Motor stator assembly and motor

Abstract

The utility model provides a motor stator assembly and a motor. The motor stator assembly comprises an iron core, a first winding and a second winding. A first conductor groove is formed in the outer peripheral portion of the iron core, and a second conductor groove is formed in the inner peripheral portion. A plurality of axial through holes for cooling fluid to flow through are formed in the iron core, and the axial through holes are distributed at intervals in the circumferential direction and located between the first conductor groove and the second conductor groove in the radial direction. The iron core is divided into a first iron core portion and a second iron core portion by a plurality of axial through holes, and the plurality of first axial through holes are located between a first yoke portion of the first iron core portion and a second yoke portion of the second iron core portion. The first conductor groove is provided with a first winding, and the second conductor groove is provided with a second winding. Thus, not only is the cooling capacity of the iron core improved, but also the decoupling effect between the magnetic fields of the radial inner and outer stators of the motor stator assembly is improved, so that the motor relieves or eliminates the problems of torque fluctuation and NVH caused by mutual coupling of the magnetic fields.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electric machines, and in particular to an electric machine stator assembly and an electric machine comprising the same. BACKGROUND

[0002] Nowadays, an electric machine can be used as a motor to output torque and power, and the electric machine can also be used as a generator to charge a battery, so the electric machine can be applied to a power system of a pure electric vehicle or a hybrid electric vehicle. In order to meet the requirements of cost and performance of the vehicle, it is necessary to reduce the cost of the electric machine while improving the power density of the electric machine, and it is also necessary for the electric machine to have a smaller size while keeping the performance unchanged. For this purpose, there is a scheme in the prior art to integrate two sets of stators and rotors together to form an electric machine, so as to meet the above-mentioned various requirements.

[0003] For example, in German patent application DE 10 2022 107 665 A1, an electric machine is disclosed as follows. In the electric machine, one winding is installed at the outer peripheral portion of the core and another winding is installed at the inner peripheral portion of the core, so that two stators are arranged on the same core in a radially stacked manner. However, in this electric machine, the magnetic field generated by the winding on the radially outer side in cooperation with the core and the magnetic field generated by the winding on the radially inner side in cooperation with the core produce coupling phenomena, which will cause fluctuations in the torque output by the electric machine and NVH problems. SUMMARY

[0004] The present application is made in view of the above-mentioned state of the art. One object of the present application is to provide an electric machine stator assembly which can substantially reduce the degree of coupling of the magnetic fields generated by two windings radially stacked on a core with each other.

[0005] Another object of the present application is to provide an electric machine comprising the above-mentioned electric machine stator assembly, which can substantially reduce or eliminate torque fluctuations and NVH problems caused by the coupling of the magnetic fields generated by two windings radially stacked on a core with each other.

[0006] In order to achieve the above-mentioned objects, the present application can adopt the following technical solutions.

[0007] The present application provides an electric machine stator assembly comprising:

[0008] a core, an outer circumferential portion of which is formed with a plurality of first conductor slots and an inner circumferential portion of which is formed with a plurality of second conductor slots, the core being further formed with a plurality of first axial through holes for cooling fluid to flow through, the plurality of first axial through holes being distributed at intervals in a circumferential direction of the motor stator assembly and located between the plurality of first conductor slots and the plurality of second conductor slots in a radial direction of the motor stator assembly, the core being divided into a first core portion and a second core portion by the plurality of first axial through holes, and the plurality of first axial through holes being located between a first yoke portion of the first core portion and a second yoke portion of the second core portion;

[0009] a first winding mounted in the plurality of first conductor slots; and

[0010] a second winding mounted in the plurality of second conductor slots.

[0011] In an alternative, all of the first axial through holes are located at the same radial position, and

[0012] The first yoke portion and the second yoke portion are separated by a separation rate greater than or equal to 40% and less than or equal to 95% by means of the plurality of first axial through holes.

[0013] In another alternative, a mounting member and a positioning member are further included, the core is further formed with a second axial through hole for the mounting member to be inserted through and a third axial through hole for the positioning member to be inserted through, and

[0014] The second axial through hole is arranged to overlap the first axial through hole in the radial direction, and the third axial through hole is arranged to overlap the first axial through hole in the radial direction.

[0015] In another alternative, all of the second axial through holes are located at the same radial position, a portion of the second axial through holes are located radially outward of the first axial through holes, and

[0016] All of the third axial through holes are located at the same radial position, a portion of the third axial through holes are located radially inward of the first axial through holes.

[0017] In another alternative, a first end ring and a second end ring are further included,

[0018] The first end ring is mounted on an axial side surface of the core via the mounting member, the first end ring is formed with a first circumferential groove open towards the core, the first circumferential groove continuously extends in a whole circumference and communicates with the first axial through hole, and

[0019] The second end ring is mounted to the other axial side of the core via the mount, and the second end ring is formed with a second circumferential groove that is open toward the core, the second circumferential groove continuously extends over the entire circumference and communicates with the first axial through hole.

[0020] In another alternative, the first end ring is formed with a first mounting through hole corresponding to the second axial through hole, and the second end ring is formed with a second mounting through hole corresponding to the second axial through hole.

[0021] In another alternative, the mount includes a head portion and a rod portion, the outer diameter of the head portion is larger than the outer diameter of the rod portion, the head portion is pressed against the first end ring and the rod portion is inserted through the corresponding first mounting through hole, the second axial through hole and the second mounting through hole,

[0022] The first circumferential groove includes an inter-hole groove portion between two first mounting through holes adjacent in the circumferential direction and a ring groove portion extending around the outer periphery of the first mounting through hole, the ends of the inter-hole groove portion respectively communicate with different ring groove portions, and the groove width of the end of the inter-hole groove portion gradually decreases during the extension of the inter-hole groove portion toward the corresponding ring groove portion.

[0023] In another alternative, the groove width of the second circumferential groove is the same over the entire circumference, and the second end ring is formed with at least one inlet hole for the cooling fluid to enter.

[0024] In another alternative, the first end ring is formed with a plurality of first injection holes communicating with the first circumferential groove, a part of the plurality of first injection holes is open toward the axial one side end of the first winding, and another part of the plurality of first injection holes is open toward the axial one side end of the second winding; and / or

[0025] The second end ring is formed with a plurality of second injection holes communicating with the second circumferential groove, a part of the plurality of second injection holes is open toward the axial other side end of the first winding, and another part of the plurality of second injection holes is open toward the axial other side end of the second winding.

[0026] The present application also provides an electric machine comprising:

[0027] The electric machine stator assembly of any one of the above technical solutions;

[0028] A first rotor located radially outside the core of the electric machine stator assembly; and

[0029] A second rotor located radially inside the core.

[0030] By adopting the technical solution, the motor stator assembly provided by the application includes an iron core, a first winding and a second winding assembled together. The outer circumferential part of the iron core is formed with a plurality of first conductor grooves and the inner circumferential part is formed with a plurality of second conductor grooves. The iron core is further formed with a plurality of first axial through holes for flowing of a cooling fluid such as oil, the plurality of first axial through holes are distributed at intervals in the circumferential direction and are located between the plurality of first conductor grooves and the plurality of second conductor grooves in the radial direction of the motor stator assembly. In addition, the iron core is divided into a first iron core part and a second iron core part by the plurality of first axial through holes, and the plurality of first axial through holes are located between a first yoke part of the first iron core part and a second yoke part of the second iron core part. The first winding is installed in the plurality of first conductor grooves, and the second winding is installed in the plurality of second conductor grooves.

[0031] Since the first iron core part and the second iron core part of the iron core can be separated by the plurality of first axial through holes for flowing of the cooling fluid, the overall circumferential size of the connection structure between the first iron core part and the second iron core part is small. Thus, not only the cooling capacity of the iron core can be improved, but also the decoupling effect of the magnetic fields of the first stator composed of the first iron core part and the first winding and the second stator composed of the second iron core part and the second winding can be improved.

[0032] In addition, the application further provides a motor including the above motor stator assembly, the motor further including a first rotor located at the radial outer side of the iron core and a second rotor located at the radial inner side of the iron core. Since the magnetic field decoupling effect of the two stators of the motor stator assembly is improved, the motor according to the application substantially alleviates or eliminates the torque fluctuation and NVH problem caused by the magnetic fields coupling with each other. BRIEF DESCRIPTION OF DRAWINGS

[0033] FIG. 1A is a perspective schematic view showing a motor stator assembly according to an embodiment of the application.

[0034] FIG. 1B is an exploded structural schematic view showing the motor stator assembly in FIG. 1A .

[0035] FIG. 1C is a side view schematic view showing the motor stator assembly in FIG. 1A .

[0036] FIG. 1D is a cross-sectional view schematic view showing the motor stator assembly in FIG. 1A , in which the section lines are omitted.

[0037] FIG. 2A is a perspective schematic view showing an iron core of the motor stator assembly in FIG. 1A .

[0038] FIG. 2Bis a side view schematic diagram showing the core in FIG. 2A

[0039] FIG. 3 is a side view schematic diagram showing the first end ring of the motor stator assembly in FIG. 1A

[0040] FIG. 4 is a side view schematic diagram showing the second end ring of the motor stator assembly in FIG. 1A

[0041] BRIEF DESCRIPTION OF DRAWINGS

[0042] 1 core; 1h1 first axial through hole; 1h2 second axial through hole; 1h3 third axial through hole; 11 first core portion; 11c first conductor slot; 111 first yoke portion; 112 first tooth portion; 12 second core portion; 12c second conductor slot; 121 second yoke portion; 122 second tooth portion;

[0043] 2 first winding; 21 first conductor;

[0044] 3 second winding; 31 second conductor;

[0045] 4 mounting member; 41 head portion; 42 stem portion;

[0046] 5 positioning member;

[0047] 6 first end ring; 6c first circumferential slot; 6c1 inter-hole slot portion; 6c2 ring slot portion; 6h1 first mounting through hole; 6h2 first injection hole;

[0048] 7 second end ring; 7c second circumferential slot; 7h1 second mounting through hole; 7h2 second injection hole; 7h3 entry hole;

[0049] A axial direction; R radial direction; C circumferential direction. DETAILED DESCRIPTION

[0050] The exemplary embodiments of the present application will be described hereinafter with reference to the accompanying drawings. It is to be understood that the specific description is only for the purpose of teaching one skilled in the art how to implement the present application, and is not intended to limit the scope of the present application in any way.

[0051] In the present application, unless otherwise specified, "axial direction", "radial direction" and "circumferential direction" respectively refer to the axial direction, the radial direction and the circumferential direction of the motor stator assembly. "Axial one side" refers to the left side in FIG. 1D , "axial other side" refers to the right side in FIG. 1D , "radial outer side" refers to the side away from the center axis of the motor stator assembly along the radial direction, and "radial inner side" refers to the side close to the center axis of the motor stator assembly along the radial direction. ​​​

[0052] A motor stator assembly according to an embodiment of the present application will be described below with reference to the accompanying drawings.

[0053] As shown in FIGS. 1A-1D , a motor stator assembly according to an embodiment of the present application includes a core 1, a first winding 2, a second winding 3, a plurality of mounters 4, a plurality of positioners 5, a first end ring 6 and a second end ring 7 assembled together.

[0054] In the present embodiment, as shown in FIG. 2A and FIG. 2B , the core 1 can be composed of a plurality of silicon steel sheets having the same shape stacked together in the axial direction A. The core 1 as a whole has a main body portion of a cylindrical structure, a plurality of first tooth portions 112 protruding from the main body portion toward the radially outer side, and a plurality of second tooth portions 122 protruding from the main body portion toward the radially inner side, the plurality of first tooth portions 112 being uniformly distributed at intervals in the circumferential direction C. One first conductor slot 11c is defined between every two adjacent first tooth portions 112 in the circumferential direction C, each first conductor slot 11c penetrating the core 1 in the axial direction A and having an opening open toward the radially outer side. The plurality of second tooth portions 122 are uniformly distributed at intervals in the circumferential direction C. One second conductor slot 12c is defined between every two adjacent second tooth portions 122 in the circumferential direction C, each second conductor slot 12c penetrating the core 1 in the axial direction A and having an opening open toward the radially inner side. Thus, the core 1 is formed with the plurality of first conductor slots 11c distributed at intervals in the circumferential direction C at the outer peripheral portion thereof and the plurality of second conductor slots 12c distributed at intervals in the circumferential direction C at the inner peripheral portion thereof.

[0055] Further, as shown in FIG. 1B , FIG. 2A , and FIG. 2BAs shown, the core 1 is also formed with a plurality of axial through-holes which are distributed at intervals in the circumferential direction C and which are located between the plurality of first conductor grooves 11c and the plurality of second conductor grooves 12c in the radial direction R. The plurality of axial through-holes include first axial through-holes 1hl for cooling fluid such as oil to flow therethrough to cool the motor stator assembly, second axial through-holes 1h2 for the mounting member 4 to be inserted therethrough, and third axial through-holes 1h3 for the positioning member 5 to be inserted therethrough. The core 1 is divided by the first axial through-holes 1hl into a first core portion 11 and a second core portion 12 located radially inward of the first core portion 11, whereby the main portion of the core 1 is partitioned by the first axial through-holes 1hl into a first yoke portion 111 and a second yoke portion 121, the first core portion 11 being composed of the first yoke portion 111 and the first tooth portion 112 and the second core portion 12 being composed of the second yoke portion 121 and the second tooth portion 122. The plurality of first axial through-holes 1hl are located between the first yoke portion 111 and the second yoke portion 121 in the radial direction R. The first core portion 11 and the second core portion 12 are connected only by connecting portions which separate the axial through-holes, each such connecting portion being configured to have a small circumferential dimension (it can be considered that each connecting portion is a web having a small circumferential thickness), so that the overall circumferential dimension of the connecting structure between the first core portion 11 and the second core portion 12 is small, that is, it can be considered that the first core portion 11 and the second core portion 12 are sufficiently separated by the first axial through-holes 1hl.

[0056] In the present embodiment, as shown in FIGS. 1A-1D the first winding 2 can be a wire cage winding (also referred to as a squirrel cage winding). The first winding 2 includes a plurality of first conductor portions 21 mounted to the plurality of first conductor grooves 11c and mounting rings located at axial end portions of the first winding 2, the first winding 2 being integrally formed by the hairpin units being connected to each other to form predetermined electrical circuits and by the mounting rings. Thus, in a state in which the first winding 2 is energized, the first stator composed of the first winding 2 and the first core portion 11 is capable of generating a desired magnetic field. In addition, the axial end portions of the first winding 2 including the mounting rings respectively protrude from the core 1 toward the axial directions.

[0057] In the present embodiment, as shown in FIGS. 1A-1D the second winding 3 can be a wire cage winding. The second winding 3 includes a plurality of second conductor portions 31 mounted to the plurality of second conductor grooves 12c and mounting rings located at axial end portions of the second winding 3, the second winding 3 being integrally formed by the hairpin units being connected to each other to form predetermined electrical circuits and by the mounting rings. Thus, in a state in which the second winding 3 is energized, the second stator composed of the second winding 3 and the second core portion 12 is capable of generating a desired magnetic field. In addition, the axial end portions of the second winding 3 including the mounting rings respectively protrude from the core 1 toward the axial directions.

[0058] Further, in the present embodiment, as shown inFIG. 1B 、 FIG. 2A and FIG. 2B As shown in FIG. 1, all the first axial through holes 1h1 are located at the same radial position, and the cross-sectional shape and size of different first axial through holes 1h1 can be the same or different. In addition, the second axial through holes 1h2 for inserting the mounting members 4 are located at the same radial position, and these second axial through holes 1h2 are partially located radially outside the first axial through holes 1h1. The third axial through holes 1h3 for inserting the positioning members 5 are located at the same radial position, and these third axial through holes 1h3 are partially located radially inside the first axial through holes 1h1. Thus, the first axial through holes 1h1 and the second axial through holes 1h2 are arranged in radial R overlapping and not completely staggered, and the first axial through holes 1h1 and the third axial through holes 1h3 are arranged in radial R overlapping and not completely staggered.

[0059] In this way, even if the mounting members 4 are inserted into the second axial through holes 1h2 and the positioning members 5 are inserted into the third axial through holes 1h3, by using the above-mentioned first axial through holes 1h1, the separation rate of the first yoke portion 111 of the first core portion 11 and the second yoke portion 121 of the second core portion 12 is greater than or equal to 40% and less than or equal to 95%, so that the magnetic field of the first stator composed of the first core portion 11 and the first winding 2 and the magnetic field of the second stator composed of the second core portion 12 and the second winding 3 can be further decoupled, thereby improving the decoupling effect between the magnetic fields of the two stators. The above-mentioned "separation rate" has the following meaning. In the cross-section of the core 1 of the motor stator assembly, a circle is made with the intersection point of the center axis of the core 1 and the cross-section as the center and the distance from the center to the geometric center of the first axial through hole 1h1 in the cross-section as the radius, and the circle passes through the geometric centers of all the first axial through holes 1h1; further, on the above-mentioned circle, the ratio of the total circumferential length occupied by all the first axial through holes 1h1 (that is, the circumferential size of the first axial through holes 1h1 separating the core 1 on the circle) to the circumference of the circle is the above-mentioned separation rate. Therefore, since the first yoke portion 111 of the first core portion 11 and the second yoke portion 121 of the second core portion 12 of the core 1 can be separated by a plurality of first axial through holes 1h1, the overall circumferential size of the connecting structure between the first core portion 11 and the second core portion 12 is small. Thus, the decoupling effect between the magnetic fields of the first stator composed of the first core portion 11 and the first winding 2 and the second stator composed of the second core portion 12 and the second winding 3 can be improved.

[0060] In the present embodiment, as shown in FIG. 1, the first axial through holes 1h1 are arranged in a circular pattern, and the second axial through holes 1h2 and the third axial through holes 1h3 are arranged in a circular pattern. FIGS. 1A-1DAs shown, the mounting member 4 can be, for example, a threaded mounting member like a bolt and includes an integrally formed head 41 and a rod 42. The head 41 is located on one axial side of the rod 42, and the outer diameter of the head 41 is larger than the outer diameter of the rod 42. The rod 42 extends linearly from the head 41 along axial direction A toward the other axial side, and the end of the rod 42 on the other axial side may be threaded. By using the threaded engagement of the rod 42 with the motor housing, the motor stator assembly can be mounted to the motor housing. FIG. 1D As shown, after the rod 42 passes through the first end ring 6, the second axial through hole 1h2, and the second end ring 7 to be installed in place, the head 41 presses against one axial side of the first end ring 6 (the axial side where the first circumferential groove 6c is not formed). Further, as... FIGS. 1A-1D As shown, the positioning element 5 can be, for example, an open cylindrical pin. The positioning element 5 is formed as a cylinder with a hollow shape. The positioning element 5 can be inserted through the third axial through hole 1h3 and used for relative positioning of the motor stator assembly and the motor housing.

[0061] In this embodiment, as FIGS. 1B-1D and FIG. 3 As shown, the first end ring 6 is formed into an annular shape that extends continuously along the circumferential direction C. The first end ring 6 is arranged coaxially with the iron core 1 and is mounted on one axial side of the iron core 1 via the mounting member 4. The other axial side of the first end ring 6 has a first circumferential groove 6c that faces the iron core 1. The first circumferential groove 6c extends continuously along the circumference and communicates with all the first axial through holes 1h1. The first end ring 6 has a first mounting through hole 6h1 corresponding to the second axial through hole 1h2. The rod portion 42 of the mounting member 4 is inserted through the corresponding first mounting through hole 6h1 and second axial through hole 1h2. To improve the structural strength of the portion where the head 41 of the mounting member 4 acts on the first end ring 6, the first circumferential groove 6c1 can be formed with the following structure. Specifically, as shown... FIG. 3 As shown, the first circumferential groove 6c includes an inter-hole groove 6c1 and an annular groove 6c2 that are interconnected. The inter-hole groove 6c1 is located between two adjacent first mounting through holes 6h1 in the circumferential direction C. Each annular groove 6c2 extends around the outer periphery of the corresponding first mounting through hole 6h1 and has a very small groove width. The two ends of the inter-hole groove 6c1 are respectively connected to different adjacent annular grooves 6c2. In addition, the groove width at both ends of the inter-hole groove 6c1 gradually decreases as it extends toward the corresponding annular groove 6c2. In this way, the space around the first mounting through hole 6h1 of the first circumferential groove 6c is small, thereby improving the structural strength of the part of the head 41 of the mounting member 4 that acts on the first end ring 6 while the parts of the first circumferential groove 6c1 are interconnected.

[0062] In this embodiment, as FIGS. 1B-1D and FIG. 4As shown, the second end ring 7 is formed in an annular shape continuously extending along the entire circumference C, is arranged coaxially with the core 1, and is mounted to the axially other side surface of the core 1 via the mounting member 4. The axially one side surface of the second end ring 7 is formed with a second circumferential groove 7c open toward the core 1, which continuously extends along the entire circumference and communicates with all the first axial through holes 1h1. The second end ring 7 is formed with a second mounting through hole 7h1 corresponding to the second axial through hole 1h2, and the shaft portion 42 of the mounting member 4 is inserted through the second axial through hole 1h2 and the corresponding second mounting through hole 7h1. The second circumferential groove 7c can have the same groove width during the extension along the entire circumference, and the second end ring 7 is formed with at least one inlet hole 7h3 (one inlet hole 7h3 in this embodiment, and two or more inlet holes 7h3 can be included in other alternatives) for the cooling fluid to enter. In this way, the cooling fluid can enter the second circumferential groove 7c via the inlet hole 7h3 and flow into the first circumferential groove 6c via the first axial through hole 1h2 after filling the second circumferential groove 7c, during which the cooling fluid can effectively cool the first core portion 11 and the second core portion 12.

[0063] It can be understood that the first circumferential groove 6c can be blocked due to the presence of the ring groove portion 6c2 and other portions with smaller groove widths, while the second circumferential groove 7c is basically not subject to such a situation. Therefore, the inlet hole 7h3 is provided on the second end ring 7 and multiple inlet holes 7h3 can be provided, and the cooling fluid can still be supplied to the first circumferential groove 6c via the first axial through hole 1h2 through different parts of the second circumferential groove 7c when the first circumferential groove 6c1 is blocked.

[0064] In this embodiment, as shown in FIG. 1B and FIG. 3 The first end ring 6 is formed with a plurality of first injection holes 6h2 communicating with the first circumferential groove 6c. The first injection holes 6h2 located on the radially outer side are open toward the axially one side end portion of the first winding 2, and the first injection holes 6h2 located on the radially inner side are open toward the axially one side end portion of the second winding 3, so that the cooling fluid in the first circumferential groove 6c can be sprayed toward the axially one side end portion of the first winding 2 and the axially one side end portion of the second winding 3 via the plurality of first injection holes 6h2 to cool the first winding 2 and the second winding 3 by the pressure of the cooling fluid itself. In addition, as shown in FIG. 4As shown, the second end ring 7 is formed with a plurality of second injection holes 7h2 communicating with the second circumferential groove 7c. The second injection holes 7h2 located on the radially outer side open toward the axially other end of the first winding 2, and the second injection holes 7h2 located on the radially inner side open toward the axially other end of the second winding 3, so that the cooling fluid in the second circumferential groove 7c can be sprayed toward the axially other end of the first winding 2 and the axially other end of the second winding 3 via the plurality of second injection holes 7h2 to perform cooling by the pressure of the cooling fluid itself.

[0065] By adopting the above scheme, the motor stator assembly according to an embodiment of the present application integrates the first stator composed of the first winding 2 and the first core portion 11 of the core 1 and the second stator composed of the second winding 3 and the second core portion 12 of the core 1 in a stacked manner in the radial direction R, and the motor stator assembly with such a configuration has a compact overall structure and occupies a small space. Moreover, the circumferential grooves formed by the plurality of first axial through holes 1h1 of the core 1 and the first end ring 6 and the second end ring 7 on the axially two sides of the core 1 not only can cool the core 1 of the motor stator assembly, but also can cool the two end portions of each winding, which is conducive to ensuring the performance of the motor stator assembly. In addition, the plurality of first axial through holes 1h1 can also improve the decoupling effect between the magnetic fields of the two stators.

[0066] The following description includes a motor including the motor stator assembly according to an embodiment of the present application.

[0067] The motor according to an embodiment of the present application includes the motor stator assembly, a first rotor and a second rotor described above. The motor stator assembly, the first rotor and the second rotor can be assembled together in a coaxial manner. The first rotor is located on the radially outer side of the core 1 and spaced apart from the core 1, and the first rotor can rotate relative to the first stator in the magnetic field generated by the first stator. The second rotor is located on the radially inner side of the core 1 and spaced apart from the core 1, and the second rotor can rotate relative to the second stator in the magnetic field generated by the second stator. Since the decoupling effect between the magnetic field generated by the first stator of the motor stator assembly and the magnetic field generated by the second stator of the motor stator assembly can be improved, the motor according to the present application substantially alleviates or eliminates the torque fluctuation and NVH problem caused by the magnetic fields generated by the two stators coupling with each other.

[0068] It should be understood that the above embodiments are only exemplary and are not intended to limit the present application. Those skilled in the art can make various modifications and changes to the above embodiments under the teaching of the present application without departing from the scope of the present application. The technical solutions of the present application are further described below.

[0069] i.It can be understood that the motor of the application can be typically applied to a vehicle, which can be applied not only to a pure electric vehicle but also to a hybrid vehicle. The power system of the pure electric vehicle can be an electric axle drive system, which can further include a transmission mechanism such as a gearbox, and the motor is drivingly coupled with an input shaft of the gearbox to realize bidirectional torque transmission. The power system of the hybrid vehicle can further include an engine, and the motor according to the application can be used in cooperation with the engine to constitute a hybrid power system of the hybrid vehicle.

[0070] ii.It can be understood that the cross-sectional shape of the first axial through hole 1h1, the second axial through hole 1h2 and the third axial through hole 1h3 is not limited in the motor stator assembly of the application. For example, the cross-sectional shape of the first axial through hole 1h1 can be typically circular, elliptical, rectangular, oblong, etc.; the cross-sectional shape of the second axial through hole 1h2 and the third axial through hole 1h3 can be typically circular.

[0071] iii.It can be understood that in the case of adopting the scheme according to the application, the power density of the motor and the structural integration of the motor are improved, and the space occupied by the motor is significantly reduced. Moreover, due to the reduction of the space occupied by the motor, the layout of the corresponding supporting components such as the housing and the bearing can also be more compact.

[0072] iv.It can be understood that in the scheme of the application, the preliminary decoupling between the magnetic field of the first stator and the magnetic field of the second stator can be realized by designing other structures, and such decoupling effect can be further improved by using the first axial through hole 1h1 for the cooling fluid to flow through as described above.

[0073] v.In addition, as explained in the above embodiments, when the scheme of using silicon steel sheets with the shape as shown in FIG. 2B stacked together in the axial direction A to manufacture the core 1 as shown in FIG. 2A Since the silicon steel sheets are made by stamping process, the material utilization rate of the silicon steel sheets can be improved, and the material cost is reduced.

Claims

1. A motor stator assembly, characterized in that, include: The iron core has a plurality of first conductor grooves formed on its outer periphery and a plurality of second conductor grooves formed on its inner periphery. The iron core also has a plurality of first axial through holes for cooling fluid to flow through. The plurality of first axial through holes are spaced apart in the circumferential direction of the motor stator assembly and are located in the radial direction of the motor stator assembly between the plurality of first conductor grooves and the plurality of second conductor grooves. The iron core is divided into a first iron core portion and a second iron core portion by the plurality of first axial through holes, and the plurality of first axial through holes are located between a first yoke portion of the first iron core portion and a second yoke portion of the second iron core portion. A first winding is installed in the plurality of first conductor slots; as well as The second winding is installed in the plurality of second conductor slots.

2. The motor stator assembly according to claim 1, characterized in that, All the first axial through holes are located at the same radial position, and Using the plurality of first axial through holes, the separation ratio between the first yoke and the second yoke is greater than or equal to 40% and less than or equal to 95%.

3. The motor stator assembly according to claim 1, characterized in that, It also includes mounting components and positioning components. The iron core further has a second axial through hole through which the mounting component is inserted and a third axial through hole through which the positioning component is inserted. The second axial through hole overlaps with the first axial through hole in the radial direction, and the third axial through hole overlaps with the first axial through hole in the radial direction.

4. The motor stator assembly according to claim 3, characterized in that, All the second axial through holes are located at the same radial position, and a portion of the second axial through holes is located radially outside the first axial through hole. All of the third axial through holes are located on the same radially outer side, and a portion of the third axial through holes are located on the radially inner side of the first axial through holes.

5. The motor stator assembly according to claim 3 or 4, characterized in that, It also includes a first end ring and a second end ring. The first end ring is mounted to one axial side of the iron core via the mounting member. The first end ring has a first circumferential groove that is open to the iron core. The first circumferential groove extends continuously along the entire circumference and communicates with the first axial through hole. The second end ring is mounted on the other side of the iron core via the mounting member. The second end ring has a second circumferential groove that is open to the iron core. The second circumferential groove extends continuously over the entire circumference and communicates with the first axial through hole.

6. The motor stator assembly according to claim 5, characterized in that, The first end ring has a first mounting through hole corresponding to the second axial through hole, and The second end ring is formed with a second mounting through hole corresponding to the second axial through hole.

7. The motor stator assembly according to claim 6, characterized in that, The mounting component includes a head and a rod, wherein the outer diameter of the head is larger than the outer diameter of the rod, the head presses against the first end ring, and the rod is inserted through the corresponding first mounting through hole, second axial through hole, and second mounting through hole. The first circumferential groove includes an inter-hole groove and an annular groove. The inter-hole groove is located between two adjacent first mounting through holes in the circumferential direction. The annular groove extends around the outer periphery of the first mounting through hole. The two ends of the inter-hole groove are respectively connected to different annular grooves. As the inter-hole groove extends toward the corresponding annular groove, the groove width at the end of the inter-hole groove gradually decreases.

8. The motor stator assembly according to claim 5, characterized in that, The second circumferential groove has the same width over the entire circumference, and the second end ring is formed with at least one inlet hole for the cooling fluid to enter.

9. The motor stator assembly according to claim 5, characterized in that, The first end ring has a plurality of first injection holes communicating with the first circumferential groove. A portion of the plurality of first injection holes are open toward the axial end of the first winding, and another portion of the plurality of first injection holes are open toward the axial end of the second winding; and / or The second end ring is formed with a plurality of second injection holes communicating with the second circumferential groove. A portion of the plurality of second injection holes are open toward the other axial end of the first winding, and another portion of the plurality of second injection holes are open toward the other axial end of the second winding.

10. An electric motor, characterized in that, include: The motor stator assembly according to any one of claims 1 to 9; The first rotor is located radially outside the core of the motor stator assembly; as well as The second rotor is located radially inside the iron core.

Images