CN117154984A

CN117154984A - Stator assembly and motor

Info

Publication number: CN117154984A
Application number: CN202311107699.7A
Authority: CN
Inventors: 于吉坤; 师富伟; 张耀; 陈文欣; 燕秀龙; 张鹏程; 王广欢; 张雅风; 王剑
Original assignee: Suzhou Huichuan United Power System Co Ltd
Current assignee: Suzhou Huichuan United Power System Co Ltd
Priority date: 2023-08-30
Filing date: 2023-08-30
Publication date: 2023-12-01

Abstract

The invention discloses a stator assembly and a motor, wherein the stator assembly comprises a stator core and a plurality of stator coils, and a plurality of stator slots extending along the radial direction are arranged on the stator core along the circumferential direction; each stator coil comprises a first coil section, a second coil section and a third coil section, wherein the second coil section is inserted into the stator groove body, the third coil section is provided with a welding surface formed by cutting corners, the welding surface is arranged back to the stator core, and two third coil sections to be connected are connected into a whole at the welding surface through welding; the plurality of stator coils comprise first stator coils, are provided with groove parts which extend along the length direction and penetrate through two ends, can form an inner runner in the stator groove body, can guide cooling liquid for heat exchange, and the groove parts of the third coils are arranged towards the stator core. The stator assembly provided by the invention can improve the cooling effect on the stator winding, and simultaneously effectively reduce the axial height of the stator winding, thereby being beneficial to further miniaturization of the propulsion motor.

Description

Stator assembly and motor

Technical Field

The invention relates to the technical field of motors, in particular to a stator assembly and a motor.

Background

Along with the improvement of the space utilization rate requirement of the new energy automobile, the development trend of the motor, the electric control and the speed reducer is that the new energy automobile is integrated into a three-in-one or even multiple-in-one product, and the new energy automobile has higher requirement on the power density of the motor. In order to achieve the improvement of the power density, the flat wire motor is a development direction of a driving motor for a vehicle in the future, and compared with a round wire motor, the flat wire motor has the advantages of higher slot fullness rate, shorter winding end, higher power density and stronger heat dissipation capability, and is particularly suitable for application requirements of miniaturization and light weight of the driving motor for the vehicle.

In order to further improve the volume competitiveness of the conventional flat wire motor, a rotor oil cooling heat dissipation system is matched with a stator and a rotor, the main oil cooling technology of the current stator side is spray oil cooling, and the oil is guided to the end part of a stator coil through an oil pipe or an oil duct of a stator yoke part to spray the end part of the stator coil, so that the heat of the end part of the stator coil can be directly taken away, but the cooling oil is difficult to contact with the part of the stator coil, which is positioned in a stator groove body, and the part of the stator coil, which is positioned in the stator groove body, cannot be effectively cooled, so that the cooling effect on a stator winding is poor, the reliability of the thermal insulation of the stator winding is influenced, and the further miniaturization of the motor is restricted; meanwhile, in the prior art, after the stator coil is inserted into the stator groove body and twisted, a straight line section is reserved for welding, so that the axial height of the stator winding is large, and the motor is restricted to be further miniaturized.

Disclosure of Invention

The invention mainly aims to provide a stator assembly and a motor, and aims to solve the problems that the cooling effect of a stator winding in the existing stator assembly is poor, the axial height of the stator winding is large, and further the motor is restricted to be further miniaturized.

To achieve the above object, the present invention provides a stator assembly comprising:

the stator core is provided with a plurality of stator grooves arranged along the circumferential direction, each stator groove extends along the radial direction of the stator core, and insulating paper is arranged on the inner wall of each stator groove in a surrounding mode; the method comprises the steps of,

the stator coils comprise a first coil section, a second coil section and a third coil section, the first coil section and the third coil section are respectively positioned at two ends of the stator core, the second coil section is inserted into the stator slot, and a plurality of second coil sections are radially stacked in the same stator slot; the end part of the third coil section is provided with a welding surface formed by cutting corners, the welding surface is arranged opposite to the stator core, and the side edges of the welding surfaces of the two to-be-connected third coil sections are arranged in an abutting mode and are connected into a whole through welding;

the stator coils comprise a first stator coil, groove parts extending along the length direction and penetrating through two ends are arranged on the first stator coil, an inner flow passage is formed between the groove parts of the second coil section and the insulating paper, and the inner flow passage can guide cooling liquid at the end part of the stator core into the stator groove and guide the cooling liquid out after heat exchange; the groove portion of the third coil segment is disposed toward the stator core.

Optionally, the welding surface is a plane or a curved surface.

Optionally, the stator slot body has two slot side walls opposite in the circumferential direction; the notch of the groove portion is disposed toward the groove side wall.

Optionally, the plurality of second coil segments in each of the stator slots have the groove portions partially; in the same stator groove body, the notch directions of two adjacent groove parts are opposite.

Optionally, in each stator slot, at least two second coil sections closest to the inner side of the stator core have the groove portions; in the stator groove bodies, the groove openings of the groove parts of the same layer face the same direction.

Optionally, a plurality of the second coil segments in each of the stator slots all have the groove portions; in different stator grooves, the groove openings of the groove parts of the same layer are consistent in orientation; in the same stator groove body, the notch directions of the two groove parts of the adjacent layers are opposite.

Optionally, a plurality of outer flow channels are arranged at intervals along the circumferential direction on the yoke part of the stator core, and each outer flow channel penetrates through two ends of the stator core.

The invention also proposes an electric machine comprising a stator assembly as described above.

Optionally, the motor further includes a first end cover and a second end cover, the first end cover and the second end cover are respectively disposed at two ends of the stator core, a first airtight chamber is formed between the first end cover and one end of the stator core, and a second airtight chamber is formed between the second end cover and the other end of the stator core; each first coil section and each third coil section are respectively positioned in the first closed chamber and the second closed chamber; the interiors of the first closed chamber and the second closed chamber are filled with the cooling liquid.

Optionally, a plurality of outer flow channels are arranged at intervals along the circumferential direction on the yoke part of the stator core, and each outer flow channel penetrates through two ends of the stator core; the two ends of each outer runner are respectively communicated with the first closed chamber and the second closed chamber, the two ends of each inner runner are respectively communicated with the first closed chamber and the second closed chamber, and the first closed chamber and the second closed chamber are respectively communicated with a first liquid inlet and a first liquid outlet so that a plurality of outer runners and a plurality of inner runners are arranged in parallel.

Optionally, a plurality of outer flow channels are arranged at intervals along the circumferential direction on the yoke part of the stator core, and each outer flow channel penetrates through two ends of the stator core; the first closed chamber is divided into two closed sub-chambers; each first coil section is positioned in one of the closed subchambers, and two ends of each inner runner are respectively communicated with one of the closed subchambers and the second closed subchamber; two ends of each outer runner are respectively communicated with the other closed sub-chamber and the second closed chamber; the two sealing sub-chambers are respectively provided with a second liquid inlet and a second liquid outlet in a penetrating way, so that a plurality of outer flow channels and a plurality of inner flow channels are arranged in series.

In the technical scheme of the invention, the plurality of stator coils comprise a first stator coil, the first stator coil is provided with groove parts which extend along the length direction and penetrate through two ends, an inner runner is formed between the groove parts of the second coil sections and the insulating paper, the inner runner can guide the cooling liquid to directly and effectively cool the second coil sections positioned in the stator groove, the cooling effect on the stator winding is improved, the heat load and the torque density of the motor are further improved, and the further miniaturization of the propulsion motor is facilitated; meanwhile, the third coil section of the stator coil is provided with a welding surface formed by cutting angles, the welding surface is arranged back to the stator core, the side edges of the welding surfaces of the two third coil sections to be connected are in butt joint, and the two third coil sections are connected into a whole through welding, so that the axial height of the stator winding can be effectively reduced, and the further miniaturization of the motor is facilitated; and to first stator coil, the recess portion on it extends along length direction and runs through both ends, and the production and processing of being convenient for makes the recess portion of third coil section is towards stator core can avoid recess portion influences the welded surface that the chamfer formed, guarantee two the area of the solder joint that forms after the third coil section welding, and then guarantee stator winding connects's steadiness, avoid influencing the quality of motor.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of an embodiment of a motor according to the present invention;

FIG. 2 is a first embodiment of a partial enlarged view at A in FIG. 1;

FIG. 3 is a second embodiment of a partial enlarged view at A in FIG. 1;

FIG. 4 is a third embodiment of a partial enlarged view at A in FIG. 1;

FIG. 5 is a schematic diagram illustrating a partial structure of an embodiment of a first stator coil according to the present invention;

fig. 6 is a schematic structural diagram of an embodiment of a stator coil according to the present invention;

fig. 7 is a schematic structural diagram of welding two stator coils according to the present invention;

FIG. 8 is a schematic diagram of an embodiment of two first coil solder joint positions according to the present invention;

FIG. 9 is a schematic diagram of a plurality of outer flow channels and a plurality of inner flow channels in parallel according to the present invention;

FIG. 10 is a schematic diagram of FIG. 9;

FIG. 11 is a schematic diagram of a plurality of outer flow channels and a plurality of inner flow channels in series according to the present invention;

fig. 12 is a schematic diagram of fig. 11.

Reference numerals illustrate:

the achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and rear … …) are included in the embodiments of the present invention, the directional indications are merely used to explain the relative positional relationship, movement conditions, etc. between the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are correspondingly changed.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" as it appears throughout includes three parallel schemes, for example "A and/or B", including the A scheme, or the B scheme, or the scheme where A and B are satisfied simultaneously. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.

In view of this, the invention proposes a stator assembly and a motor, which aim to improve the cooling effect on the stator winding, and simultaneously effectively reduce the axial height of the stator winding, thereby being beneficial to further miniaturization of the propulsion motor.

Fig. 1 is a schematic structural diagram of an embodiment of a motor according to the present invention; FIG. 2 is a first embodiment of a partial enlarged view at A in FIG. 1; FIG. 3 is a second embodiment of a partial enlarged view at A in FIG. 1; FIG. 4 is a third embodiment of a partial enlarged view at A in FIG. 1; FIG. 5 is a schematic diagram illustrating a partial structure of an embodiment of a first stator coil according to the present invention; fig. 6 is a schematic structural diagram of an embodiment of a stator coil according to the present invention; fig. 7 is a schematic structural diagram of welding two stator coils according to the present invention; FIG. 8 is a schematic diagram of two first coil solder joint positions according to an embodiment of the present invention; FIG. 9 is a schematic diagram of a plurality of outer flow channels and a plurality of inner flow channels in parallel according to the present invention; FIG. 10 is a schematic diagram of FIG. 9; FIG. 11 is a schematic diagram of a plurality of outer flow channels and a plurality of inner flow channels in series according to the present invention; fig. 12 is a schematic diagram of fig. 11.

As shown in fig. 1, the motor provided by the invention is an M-phase motor, in this example, m=3, that is, the motor is a three-phase motor, and the motor is composed of a rotor assembly and a circular stator assembly; the rotor assembly comprises a rotor core 1 and a rotating shaft 11, the number of poles of the rotor is 2p, and various rotor magnetic circuit structures can be applied to the stator assembly of the invention, such as a permanent magnet rotor, an asynchronous rotor, an electrically excited rotor and the like.

The stator assembly comprises a stator core 2 and a plurality of stator coils, wherein a plurality of stator slot bodies 21 are uniformly arranged on the stator core 2 at intervals along the circumferential direction, and each stator slot body 21 extends along the radial direction of the stator core 2; the number of the stator slots 21 on the stator core 2 is N, N is a multiple of 3 and is an even number, each stator slot 21 is formed between two adjacent stator teeth 22, the notch is semi-closed, and insulating paper 23 is arranged on the inner wall of each stator slot 21 in a surrounding manner; the stator coils are wound on the stator core 2 to form a stator winding, and multiple layers are stacked in the stator slot 21 along the radial direction, in this embodiment, the stator winding is a three-phase stator winding, and can be connected in parallel into different parallel branch numbers, connected in series into different turns, and connected in star or triangle form between phases of the three-phase stator winding according to the design.

It should be noted that, referring to fig. 4 to 8, each of the stator coils includes a first coil section 241, a second coil section 242 and a third coil section 243, where the first coil section 241 and the third coil section 243 are respectively located at two ends of the stator core 2 and are exposed to the stator core 2, the second coil section 242 is inserted into the stator slot 21, and a plurality of the second coil sections 242 are stacked in the same stator slot 21 in a radial direction; the third coil sections 243 have welding surfaces 244 with cut corners, the welding surfaces 244 are disposed opposite to the stator core 2, and the sides of the welding surfaces 244 of the two third coil sections 243 to be connected are disposed in an abutting manner and are integrally connected by welding; when the stator coil has a U-shaped structure, two second coil sections 242 are parallel to each other, the first coil section 241 connects the two second coil sections 242, the first coil section 241 is located at one end (insertion side, also referred to as crown side) of the stator core 2, two third coil sections 243 are provided corresponding to the two second coil sections 242, the third coil sections 243 are connected to the corresponding second coil sections 242, and the third coil sections 243 are located at the other end (welding side) of the stator core 2;

the plurality of stator coils include a first stator coil 24, the first stator coil 24 is provided with a groove 246 extending along a length direction and penetrating through two ends, an inner runner 26 is formed between the groove 246 of the second coil section 242 and the insulating paper 23, and the inner runner 26 can guide the cooling liquid at the end of the stator core 2 into the stator slot 21 and guide the cooling liquid out after heat exchange; the groove portion 246 of the third coil section 243 is provided toward the stator core 2.

In the technical scheme of the invention, the plurality of stator coils comprise a first stator coil 24, the first stator coil 24 is provided with a groove part 246 extending along the length direction and penetrating through two ends, an inner runner 26 is formed between the groove part 246 of the second coil section 242 and the insulating paper 23, the inner runner 26 can guide the cooling liquid to effectively cool the second coil section 242 positioned in the stator groove body 21 directly, the cooling effect on the stator winding is improved, the heat load and the torque density of the motor are further improved, and the further miniaturization of the propulsion motor is facilitated; meanwhile, the third coil section 243 of the stator coil has a welding surface 244 formed by cutting an angle, the welding surface 244 is disposed opposite to the stator core 2, and the sides of the welding surfaces 244 of the two third coil sections 243 to be connected are disposed in an abutting manner and are integrally connected by welding, so that the axial height of the stator winding can be effectively reduced, and further miniaturization of the motor is facilitated; and to first stator coil 24, recess 246 on it extends along length direction and runs through both ends, and the production and processing of being convenient for makes recess 246 of third coil section 243 is towards stator core 2 can avoid recess 246 influences the welded surface 244 that the chamfer formed, ensure two the area of the solder joint 245 that the third coil section 243 formed after welding, and then guarantee stator winding connects the steadiness, avoid influencing the quality of motor.

It will be appreciated that the stator coil uses insulated conductor wires, alternatively, the middle part of the stator coil is copper conductor, and the outer side of the copper conductor is wrapped with an insulating layer or an enameling or film coating or extrusion molding; the shape of the groove portion 246 is not limited in the present invention, and the shape of the groove portion 246 includes triangle, rectangle, trapezoid, circular arc, etc.; the cooling liquid comprises cooling oil, cooling water and the like, so that a cooling effect can be achieved, and the performance of the stator coil is not affected; the cooling oil in the rotor oil cooling heat dissipation system matched with the stator and the rotor can be directly used.

In some embodiments of the present invention, the welding surface 244 is a plane or a curved surface, so as to ensure the welding quality; further, the welding surface 244 extends in the radial direction of the stator core 2, so that the axial height of the stator winding can be further reduced. In some embodiments, only one groove portion 246 is formed on the first stator coil 24, so that the increase of the heat productivity caused by the too high increase of the resistance value of the stator coil can be avoided, which is not beneficial to ensuring the cooling effect.

In some embodiments of the present invention, referring to fig. 2 to 4, the stator slot 21 has two slot sidewalls opposite to each other in the circumferential direction; the notch of the groove portion 246 is disposed toward the groove side wall. The notch of the stator slot body 21 can be plugged through the second coil section 242 and the insulating paper 23, so that cooling liquid in the stator slot body 21 can be effectively prevented from entering a gap between the stator core 2 and the rotor core 1, and the rotor assembly 1 is prevented from generating extra dragging torque, thereby being beneficial to improving motor efficiency.

In some embodiments of the present invention, referring to fig. 2 to 3, the plurality of second coil segments 242 in each stator slot 21 are provided with the groove 246 partially; in the same stator groove body 21, the notches of two adjacent groove portions 246 are opposite. By this arrangement, the groove 246 of the third coil section 243 faces the stator core 2, so that the stator coil can be connected more easily and stably; meanwhile, the plurality of groove portions 246 in the stator slot body 21 are arranged on two sides, so that the stator winding is cooled more uniformly, and the cooling effect is better.

In some embodiments of the present invention, at least two of the second coil segments 242 closest to the inner side of the stator core 2 have the groove portions 246 in each of the stator slot bodies 21; the notches of the plurality of groove portions 246 of the same layer are aligned in the stator groove body 21. Since the ac loss of the stator coil is larger and the generated heat is also larger as the stator coil is closer to the notch of the stator slot 21, at least two of the second coil sections 242 closest to the inside of the stator core 2 are provided with the groove portions 246 to form the inner flow path 26, and the cooling effect can be effectively ensured.

It will be appreciated that when the plurality of second coil segments 242 in the stator slot body 21 are four layers, two layers closest to the inner side of the stator core 2 use the first stator coil 24 having the groove portions 246, and the other two layers may use the second stator coil 25 having no groove portions 246, or may use the first stator coil 24 having the groove portions 246; when the plurality of second coil segments 242 in the stator slot 21 are six layers, the two layers closest to the inner side of the stator core 2 use the first stator coil 24 having the groove portions 246, the two layers located in the middle may use the second stator coil 25 having no groove portions 246, the first stator coil 24 having the groove portions 246, the two layers located in the outer side may use the second stator coil 25 having no groove portions 246, or the first stator coil 24 having the groove portions 246; and so on.

In some embodiments of the present invention, referring to fig. 4, the plurality of second coil segments 242 in each of the stator slots 21 all have the groove portions 246; in the stator slot 21, the notches of the plurality of groove portions 246 of the same layer are oriented uniformly, and the notches of the plurality of groove portions 246 of the adjacent layer are oriented reversely.

Taking six layers of the second coil sections 242 in the stator slot body 21 as an example, the layers 1, 2, 3, 4, 5 and 6 are sequentially marked from inside to outside along the radial direction of the stator core 2, the stator coils are all U-shaped first stator coils 24, the groove parts 246 of the first stator coils 24 are located at the outer sides, and two second coil sections 242 of the first stator coils 24 are respectively inserted into two adjacent layers of the two stator slot bodies 21 so that the directions of the two groove parts 246 located at the adjacent layers are opposite; in the stator core 2, the slots of all the groove parts 246 of the 1 st layer face the anticlockwise circumferential tangential direction, the slots of all the groove parts 246 of the 2 nd layer face the clockwise circumferential tangential direction, and so on, the 3 rd layer faces the anticlockwise direction, the 4 th layer faces the clockwise direction, the 5 th layer faces the anticlockwise direction, and the 6 th layer faces the clockwise direction; layers 1 to 6 may be clockwise, counterclockwise, clockwise, and counterclockwise in this order.

After the first stator coil 24 is inserted into the two corresponding stator slots 21, the first coil sections 242 may be left on the insertion side of the stator core 2, the two second coil sections 242 are located in the two corresponding layers, the two third coil sections 243 are located on the welding side of the stator core 2, and the two third coil sections 243 of the first stator coil 24 are twisted in opposite directions, so that the third coil sections 243 of the same layer are twisted tangentially along the same circumference, and the third coil sections 243 of adjacent layers are twisted in opposite directions; for example, the layers 6, 4, and 2 are twisted counterclockwise, and the layers 5, 3, and 1 are twisted clockwise, so that the groove portions 246 of the two third coil sections 243 of each of the first stator coils 24 are disposed toward the stator core 2, and the welding surface 244 is disposed opposite to the stator core 2, thereby forming a plurality of the third coil sections 243 arranged in the radial direction; the side edges of the welding surfaces 244 of the two third coil sections to be connected, which are respectively located in the 1 st layer and the 2 nd layer, may be abutted, and welded at the abutting positions of the two welding surfaces 244 by laser welding, and the two third coil sections 243 to be connected, which are respectively located in the 3 rd layer and the 4 th layer, may be welded in the above manner, and the two third coil sections 243 to be connected, which are respectively located in the 5 th layer and the 6 th layer, may be welded. The stator winding is simpler to operate and more stable to connect while improving the cooling effect on the stator winding.

Referring to fig. 8, taking the connection of the two third coil sections 243 located at the 5 th layer and the 6 th layer as an example, a welding manner of the two third coil sections 243 to be connected is specifically described, the ends of the third coil sections 243 form a welding surface 244 by cutting corners, the welding surface 244 is formed on a side surface of the third coil sections 243 opposite to the groove 246 and forms an included angle with the length direction of the third coil sections 243, the welding surface 244 does not interfere with the groove 246, and the area of the welding surface 244 meets the welding requirement; after the third coil sections 243 of the 5 th and 6 th layers are twisted, the groove portions 246 of the two third coil sections 243 to be connected face the stator core 2, the welding surfaces 244 face away from the stator core 2, the welding surfaces 244 of the two third coil sections 243 to be connected are arranged adjacently along the radial direction of the stator core 2, the side edges of the two welding surfaces 244 are abutted, so that the two welding surfaces 244 are basically at the same height, and then the welding is performed at the abutting positions of the two welding surfaces 244 by laser welding, so that the two welding surfaces 244 are welded into a whole, and the welding of the two third coil sections 243 to be connected is realized.

In some embodiments of the present invention, referring to fig. 1, a plurality of outer runners 27 are circumferentially spaced apart from the yoke portion of the stator core 2, and each of the outer runners 27 penetrates through two ends of the stator core 2. The cooling liquid can be led into the outer flow channel 27 and led out after heat exchange to cool the stator core 2, so that the cooling effect is better.

The invention also provides an electric machine, which comprises the stator assembly, wherein the specific structure of the stator assembly is shown in fig. 1 to 8 with reference to the embodiment. It can be understood that, because the motor of the present invention adopts all the technical solutions of all the embodiments, at least the motor has all the beneficial effects brought by the technical solutions of the embodiments, and will not be described in detail herein.

In some embodiments of the present invention, referring to fig. 9 to 12, the motor further includes a first end cover 3 and a second end cover 4, where the first end cover 3 and the second end cover 4 are respectively disposed at two ends of the stator core 2, a first closed chamber 31 is formed between the first end cover 3 and one end of the stator core 2, and a second closed chamber 41 is formed between the second end cover 4 and the other end of the stator core 2; each of the first coil segments 241 and each of the third coil segments 243 are located inside the first closed chamber 31 and the second closed chamber 41, respectively; the interiors of the first closed chamber 31 and the second closed chamber 41 are filled with the cooling liquid.

The cooling liquid in the first closed chamber 31 and the second closed chamber 41 can impregnate and cool the end part of the stator coil, and the cooling liquid enters each inner flow passage 26 and can cool the part of the stator coil positioned in the stator slot body 21; the cooling effect on the stator winding can be improved, meanwhile, the isolation cooling of the stator assembly can be realized, the dragging torque of the rotor assembly is reduced, the motor efficiency, especially the working condition efficiency, is improved, and the continuous voyage mileage of the new energy automobile is improved.

In some embodiments of the present invention, referring to fig. 9 and 10, a plurality of outer runners 27 are circumferentially spaced apart from the yoke portion of the stator core 2, and each outer runner 27 penetrates through two ends of the stator core 2; both ends of each outer flow channel 27 are respectively communicated with the first closed chamber 31 and the second closed chamber 41, both ends of each inner flow channel 26 are respectively communicated with the first closed chamber 31 and the second closed chamber 41, and the first closed chamber 31 and the second closed chamber 41 are respectively communicated with a first liquid inlet 5 and a first liquid outlet 6 so that a plurality of outer flow channels 27 and a plurality of inner flow channels 26 are arranged in parallel.

The flow path of the cooling liquid is as follows: the cooling liquid is introduced into the first closed chamber 31 from the first liquid inlet 5, so as to cool the first coil section 241 of each stator coil, the cooling liquid in the first closed chamber 31 enters into each inner runner 26 and each outer runner 27, then enters into the second closed chamber 41 through each inner runner 26 and each outer runner 27, so as to cool the third coil section 243 of each stator coil, and finally flows out from the first liquid outlet 6, thereby realizing parallel cooling of a plurality of outer runners 27 and a plurality of inner runners 26. It is to be understood that the first liquid inlet 5 may be disposed through the second closed chamber 41, and the first liquid outlet 6 may be disposed through the first closed chamber 31, so that the flow path of the cooling liquid is opposite to the flow path;

the cooling effect can be improved by cooling the stator core 2 and the stator winding simultaneously via the plurality of outer flow passages 27 and the plurality of inner flow passages 26 in parallel; meanwhile, the circulation path of the cooling liquid is shorter, which is beneficial to further improving the cooling effect; moreover, the stator assembly is isolated and cooled, so that the dragging torque of the rotor assembly can be reduced, and the motor efficiency is improved.

In some embodiments of the present invention, referring to fig. 11 to 12, a plurality of outer runners 27 are circumferentially spaced apart from the yoke portion of the stator core 2, and each of the outer runners 27 penetrates through two ends of the stator core 2; the first closed chamber 31 is divided into two closed sub-chambers; each first coil section 241 is located inside one of the closed sub-chambers, and two ends of each inner flow passage 26 are respectively communicated with one of the closed sub-chambers 311 and the second closed sub-chamber; both ends of each outer flow channel 27 are respectively communicated with the other closed subchamber 312 and the second closed chamber 41; the two sealing sub-chambers are respectively provided with a second liquid inlet 7 and a second liquid outlet 8 in a penetrating way, so that a plurality of outer flow passages 27 and a plurality of inner flow passages 26 are arranged in series.

It can be appreciated that the second liquid inlet 7 may be disposed through one of the sealed sub-chambers 311, or may be disposed through the other sealed sub-chamber 312;

when the second liquid inlet 7 is penetrating through one of the sealed sub-chambers 311, and the second liquid outlet 8 is penetrating through the other sealed sub-chamber 312, the flow path of the cooling liquid is as follows: the cooling liquid enters one of the closed sub-chambers 311 from the second liquid inlet 7, can cool the first coil section 241 of each stator coil, the cooling liquid in one of the closed sub-chambers 311 enters each inner flow passage 26, cools the second coil section 242 of the stator coil, then enters the second closed sub-chamber through each inner flow passage 26, can cool the third coil section 243 of each stator coil, enters each outer flow passage 27, enters the other closed sub-chamber 312 through each outer flow passage 27, and finally flows out from the second liquid outlet 8 on the other closed sub-chamber 312, thereby realizing the series cooling of a plurality of outer flow passages 27 and a plurality of inner flow passages 26. When the second liquid inlet 7 is disposed through the other closed sub-chamber 312, and the second liquid outlet 8 is disposed through one of the closed sub-chambers 311, the flow path of the cooling liquid is opposite to the flow path.

The stator core 2 and the stator winding are cooled sequentially via the plurality of outer flow passages 27 and the plurality of inner flow passages 26 in a series manner, so that the cooling effect can be improved; moreover, the stator assembly is isolated and cooled, so that the dragging torque of the rotor assembly can be reduced, and the motor efficiency is improved.

The foregoing description is only of the preferred embodiments of the present invention and is not intended to limit the scope of the invention, and all equivalent structural changes made by the description of the present invention and the accompanying drawings or direct/indirect application in other related technical fields are included in the scope of the invention.

Claims

1. A stator assembly, comprising:

2. The stator assembly of claim 1 wherein the weld face is planar or curved.

3. The stator assembly of claim 1 wherein the stator slot body has two circumferentially opposed slot side walls;

the notch of the groove portion is disposed toward the groove side wall.

4. A stator assembly in accordance with claim 3 wherein a portion of said plurality of said second coil segments within each of said stator slots has said recessed portion;

in the same stator groove body, the notch directions of two adjacent groove parts are opposite.

5. The stator assembly of claim 4 wherein at least two of said second coil segments within each of said stator slots nearest the inside of said stator core have said recessed portions;

in the stator groove bodies, the groove openings of the groove parts of the same layer face the same direction.

6. A stator assembly in accordance with claim 3 wherein a plurality of said second coil segments within each of said stator slots all have said recessed portions;

in different stator grooves, the groove openings of the groove parts of the same layer are consistent in orientation; in the same stator groove body, the notch directions of the two groove parts of the adjacent layers are opposite.

7. The stator assembly of claim 1, wherein the yoke of the stator core is circumferentially spaced apart with a plurality of outer flow passages, each of the outer flow passages extending through both ends of the stator core.

8. An electric machine comprising a stator assembly as claimed in any one of claims 1 to 7.

9. The motor of claim 8, further comprising a first end cap and a second end cap, the first end cap and the second end cap being disposed at two ends of the stator core, respectively, a first closed chamber being formed between the first end cap and one of the ends of the stator core, and a second closed chamber being formed between the second end cap and the other end of the stator core;

each first coil section and each third coil section are respectively positioned in the first closed chamber and the second closed chamber; the interiors of the first closed chamber and the second closed chamber are filled with the cooling liquid.

10. The motor of claim 9, wherein the yoke of the stator core is circumferentially spaced apart with a plurality of outer flow passages, each of the outer flow passages extending through both ends of the stator core;

the two ends of each outer runner are respectively communicated with the first closed chamber and the second closed chamber, the two ends of each inner runner are respectively communicated with the first closed chamber and the second closed chamber, and the first closed chamber and the second closed chamber are respectively communicated with a first liquid inlet and a first liquid outlet so that a plurality of outer runners and a plurality of inner runners are arranged in parallel.

11. The motor of claim 9, wherein the yoke of the stator core is circumferentially spaced apart with a plurality of outer flow passages, each of the outer flow passages extending through both ends of the stator core;

the first closed chamber is divided into two closed sub-chambers; each first coil section is positioned in one of the closed subchambers, and two ends of each inner runner are respectively communicated with one of the closed subchambers and the second closed subchamber; two ends of each outer runner are respectively communicated with the other closed sub-chamber and the second closed chamber; the two sealing sub-chambers are respectively provided with a second liquid inlet and a second liquid outlet in a penetrating way, so that a plurality of outer flow channels and a plurality of inner flow channels are arranged in series.