channels is disposed between adjacent ones of the plurality of grooves in the axial direction. Each of the plurality of stoppers is disposed in one of the plurality of grooves and extends in a circumferential direction through a width of a respective one of the plurality of grooves and extends in an axial direction from a first end to a second end.

Description

Technical Field

[0001] The present invention relates to an electric machine for a gas turbine engine. Background Art

[0002] A typical aircraft propulsion system includes one or more gas turbine engines. For some propulsion systems, the gas turbine engine typically includes a fan and a core arranged in fluid communication with each other. In addition, the core of the gas turbine engine typically includes a compressor section, a combustion section, a turbine section, and an exhaust section in a serial flow order. In operation, air is provided from the fan to the inlet of the compressor section, where one or more axial flow compressors gradually compress the air until the air reaches the combustion section. Fuel is mixed with the compressed air and combusted in the combustion section to provide combustion gases. The combustion gases are directed from the combustion section to the turbine section. The flow of combustion gases through the turbine section drives the turbine section and is then directed through the exhaust section, for example, into the atmosphere.

[0003] Incorporating an electric motor (e.g., a generator) into a propulsion engine to generate electrical power from the mechanical energy generated by the propulsion engine can enhance the capabilities of an aircraft. For example, the electricity generated by the electric motor can be used to operate an accessory propulsion device (e.g., an electric fan, motor, or the like) to supplement the thrust provided by the turbine engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] A full and enabling disclosure of the present disclosure, including the best mode thereof, is set forth to those skilled in the art in the specification which proceeds with reference to the accompanying drawings, in which:

[0005] Figure 1 is a cross-sectional view of an exemplary gas turbine engine including an electric machine.

[0006] Figure 2 Includes cooling components Figure 1 A three-dimensional schematic diagram of the stator of an electric motor of a gas turbine engine.

[0007] Figure 3 yes Figure 2 Schematic diagram of the exploded view of the stator core and sealing components of the stator.

[0008] Figure 4 yes Figure 3 An enlarged schematic diagram of the axial slots of the stator core.

[0009] Figure 5 Schematic diagram of the stator with the housing of the cooling assembly.

[0010] Figure 6 is an enlarged schematic diagram of the stator core, wherein the channels are defined.

[0011] Figure 7Ayes Figure 6 A cross-sectional view of the stator core along the plane defined by line 7-7.

[0012] Figure 7B is a cross-sectional view of another stator core.

[0013] Figure 8 is an enlarged schematic diagram of a stator core with extensions disposed on the outer surface.

[0014] Figure 9 is a cross-sectional view of another exemplary stator core.

[0015] Figure 10 is a perspective view of another exemplary electric machine.

[0016] Figure 11 yes Figure 10 A cross-sectional view of an exemplary electric machine along line 11-11. DETAILED DESCRIPTION

[0017] Reference will now be made in detail to the present embodiments of the present disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. The same or similar designations in the drawings and the description have been used to refer to the same or similar parts of the present disclosure.

[0018] As used herein, the word "exemplary" means "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Furthermore, unless expressly stated otherwise, all embodiments described herein should be considered exemplary.

[0019] The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0020] The present disclosure generally relates to cooling electric machines in gas turbine engines. During operation, electric machines, such as motors and generators, generate and may be exposed to heat. This heat can interfere with the operation of the electric machine, for example by increasing the resistance of the windings and reducing the magnetic field generated by the windings. Thermal management of this heat can improve the efficiency and lifespan of the electric machine.

[0021] Liquid coolant can provide heat transfer via convection, and providing liquid coolant in contact with the windings in the stator removes heat directly from the windings. Filling the stator with liquid coolant and flowing the liquid coolant through the windings increases heat transfer from the windings, improving the efficiency of the motor. By applying seals around the stator core to direct the coolant through slots in the stator core, the total amount of coolant can be reduced while maintaining sufficient heat transfer to cool the windings. Furthermore, this configuration can allow for liquid cooling without the need for a dedicated seal plate located in the rotor gap between the rotor and stator of the motor, which increases the width of the rotor gap and can negatively impact the torque and power density of the motor.

[0022] Referring now to the drawings, wherein like numerals refer to like elements throughout, Figure 1 is a schematic cross-sectional view illustrating a gas turbine engine according to an example embodiment of the present disclosure. In particular, Figure 1 An aviation three-stream turbofan engine is provided, referred to herein as "three-stream engine 100". Figure 1 The three-stream engine 100 can be mounted to an aerospace vehicle (e.g., a fixed-wing aircraft) and can generate thrust for propulsion of the aerospace vehicle. The three-stream engine 100 is a "three-stream engine" because its architecture provides three different streams that generate thrust during operation.

[0023] For reference, the three-stream engine 100 defines an axial direction A, a radial direction R, and a circumferential direction C. Furthermore, the three-stream engine 100 defines an axial centerline or longitudinal axis 112 extending along the axial direction A. Generally, the axial direction A extends parallel to the longitudinal axis 112, the radial direction R extends outward from and inward toward the longitudinal axis 112 in a direction orthogonal to the axial direction A, and the circumferential direction extends three hundred and sixty degrees (360°) about the longitudinal axis 112. The three-stream engine 100 extends between a front end 114 and a rear end 116, e.g., along the axial direction A.

[0024] The three-stream engine 100 includes a core engine 118 and a fan section 150 located upstream thereof. Generally, the core engine 118 includes a compressor section, a combustion section, a turbine section, and an exhaust section in a serial flow order. In particular, as shown in FIG. Figure 1As shown, the core engine 118 includes an engine core 120 and a core cowl 122 annularly surrounding the engine core 120. The engine core 120 and the core cowl 122 define an annular core inlet 124. The core cowl 122 further encloses and supports a booster or low-pressure compressor 126 for pressurizing air entering the core engine 118 through the core inlet 124. A high-pressure, multi-stage, axial-flow compressor 128 receives the pressurized air from the LP compressor 126 and further increases the pressure of the air. The pressurized air flows downstream to the combustor 130, where fuel is injected into the pressurized air flow and ignited to increase the temperature and energy level of the pressurized air.

[0025] The high-energy combustion products flow downstream from the combustor 130 to a high-pressure turbine 132. The high-pressure turbine 132 drives the high-pressure compressor 128 via a first shaft, or high-pressure shaft 136. In this regard, the high-pressure turbine 132 is drivingly coupled to the high-pressure compressor 128. The high-energy combustion products then flow to a low-pressure turbine 134. The low-pressure turbine 134 drives the low-pressure compressor 126, components of the fan section 150, and the electric motor 200 via a second shaft, or low-pressure shaft 138. Specifically, the high-energy combustion products drive the turbine blades 135 of the low-pressure turbine 134. In this regard, the low-pressure turbine 134 is drivingly coupled to the low-pressure compressor 126, components of the fan section 150, and the electric motor 200. The low-pressure shaft 138 is coaxial with the high-pressure shaft 136 in this exemplary embodiment. After driving each turbine 132, 134, the combustion products exit the core engine 118 through a core exhaust nozzle 140 to generate propulsive thrust. Thus, the core engine 118 defines a core flow path or core duct 142 extending between the core inlet 124 and the core exhaust nozzle 140. The core duct 142 is an annular duct positioned generally in the radial direction R inboard of the core cover 122.

[0026] The fan section 150 includes a primary fan 152. Figure 1 In the illustrated embodiment, the primary fan 152 is an open rotor or non-ducted primary fan 152. However, in other embodiments, the primary fan 152 may be ducted, for example, by a fan housing or nacelle circumferentially surrounding the primary fan 152. As shown, the primary fan 152 includes an array of fan blades 154 ( Figure 1 Only one is shown in FIG. 1 ). Fan blades 154 may rotate, for example, about longitudinal axis 112. As described above, primary fan 152 is drivingly coupled to low pressure turbine 134 via LP shaft 138. Primary fan 152 may be directly coupled to LP shaft 138, for example, in a direct drive configuration. Alternatively, as Figure 1 As shown, the primary fan 152 may be coupled to the LP shaft 138 via a reduction gearbox 155 , for example, in an indirect drive or gear drive configuration.

[0027] In addition, fan blades 154 can be arranged equidistantly about longitudinal axis 112. Each fan blade 154 has a root and a tip, and a span defined therebetween. Each fan blade 154 defines a central blade axis 156. For the present embodiment, each fan blade 154 of primary fan 152 can rotate about its respective central blade axis 156, for example, in unison with one another. One or more actuators 158 can be controlled to pitch fan blades 154 about their respective central blade axes 156. However, in other embodiments, each fan blade 154 can be fixed or unable to pitch about its central blade axis 156.

[0028] The fan section 150 also includes a fan guide vane array 160 including fan guide vanes 162 ( Figure 1 For this embodiment, the fan guide vanes 162 are not rotatable about the longitudinal axis 112. Each fan guide vane 162 has a root and a tip, and a span defined therebetween. The fan guide vanes 162 may be configured as follows: Figure 1 164 . The fan guide vanes 162 are shown unshielded, or may be shielded, for example, by an annular shroud spaced outwardly in a radial direction R from the tips of the fan guide vanes 162. Each fan guide vane 162 defines a central blade axis 164. For the present embodiment, each fan guide vane 162 of the fan guide vane array 160 is rotatable about its respective central blade axis 164, for example, in unison with each other. One or more actuators 166 may be controlled to pitch the fan guide vanes 162 about their respective central blade axis 164. However, in other embodiments, each fan guide vane 162 may be fixed or may not be pitchable about its central blade axis 164. The fan guide vanes 162 are mounted to a fan shroud 170.

[0029] The fan shroud 170 annularly surrounds at least a portion of the core shroud 122 and is generally positioned outside the core shroud 122 in the radial direction R. In particular, a downstream section of the fan shroud 170 extends over a forward portion of the core shroud 122 to define a fan flow path or fan duct 172. Incoming air may enter the fan duct 172 through a fan duct inlet 176 and may exit through a fan exhaust nozzle 178 to generate propulsive thrust. The fan duct 172 is an annular duct generally positioned outside the core duct 142 in the radial direction R. The fan shroud 170 and the core shroud 122 are connected together and are supported by a plurality of substantially radially extending, circumferentially spaced struts 174 ( Figure 1 Each of the struts 174 may have an aerodynamic profile to guide air flow therethrough. Other struts besides struts 174 may also be used to connect and support the fan shroud 170 and / or the core shroud 122.

[0030] The three-stream engine 100 further defines or includes an inlet duct 180. The inlet duct 180 extends between the engine inlet 182 and the core inlet 124 / fan duct inlet 176. The engine inlet 182 is generally defined at the forward end of the fan cowl 170 and is positioned between the primary fan 152 and the fan guide vanes 162 of the fan guide vane array 160 in the axial direction A. The inlet duct 180 is an annular duct positioned inside the fan cowl 170 in the radial direction R. Air flowing downstream along the inlet duct 180 is divided (not necessarily evenly) into the core duct 142 and the fan duct 172 by the nose of the splitter 144 of the core cowl 122. In the radial direction R, the inlet duct 180 is wider than the core duct 142. In the radial direction R, the inlet duct 180 is also wider than the fan duct 172.

[0031] As shown, fan section 150 also includes an intermediate fan 190. Intermediate fan 190 includes an array of intermediate fan blades 192 ( Figure 1 (Only one is shown in FIG. 1 ). Intermediate fan blades 192 are rotatable, for example, about longitudinal axis 112. Each intermediate fan blade has a root, a tip, and a span defined therebetween. Intermediate fan 190 is drivingly coupled to low-pressure turbine 134 via LP shaft 138. Intermediate fan blades 192 may be arranged at equal circumferential intervals about longitudinal axis 112.

[0032] Thus, the air flowing through inlet duct 180 passes through intermediate fan blades 192 and is accelerated downstream thereof, particularly at the tips of intermediate fan blades 192. At least a portion of the air accelerated by intermediate fan blades 192 flows into fan duct 172 and is ultimately discharged through fan exhaust nozzle 178 to generate propulsive thrust. Furthermore, at least a portion of the air accelerated by intermediate fan blades 192 flows into core duct 142 and is ultimately discharged through core exhaust nozzle 140 to generate thrust. Typically, intermediate fan 190 is a compression device positioned downstream of engine inlet 182. Intermediate fan 190 is operable to accelerate air entering fan duct 172 or the secondary bypass passage.

[0033] In addition, for the depicted Figure 1 In an embodiment, the three-stream engine 100 includes an electric motor operatively coupled to its rotating components. In this regard, the three-stream engine 100 is an aviation hybrid propulsion machine. In particular, as Figure 1As shown, the three-stream engine 100 includes an electric motor 200 operably coupled to the LP shaft 138. The electric motor 200 includes a rotor 202 and a stator 204. The electric motor 200 may be directly mechanically coupled to the LP shaft 138, or the electric motor 200 may be indirectly mechanically coupled to the LP shaft 138, for example, via a gearbox. Furthermore, although the electric motor 200 is operably coupled to the LP shaft 138 at the rear end of the LP shaft 138, the electric motor 200 may be coupled to the LP shaft 138 at any suitable location, or may be coupled to other rotating components of the three-stream engine 100, such as the HP shaft 136.

[0034] In some embodiments, motor 200 may be an electric motor operable to drive LP shaft 138, for example, during engine power-up. In other embodiments, motor 200 may be a generator operable to convert mechanical energy into electrical energy. Thus, the electrical power generated by motor 200 may be directed to various engine and / or aircraft systems. In some embodiments, motor 200 may be a dual-function motor / generator.

[0035] It will be appreciated that in other exemplary embodiments of the present disclosure, the exemplary electric machine 200 may be positioned at any other location within the three-flow engine 100. For example, in other embodiments, the electric machine 200 may be embedded within the three-flow engine 100, inside the compressor section, outside the working gas flow path in the under-hood area, in the nose cone of the three-flow engine 100, and so forth.

[0036] However, it will be understood that the exemplary three-stream engine 100 is provided as an example only. In other exemplary embodiments, the three-stream engine 100 may have any other configuration. For example, in other exemplary embodiments, the engine core 120 may have any other number and arrangement of shafts, spools, compressors, turbines, etc. In addition, in other exemplary embodiments, the three-stream engine 100 may be selectively configured as a ducted turbofan engine (including an outer nacelle surrounding the primary fan 152 and a portion of the engine core 120); as a direct-drive gas turbine engine (which may not include a reduction gearbox, such as the reduction gearbox 155); as a fixed-pitch gas turbine engine (which may not include a variable-pitch fan, such as the primary fan 152); as a dual-flow gas turbine engine (which may not include the fan duct 172); etc.

[0037] Now refer to Figure 2 , a perspective view of the stator 204 of the motor 200 is shown. In particular, the stator 204 is shown to illustrate each component, which will be explained in further detail below. It will be understood that although the rotor 202 is not shown in FIG. Figure 2 , but the stator 204 is configured to receive the rotor 202 to form the motor 200 .

[0038] The stator 204 of the electric machine 200 includes a stator core 206 that defines an axial direction A1, a radial direction R1, a circumferential direction C1, a plurality of windings 208, and a cooling assembly 210. The cooling assembly 210 includes a sealing member 212, a first housing 214 including a first fluid port 216, a second housing 218 including a second fluid port 220, and a fluid supply 222 containing a coolant fluid 224. The stator core 206 includes a first end 226 and a second end 228 and defines a plurality of axial slots 230 extending from the first end 226 to the second end 228 in the axial direction A1. The cooling assembly 210 provides the coolant fluid 224 to the windings 208 disposed in the axial slots 230 of the stator core 206, flooding the stator 204 with the coolant fluid 224 to cool the electric machine 200.

[0039] As described above, the stator 204 includes a stator core 206. It will be appreciated that the directions R1, A1, and C1 of the stator core 206 are locally defined relative to the stator core 206. However, in the illustrated embodiment, the axial direction A1 is arranged parallel to the axial direction A of the three-stream engine 100. The stator core 206 houses the other components of the stator 204, including a plurality of windings 208 and a cooling assembly 210. The stator 204 defines an axial cavity within which the rotor 202 (not shown) rotates. When the electric machine 200 is operated as a generator, the rotating rotor 202 generates an electric field that induces current to flow through the windings 208. When the electric machine 200 is operated as a motor, the windings 208 and the stator 204 generate an electric field that induces rotational motion of the rotor 202.

[0040] Windings 208 are suitable conductors that allow current to flow to generate an electric field. By way of example, windings 208 may include a plurality of conductors, such as Litz wire conductors or stranded conductors. The specific size and length of the conductors may be determined based on the specific electric field generation requirements of motor 200. Alternatively or additionally, windings 208 may include solid elements, such as hairpin conductors or preformed solid coils. The solid elements may define gaps between adjacent solid elements, which allow coolant fluid 224 to flow through.

[0041] The sealing member 212 of the cooling assembly 210 extends in an axial direction from a first end 226 of the stator core 206 to a second end 228 of the stator core 206 through the plurality of axial slots 230. The plurality of windings 208 extend through the sealing member 212 in the plurality of axial slots 230 such that the sealing member 212 surrounds the plurality of windings 208 within each of the plurality of axial slots 230. The sealing member 212 is formed of a material having fluid-tight properties, such as a polymer.

[0042] The first housing 214 is disposed on the seal member 212 at a first end 226, and the second housing 218 is disposed on the seal member 212 at a second end 228. The first and second housings 214, 218 and the seal 212 form a fluid-tight chamber that encloses the plurality of windings 208 within the plurality of axial slots 230. The first and second housings 214, 218 thus inhibit leakage of the coolant fluid 224 from the electric machine 200. Additional seals (not shown) may be disposed about the first end 226 and the second end 228 and join the first housing 214 and the second housing 218 to form the fluid-tight chamber.

[0043] The fluid supply 222 is in fluid communication with the first fluid port 216 of the first housing 214 and the second fluid port 220 of the second housing 218. The fluid supply 222 provides a coolant fluid 224 to the first fluid port 216 of the first housing 214. The coolant fluid 224 flows through the fluid-tight chamber along the plurality of windings 208 from the first end 226 of the stator core 206 to the second end 228 of the stator core 206. The coolant fluid 224 then flows to the second fluid port 220 of the second housing 218 and returns to the fluid supply 222. Although one first fluid port 216 is shown Figure 2 In the exemplary embodiment, it is understood that the first housing 214 may include two or more ports for communicating the coolant fluid 224 from the fluid supply 222 .

[0044] Now refer to Figure 3 , the stator core 206 and the sealing member 212 are shown in an exploded perspective view. More specifically, the sealing member 212 is shown separated from the first end 226 and the second end 228 of the stator core 206 to illustrate the position of the sealing member 212 relative to the stator core 206.

[0045] The sealing assembly 212 includes a plurality of axial seals 232 and a terminal seal 234. The axial seals 232 extend in the circumferential direction C1 around the first end 226 of the stator core 206. Each of the axial seals 232 includes a slot member 236. Each slot member 236 extends through one of the axial slots 230 from the first end 226 of the stator core 206 to the second end 228 of the stator core 206. In other words, each slot member 236 extends through each of the axial slots 230 to allow the coolant fluid 224 to flow through the axial seals 232 without directly contacting the stator core 206. Thus, the slot members 236 form a fluid-tight barrier that protects the stator core 206. The slot members 236 are typically elongated pieces of fluid-resistant material extending from the first end 226 to the second end 228. A stopper 238 surrounds each slot member 236.

[0046] An end seal 234 is disposed at the second end 228 of the stator core 206 and secures the slot member 236 of each axial seal 232 to the stator core 206. More specifically, the end seal 234 is shaped to form a fluid-tight barrier with the slot member 236, allowing the coolant fluid 224 to flow from the axial slots 230 without directly contacting the stator core 206. The end seal 234 forms a friction fit with the stator core 206, securing the end seal 234 against the second end 228.

[0047] refer to Figure 4 , shows a partial cross-sectional view of the stator core 206 and the seal member 212. More specifically, the second end 228 of the stator core 206 is shown to illustrate the stop 238 in the axial slot 230.

[0048] The seal member 212 includes a plurality of retainers 238. Each retainer 238 surrounds one slot member 236 in each of the plurality of axial slots 230. Each retainer 238 is disposed in one of the axial slots 230, forming a friction fit that wedges the retainer into the stator core 206 and inhibits the retainer from loosening from the stator core 206 when the coolant fluid 224 floods the seal member 212. Each retainer 238 extends across the width W of its corresponding axial slot 230 in the circumferential direction C1. Each retainer 238 extends from the first end 226 to the second end 228 in the axial direction A1. The stator core 206 defines an inner surface 240 in the radial direction R1, and the plurality of retainers 238 are substantially flush with the inner surface 240 of the stator core 206. In other words, the plurality of retainers 238 and the inner surface 240 conform to a generally smooth circular surface. The slot members 236 , end seals 234 , and stops 238 form a sleeve or tubular cover that covers the stator core 206 within each axial slot 230 to inhibit coolant fluid 224 from contacting the stator core 206 or leaking through the inner surface 240 .

[0049] In this manner, it can be appreciated that the inner surface 240, together with the plurality of stops 238, forms the innermost surface of the stator 204, allowing for a desired gap width between the stator 204 and the rotor 202 (see FIG. Figure 1 ), while also allowing for the fluid cooling discussed in this article.

[0050] Now refer to Figure 5 , shows an exploded perspective view of the stator core 206 having the first and second shells 214, 218. More specifically, Figure 5 The windings 208 are shown disposed in the axial slots 230 of the stator core 206 , and first and second housings 214 , 218 are positioned at first and second ends 226 , 228 to cover the windings 208 .

[0051] A first housing 214 is disposed at a first end 226 of the stator core 206, and a second housing 218 is disposed at a second end 228 of the stator core 206. When the first housing 214 and the second housing 218 enclose the windings 208 within the sealing member 212, a coolant fluid 224 floods the stator core 206 to transfer heat from the windings 208. More specifically, the coolant fluid 224 from the fluid supply 222 flows through the first fluid port 216 of the first housing 214, flows through each axial slot 230 around the windings 208, and exits through the second fluid port 220 of the second housing 218. As the coolant fluid 224 flows through the stator core 206, the coolant fluid 224 transfers heat from the windings 208 through convective heat transfer, thereby improving the efficiency of the electric machine 200.

[0052] refer to Figure 6-7B , a schematic diagram of the stator core 206 without the cooling assembly 210 is shown. Figure 6 A partial perspective view of the stator core 206 including windings 208 and retainers is shown. Figure 7A A partial cross-sectional view along plane 7 - 7 is shown illustrating the winding 208 and the stop 238 surrounding the winding 208 within the axial slot 230 . Figure 7B Another partial cross-sectional view is shown illustrating the winding 208 and the stop 238 surrounding the winding 208 in the axial slot 230 .

[0053] The stator core 206 defines a plurality of channels 242 extending from the first end 226 to the second end 228 in the axial direction A1. Each of the plurality of channels 242 is disposed between two adjacent axial slots 230 in the circumferential direction C1. Figure 7A As shown, one of the plurality of channels 242 is disposed between each pair of adjacent axial slots 230, such that each pair of adjacent windings 208 defines a channel 242 therebetween. The channels 242 are fluidly separated from the axial slots 230, such that the coolant fluid 224 flows separately through the channels 242 and through the axial slots 230. Thus, the channels 242 provide cooling directly to portions of the stator core 206 that are heated by adjacent windings 208. The channels 242 are fluidly separated from the first housing 214 ( Figure 2 、 Figure 5 ) is fluidly connected to the first fluid port 216 to provide coolant fluid 224 ( Figure 2 ).

[0054] In addition to the channels 242 between the axial slots 230, the stator core 206 may also include additional channels 242 having different shapes and locations, such as Figure 7BAs shown. The channel 242 may be circular and disposed between adjacent axial slots of a pair of axial slots 230. Alternatively, the channel 242 may be rectangular and disposed between adjacent pairs of axial slots 230. However, the channel 242 may be arcuate and disposed radially outside the axial slots 230. It will be appreciated that the stator core 206 may define channels 242 having specific shapes and locations to provide specific cooling for the windings 208.

[0055] The stopper 238 is disposed inside the winding 208 in the radial direction R1 to define a plurality of stopper channels 244. Each stopper channel 244 extends from the first end 226 of the stator core 206 to the second end 228 of the stator core 206 in the axial direction A1. More specifically, referring to Figure 7A-7B , the stopper channels 244 allow the coolant fluid 224 to flow beneath the windings 208 in the axial slots 230. The stops 238 both inhibit the coolant fluid 224 from leaking from the axial slots 230 while also driving the coolant fluid 224 against the windings 208 through the stopper channels 244. Thus, the channels 242 in the stator core 206 and the stopper channels 244 in the axial slots 230 provide convective cooling of the windings 208 and the stator core 206, thereby improving the operation of the electric machine 200.

[0056] Combine Figure 8 , shows a partial schematic diagram of another embodiment of the stator 204. More specifically, Figure 8 A partial view of the stator 204 is shown focusing on the extension 246 disposed on the outer surface 248 of the stator core 206. It will be appreciated that Figure 8 The portion of the stator 204 not shown includes Figure 6 Parts similar to those described above are shown in .

[0057] The stator 204 includes one or more extensions 246 disposed on an exterior surface 248 of the stator core 206 . Figure 8 While one extension 246 is shown, it will be appreciated that the stator 204 may include multiple extensions 246 disposed circumferentially on an outer surface 248 of the stator core 206. The extensions 246 include multiple bases 250 and rings 252 extending between the bases 250. The bases 250 are secured to the outer surface 248, and the rings 252, together with the outer surface 248, define a plurality of outer channels 254. The rings 252 extend in a circumferential direction C1 and are substantially aligned with the curvature of the outer surface 248.

[0058] When the cooling assembly 210 is attached to the stator core 206, the housings 214, 218 ( Figure 2 、 Figure 5 ) surrounds the extension 246 and the outer channel 254. Figure 6-7BThe stator core 206 includes passages 242 and stopper passages 244 between adjacent axial slots 230. Figure 8 The passages 242 are shown as having a rectangular shape and are disposed between the axial slots 230, but the stator core 206 may include a plurality of channels 242 having a rectangular shape. Figure 7B The additional channels 242 of the shapes and positions shown are, for example, circular channels 242 disposed between the axial grooves 230 or arcuate channels 242 disposed outside the axial grooves 230. The coolant fluid 224 ( Figure 2 ) flows through the outer passage 254, the stopper passage 244, and the passage 242 from the first end 226 of the stator core 206 to the second end 228 of the stator core 206. The outer passage 254 provides additional cooling for the outer surface 248 of the stator core 206, thereby improving the operation of the electric machine 200.

[0059] Now see Figure 9 , another exemplary stator 300 of the motor 200 is shown. Figure 9 A cross-sectional view of a stator core 302 of a stator 300 is shown having windings 208 disposed in axial slots 304 of the stator core 302 . Figure 9 The exemplary stator 300 may be connected with Figure 2-Figure 8 The exemplary stators 204 are configured in substantially the same manner, and therefore, unless otherwise noted, like or similar numbers may refer to like or similar parts.

[0060] The stator core 302 defines a plurality of axial slots 304, wherein one axial slot 304 is Figure 9 As shown, the axial slot 304 accommodates two adjacent windings 208, including a first winding 208A and a second winding 208B. A channel 306 is defined between the first winding 208A and the second winding 208B. The coolant fluid 224 flows in the channel 306 between the windings 208A and 208B to cool the windings 208A and 208B.

[0061] The stator 300 includes an insulator 308 and a retainer 310. The insulator 308 extends around the windings 208 to electrically insulate the windings 208 from the stator core 302. In particular, the retainer 310 defines a retainer channel 312 through which the coolant fluid 224 flows through the axial slots 304. Figure 9 In the exemplary embodiment, the passage 306 and the stopper passage 312 are fluidly connected, allowing for additional fluid movement and convective heat transfer.

[0062] Now refer to Figure 10-11 , another stator 320 of the motor 200 is shown. Figure 10 A perspective view of the stator 320 is shown. Figure 11 A cross-sectional view of the stator 320 along line 11 - 11 is shown.

[0063] The stator 320 includes a stator core 322 defining axial slots 324 therein. The windings 208 are disposed in the axial slots 324. The stator 320 includes a sealing member 326 and a housing 328 that contain the coolant fluid 224 for the windings 208. The housing 328 is fastened to the stator core 322 with fasteners 330, such as bolts, screws, pins, clips, or a combination thereof. The fasteners 330 inhibit leakage of the coolant fluid 224 into the rotor 202, improving cooling of the windings 208 and reducing losses of the coolant fluid 224. Although Figure 10-11 The view of FIG. 3 shows the sealing member 326 and the housing 328 at a first end of the stator core 322 , but it is understood that another housing is secured to the second end of the stator core 322 to secure the coolant in the axial slots 324 .

[0064] Further aspects are provided by the subject matter of the following clauses:

[0065] An electric machine defines a radial direction, a circumferential direction, and an axial direction. The electric machine includes: a stator core including a first end and a second end and defining a plurality of axial slots extending from the first end to the second end in the axial direction; a sealing member extending through the plurality of axial slots in the axial direction from the first end to the second end of the stator core; a plurality of windings extending through the sealing member in the axial direction and disposed in the plurality of axial slots; a first housing disposed on the sealing member at the first end, the first housing including a fluid port; and a second housing disposed on the sealing member at the second end, wherein the first housing, the second housing, and the sealing member encapsulate the plurality of windings within the plurality of axial slots.

[0066] An electric machine as recited in any preceding clause, further comprising a fluid supply in fluid communication with the fluid port of the first housing.

[0067] An electric machine as claimed in any preceding clause, wherein the fluid supply comprises a coolant fluid.

[0068] An electric machine as claimed in any preceding clause, wherein the coolant fluid is provided through each axial slot of the plurality of axial slots.

[0069] An electric machine as claimed in any one of the preceding clauses, wherein the first housing, the second housing and the sealing member form a fluid-tight chamber enclosing the plurality of windings.

[0070] An electric machine as claimed in any preceding clause, wherein the second housing comprises a second fluid port.

[0071] An electric machine as claimed in any one of the preceding clauses, wherein the fluid port of the first housing is in fluid communication with the second fluid port of the second housing via the plurality of axial slots.

[0072] The electric machine according to any of the preceding clauses, wherein the sealing member comprises a plurality of axial seals extending around the stator core in the circumferential direction and a terminal seal provided at the second end of the stator core.

[0073] An electric machine according to any one of the preceding clauses, wherein each of the plurality of axial seals comprises: a groove member extending through one of the plurality of axial grooves; and a stopper extending in the circumferential direction across a width of the one of the plurality of axial grooves.

[0074] The electric machine according to any one of the preceding clauses, wherein the stator core further comprises an inner surface in the radial direction, and the sealing member is flush with the inner surface of the stator core.

[0075] An electric machine as claimed in any preceding clause, wherein the stator core defines a plurality of channels, each channel being disposed between two windings of the plurality of windings.

[0076] A motor having radial, circumferential, and axial directions, comprising: a stator core including a first end and a second end opposite the first end in the axial direction, the stator core defining a plurality of slots and a plurality of channels, the plurality of slots extending from the first end to the second end in the axial direction, the plurality of channels extending from the first end to the second end in the axial direction, each of the plurality of channels being disposed between two adjacent slots in the plurality of slots in the circumferential direction; and a plurality of stoppers, each of the plurality of stoppers being disposed in each of the plurality of slots and extending across a width of a corresponding one of the plurality of slots in the circumferential direction and extending from the first end to the second end in the axial direction.

[0077] An electric machine as claimed in any preceding clause, further comprising a plurality of windings, each winding of the plurality of windings being disposed in one of the plurality of slots.

[0078] The electric machine according to any one of the preceding clauses, wherein each of the plurality of stoppers is provided inside a corresponding one of the plurality of windings provided in the one of the plurality of slots in the radial direction.

[0079] An electric machine according to any of the preceding clauses, wherein, in each of the plurality of slots, a corresponding one of the plurality of stops provided therein and a corresponding one of the plurality of windings provided therein define a stopper channel, the stopper channel extending in the axial direction from the first end of the stator core to the second end of the stator core.

[0080] The electric machine of any of the preceding clauses, further comprising a housing disposed at the first end of the stator core and the second end of the stator core, the housing enclosing the plurality of windings within the plurality of slots.

[0081] An electric machine according to any of the preceding clauses, wherein the stator core defines an inner surface in the radial direction, and the plurality of stoppers are flush with the inner surface of the stator core.

[0082] The electric machine according to any one of the preceding clauses, further comprising an extension portion provided on an outer surface of the stator core in the radial direction, the extension portion and the outer surface of the stator core defining an outer channel.

[0083] An electric machine as recited in any preceding clause, further comprising a fluid port in fluid communication with the plurality of channels.

[0084] An electric machine as claimed in any one of the preceding clauses, wherein the plurality of slots are arranged into a plurality of pairs of slots, each pair of slots comprising a first slot and a second slot, and wherein each channel of the plurality of channels is provided between a respective first slot and a respective second slot in each pair of slots of the plurality of pairs of slots.

[0085] An electric machine as recited in any preceding clause, wherein the plurality of windings comprises at least one of Litz wire conductors, Litz conductors, hairpin conductors, preformed solid coils, or combinations thereof.

[0086] An electric machine as claimed in any preceding clause, wherein the housing is secured to the stator core using one or more fasteners.

[0087] An electric machine as claimed in any one of the preceding clauses, wherein the fastener comprises a bolt, a screw, a pin, a clip or a combination thereof.

[0088] An electric machine as claimed in any preceding clause, wherein the sealing member is formed from a fluid sealing material.

[0089] An electric machine as claimed in any preceding clause, wherein the fluid-tight chamber is configured to inhibit leakage of coolant fluid.

[0090] An electric machine as claimed in any preceding clause, wherein each channel of the plurality of channels has one of a rectangular, circular or arcuate shape.

[0091] An electric machine as claimed in any preceding clause, wherein at least one channel of the plurality of channels is arranged radially outwardly of the winding.

[0092] A gas turbine engine comprising an electric machine according to any of the preceding clauses.

[0093] A gas turbine engine as claimed in any one of the preceding clauses, wherein the gas turbine engine is a three-flow engine.

[0094] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. 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 the other examples include structural elements that do not differ from the text of the claims, or if the other examples include equivalent structural elements with insubstantial differences from the text of the claims, then these other examples are intended to be within the scope of the claims.

Claims

1. An electric motor, wherein the electric motor defines a radial direction, a circumferential direction and an axial direction, wherein: The motor comprises: a stator core including a first end and a second end and defining a plurality of axial slots extending in the axial direction from the first end to the second end; a sealing member extending through the plurality of axial slots in the axial direction from the first end of the stator core to the second end of the stator core; a plurality of windings extending through the sealing member in the axial direction and disposed in the plurality of axial slots; a first housing disposed on the sealing member at the first end, the first housing including a fluid port; and a second housing disposed on the sealing member at the second end, The first housing, the second housing and the sealing member encapsulate the plurality of windings in the plurality of axial slots.

2. The motor according to claim 1, characterized in that Further included is a fluid supply in fluid communication with the fluid port of the first housing.

3. The motor according to claim 2, characterized in that in, The fluid supply includes a coolant fluid.

4. The motor according to claim 3, characterized in that in, The coolant fluid is disposed through each of the plurality of axial slots.

5. The motor according to claim 1, characterized in that in, The first housing, the second housing, and the sealing member form a fluid-tight chamber enclosing the plurality of windings.

6. The motor according to claim 1, characterized in that in, The second housing includes a second fluid port.

7. The motor according to claim 6, characterized in that in, The fluid port of the first housing is in fluid communication with the second fluid port of the second housing via the plurality of axial slots.

8. The motor according to claim 1, characterized in that in, The sealing member includes a plurality of axial seals extending around the stator core in the circumferential direction and a terminal seal provided at the second end of the stator core.

9. The motor according to claim 8, characterized in that in, Each axial seal of the plurality of axial seals comprises: a slot member extending through one of the plurality of axial slots; and A stopper extends in the circumferential direction across a width of the one of the plurality of axial grooves.

10. The motor according to claim 1, characterized in that in, The stator core further includes an inner surface in the radial direction, and the sealing member is flush with the inner surface of the stator core.

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