Slot-cooled stator, motor, and winding fixing method for slot-cooled stator

Abstract

The present application provides a slot-cooled stator, comprising a stator core, a winding, and oil covers. The oil covers cover the portion of the winding protruding from the stator core. In the axial direction, an adhesive for fixing the winding is arranged on the side of inner cavities of the oil covers distant from the stator core, a cooling oil accommodating cavity is defined on the side of the cured adhesive facing the stator core, and the cooling oil accommodating cavity is communicated with a stator slot. The present application further provides a motor, comprising the slot-cooled stator as described above. The present application further provides a winding fixing method for a slot-cooled stator, comprising: providing a stator core and a winding; providing two oil covers, wherein the two oil covers cover the portion of the winding protruding from the stator core; making the axis of the stator core parallel to a vertical line; applying an adhesive to the lower oil cover, and curing the adhesive; inverting a slot-cooled stator so that the positions of the two oil covers are reversed; and applying an adhesive to the lower oil cover, and curing the adhesive.

Description

Slot-cooled stator, motor, and winding fixing method of slot-cooled stator Technical Field

[0001] This application relates to the field of electric motors, and to motors that can be used in, for example, pure electric vehicles or hybrid electric vehicles, and more particularly to slot-cooled stators, motors, and methods for fixing the windings of slot-cooled stators. Background Technology

[0002] In flat wire motors, gaps often exist between the stator slots, insulating paper, and copper conductors in order to install insulating paper and copper conductors in the stator slots of the stator core. These gaps may cause the copper conductors to move within the slots under electromagnetic forces or other external forces, resulting in problems such as wear of the varnish (or insulating paper) on the outside of the copper conductors and abnormal NVH (noise, vibration, and harshness).

[0003] The usual solution is to insert the insulating paper and copper conductor into the stator slot, fill the gap with glue, and then fix the copper conductor to the stator slot after the glue has solidified.

[0004] Oil cooling has advantages in cooling motors because, compared to water cooling, the cooling oil can typically come into direct contact with heat-generating components. Especially in the stator slots, the cooling oil can directly contact the heated copper conductors, carrying away heat and significantly improving the motor's continuous power output, making it a promising technology for high-performance vehicles.

[0005] In motor stators cooled by slot cooling oil, gaps need to be maintained between copper conductors or between copper conductors and stator slots to form oil channels. Injecting adhesive into the slots will block these gaps, thus blocking the oil channels. Furthermore, adhesive has good fluidity before solidification, making it difficult to prevent seepage into the oil channels from the assembly gaps when applied to the stator slots, even with protection of the oil channels within the stator slots. Therefore, fixing the copper conductors in slot-cooled stators presents a technical challenge.

[0006] US20120049697A1 and US20160359385A1 disclose a structure that uses a spring to fix a copper conductor in a stator slot, which can fix the copper conductor in a slot-cooled stator. After the spring is inserted into the stator slot, the spring is compressed and undergoes elastic deformation, thereby fixing the copper conductor in the stator slot through the elastic force.

[0007] However, the spring design also has some problems:

[0008] (1) After the spring is inserted into the stator slot, a special tool is needed to compress and deform the spring to leave more space for the copper conductor to be inserted smoothly. After the copper conductor is inserted into the stator slot, the spring is released, and the spring undergoes elastic deformation, thereby fixing the copper conductor in the stator slot through elastic force. Therefore, the installation process is complicated, the tools used are complex, the installation cost is high, and the production speed is low.

[0009] (2) The copper conductors in each slot must be fixed by springs, which increases the number of parts and increases the cost of parts.

[0010] (3) The spring occupies the space in the slot, reducing the slot fill factor and lowering the motor performance.

[0011] (4) The copper conductor is pressed tightly against one side of the tank by the spring. The contact area between the copper conductor and the cooling oil is small, and the cooling effect in the tank is poor. Summary of the Invention

[0012] The purpose of this application is to overcome or at least mitigate at least one of the deficiencies of the prior art described above, and to provide a slot-cooled stator, a motor, and a method for fixing the windings of a slot-cooled stator.

[0013] The slot-cooled stator provided in this application includes:

[0014] A stator core and a winding, wherein the winding is installed in a stator slot of the stator core and a gap is provided between the winding and the stator slot;

[0015] An oil cover is disposed at both axial ends of the stator core and covers the portion of the winding protruding from the stator core. In the axial direction, an adhesive for fixing the winding is disposed on the side of the inner cavity of the oil cover away from the stator core. The side of the adhesive facing the stator core in the solidified state defines a cooling oil receiving cavity, which is connected to the stator slot.

[0016] In at least one embodiment, the oil cover includes a first oil cover and a second oil cover disposed at both axial ends of the winding, and both the first oil cover and the second oil cover are provided with oil passages communicating with the cooling oil receiving cavity and the outside.

[0017] In at least one embodiment, the oil passage includes an inner opening facing the stator core, and axially, the inner opening is located between the stator core and the adhesive.

[0018] In at least one embodiment, the oil passage extends along the axial direction and communicates with the outside from the oil passage opening located on the end face of the oil cover. In the axial direction, the distance between the side of the adhesive facing the stator core and the bottom surface of the adhesive is D1, and the distance between the inner opening of the oil passage and the bottom surface of the adhesive is D2, where D1 < D2.

[0019] In at least one embodiment, the slot-cooled stator includes an end cover disposed between the stator core and the oil cover, the end cover having an end cover hole communicating with the stator slot and the cooling oil receiving cavity, the winding passing through the end cover hole and having a gap between it and the end cover hole.

[0020] In at least one embodiment, the inner wall of the oil cover is provided with ribs that protrude toward the stator core.

[0021] In at least one embodiment, the oil cover includes a plurality of said ribs arranged in an alternating manner.

[0022] In at least one embodiment, the rib is located on the inner wall of the oil cover at the end away from the stator core.

[0023] The motor provided in this application includes the slot-cooled stator as described above.

[0024] The winding fixing method for slot-cooled stators provided in this application includes:

[0025] A stator core and a winding are provided, wherein the winding is installed in the stator slot of the stator core and a gap is provided between the winding and the stator slot;

[0026] Two oil covers are provided, which are disposed at both axial ends of the stator core and cover the portion of the winding that protrudes from the stator core.

[0027] Make the axis of the stator core parallel to the vertical line, with the oil cover at one end below and the oil cover at the other end above.

[0028] Apply adhesive to the oil cover below, the adhesive comes into contact with the winding, and the adhesive solidifies;

[0029] Flip the tank cooling stator and reverse the positions of the two oil covers;

[0030] Apply adhesive to the oil cover below, the adhesive comes into contact with the winding, and the adhesive solidifies. Attached Figure Description

[0031] Figure 1 shows a cross-sectional view of a slot-cooled stator according to an embodiment of the present application, with its axis horizontal.

[0032] Figure 2 shows a cross-sectional view of a slot-cooled stator according to an embodiment of the present application, with its axis vertical and glue disposed in the oil cover below.

[0033] Figure 3 shows a cross-sectional view of a slot-cooled stator according to an embodiment of the present application, with its axis vertical and glue provided in the upper and lower oil covers.

[0034] Figure 4 shows a schematic diagram of the first oil cover of the slot-cooled stator according to an embodiment of the present application, with its outer wall surface facing upward.

[0035] Figure 5 shows a schematic diagram of the first oil cover in Figure 4, with its inner wall facing upwards.

[0036] Figure 6 shows a schematic diagram of the second oil cover of the slot-cooled stator according to an embodiment of the present application, with its outer wall surface facing upward.

[0037] Figure 7 shows a schematic diagram of the second oil cover in Figure 6, with its inner wall facing upwards.

[0038] Figure 8 shows a schematic diagram of a slot-cooled stator according to an embodiment of the present application, omitting the oil cover.

[0039] Figure 9 shows a schematic diagram of a slot-cooled stator according to an embodiment of this application, omitting the oil cover. Detailed Implementation

[0040] Exemplary embodiments of this application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are for teaching those skilled in the art how to implement this application only, and are not intended to exhaustively describe all possible methods of this application, nor to limit the scope of this application.

[0041] This application provides a slot-cooled stator, a motor, and a method for fixing the windings of the slot-cooled stator. Exemplarily, the slot-cooled stator can be the stator in a motor of an electric vehicle. The electric vehicle can be a pure electric vehicle or a hybrid electric vehicle.

[0042] Referring to Figure 1, the slot-cooled stator provided in the embodiments of this application may include a stator core 100, a winding 200, and an oil cover 300.

[0043] The winding 200 is installed in the stator slot of the stator core 100, and a gap is provided between the winding 200 and the stator slot. Cooling oil can contact the winding 200 through this gap, thereby exerting a cooling effect. It is understood that the description of a gap between the winding 200 and the stator slot is general, including providing a gap between the winding 200 and the stator slot and / or providing a gap between the conductors of the winding 200. The gap between the winding 200 and the stator slot can specifically be the gap between the insulation layer (e.g., insulating paper) and the inner wall of the stator slot and / or the gap between the winding 200 and the insulation layer (e.g., insulating paper). The winding 200 can be a flat wire winding.

[0044] An oil cover 300 can be disposed at both ends of the stator core 100 in the axial direction (direction A in the figure, the same below), and covers the portion of the winding 200 protruding from the stator core 100. In the axial direction, an adhesive 500 for fixing the winding 200 is disposed on the side of the inner cavity of the oil cover 300 away from the stator core 100. The adhesive 500 contacts the winding 200, and a cooling oil receiving cavity 310 is defined on the side of the adhesive 500 facing the stator core 100. The cooling oil receiving cavity 310 communicates with the stator slot. Therefore, cooling oil can enter the stator slot through the cooling oil receiving cavity 310 to exchange heat and cool the winding 200 therein.

[0045] Referring to Figure 2, by way of example, the stator axis can be initially aligned parallel to the vertical direction. One end of the oil cover 300 (e.g., the first oil cover 301) can be placed downwards, and adhesive 500 can be applied into the oil cover 300, allowing it to solidify. Referring to Figure 3, after the adhesive 500 has solidified, the oil cover 300 at the other end (e.g., the second oil cover 302) is flipped downwards, and adhesive 500 is applied into it, allowing it to solidify again. This allows the adhesive 500, winding 200, and oil cover 300 to be fixed together, thus securing the winding 200. The space in the oil cover 300 not filled with adhesive 500 forms a cooling oil receiving cavity 310, through which cooling oil can be supplied to the stator slots, achieving oil-cooled heat exchange.

[0046] It is understood that this application fixes the adhesive 500 in the oil cover 300 instead of in the stator slot, and reserves a channel for cooling oil to enter the stator slot, thus achieving both adhesive fixation and slot-type cooling. Compared to the spring solution mentioned in the background art, this application does not require the use of specific spring compression tools, and the oil cover 300 has a simple structure; it only requires adding adhesive 500 to the oil cover 300 and waiting for it to solidify, making the operation simple. Overall, the production cost is low and the production efficiency is high.

[0047] This application does not contain any additional parts such as springs in the stator slots, resulting in low part costs and no impact on slot fill factor or motor performance. Furthermore, the winding 200 in this application is not pressed to one side of the stator slot by the springs, thus allowing for a relatively large contact area between the winding 200 and the cooling oil, leading to better cooling performance.

[0048] In one embodiment, referring to Figures 1, 4, and 6, the oil cover 300 may include a first oil cover 301 and a second oil cover 302 disposed at both axial ends of the winding 200. Both the first oil cover 301 and the second oil cover 302 are provided with oil passages 320 communicating with the cooling oil receiving cavity 310 and the outside. For example, the oil passage 320 of the first oil cover 301 can serve as an oil inlet 3201, and the oil passage 320 of the second oil cover 302 can serve as an oil outlet 3202. Cooling oil can enter the cooling oil receiving cavity 310 of the first oil cover 301 through the oil inlet 3201, then enter the cooling oil receiving cavity 310 of the second oil cover 302 through the stator slot, and then exit from the oil outlet 3202.

[0049] In one embodiment, referring to FIG1, the oil passage 320 includes an inner opening 321 facing the stator core 100, which is located axially between the stator core 100 and the adhesive 500. That is, the inner opening 321 is closer to the stator core 100 than the adhesive 500, so that, as shown in FIG2, the adhesive 500 can solidify below the inner opening 321, preventing the adhesive 500 from flowing out of the oil passage 320.

[0050] Further, referring to Figure 1, the oil passage 320 can extend axially and connect to the outside from the oil passage outer opening 322 located on the end face of the oil cover 300. In the axial direction, the distance between the side of the glue 500 (in the solidified state) facing the stator core 100 and the bottom surface of the glue 500 is D1, and the distance between the oil passage inner opening 321 and the bottom surface of the glue 500 is D2, where D1 < D2.

[0051] Furthermore, the glue injection port of the glue injection device (not shown in the figure) can be extended from the oil passage 320 into the inner cavity of the oil cover 300, and then glue can be injected. The distance D1 between the side of the glue 500 facing the stator core 100 after solidification and the bottom surface of the glue 500 can be controlled by controlling the amount of glue injected, so as to prevent the glue 500 from overflowing the inner opening 321 of the oil passage.

[0052] In one embodiment, referring to Figures 1, 8, and 9, the slot-cooled stator may further include an end cap 400. The end cap 400 is disposed between the stator core 100 and the oil cover 300 (the oil cover 300 is hidden in Figures 8 and 9). The end cap 400 has an end cap hole 410 communicating with the stator slot and the cooling oil receiving cavity 310. The winding 200 passes through the end cap hole 410 and has a gap with the end cap hole 410. Exemplarily, the end cap 400 can be fixed to the stator core 100, and the oil cover 300 can be fixed to the end cap 400. Of course, the slot-cooled stator may include two end caps 400 disposed at both ends of the stator core 100.

[0053] In one embodiment, referring to Figures 5 and 7, the inner wall of the oil cover 300 may be provided with ribs 330 protruding towards the stator core 100. Correspondingly, referring to Figures 8 and 9, corresponding recesses are formed on the solidified adhesive 500. The ribs 330 can increase the contact area between the adhesive 500 and the oil cover 300, which facilitates strengthening the adhesion between the adhesive 500 and the oil cover 300, making the fixing of the winding 200 more reliable.

[0054] Furthermore, multiple staggered ribs 330 can be provided on the inner wall. For example, the ribs 330 may include multiple first ribs 331 arranged in an array in the circumferential direction and circularly extending second ribs 332, with the first ribs 331 and the second ribs 332 staggered.

[0055] Furthermore, the rib 330 can be located on the inner wall of the end of the oil cover 300 away from the stator core 100, corresponding to the location where the glue 500 solidifies.

[0056] The motor provided in this application embodiment may include the aforementioned slot-cooled stator, and the motor may be a motor in an electric vehicle. The electric vehicle may be a pure electric vehicle or a hybrid electric vehicle.

[0057] Referring to Figures 2 and 3, the winding fixing method for a slot-cooled stator provided in this application may include:

[0058] A stator core 100 and a winding 200 are provided. The winding 200 is installed in the stator slot of the stator core 100, and a gap is provided between the winding 200 and the stator slot.

[0059] Two oil covers 300 are provided, which are disposed at both ends of the stator core 100 and cover the portion of the winding 200 that protrudes from the stator core 100.

[0060] Make the axis of the stator core 100 parallel to the vertical line, with the oil cover 300 at one end at the bottom and the oil cover 300 at the other end at the top.

[0061] Apply glue 500 to the oil cover 300 below, and the glue 500 contacts the winding 200 to solidify.

[0062] The stator is cooled by flipping the tank, and the positions of the two oil covers are reversed by 300 degrees.

[0063] Apply adhesive 500 to the lower oil cover 300, and the adhesive 500 contacts the winding 200 to solidify.

[0064] This method allows for the potting and fixing of the windings. The fixing position is located in the oil cover, and the stator slots are not affected, allowing for normal heat exchange through the cooling oil.

[0065] It should be understood that at least some aspects or features of the above-described implementation methods, embodiments, or examples can be appropriately combined.

[0066] It is understood that, in this application, when the number of parts or components is not specifically limited, the number can be one or more, where multiple refers to two or more. For cases where the number of parts or components shown in the drawings and / or described in the specification is, for example, two, three, four, etc., this specific number is generally exemplary and not restrictive, and can be understood as multiple, i.e., two or more; however, this does not mean that this application excludes the case of one.

[0067] This application is not limited to the above-described embodiments, examples, or examples. Those skilled in the art can make various modifications to the above-described embodiments, examples, or examples without departing from the scope of this application, based on the teachings of this application.

[0068] List of reference numerals: 100 Stator core; 200 Winding; 300 Oil cover; 301 First oil cover; 302 Second oil cover; 310 Cooling oil receiving cavity; 320 Oil passage; 3201 Oil inlet; 3202 Oil outlet; 321 Inner opening of oil passage; 322 Outer opening of oil passage; 330 Rib; 331 First rib; 332 Second rib; 400 End cap; 410 End cap hole; 500 Glue.

Claims

1. A tank-cooled stator, wherein, The slot-cooled stator includes: Stator core (100) and winding (200), wherein the winding (200) is installed in the stator slot of the stator core (100) and a gap is provided between the winding (200) and the stator slot; An oil cover (300) is disposed at both ends of the stator core (100) and covers the portion of the winding (200) protruding from the stator core (100). In the axial direction, an adhesive (500) for fixing the winding (200) is disposed on the side of the inner cavity of the oil cover (300) away from the stator core (100). The side of the adhesive (500) in the solidified state facing the stator core (100) defines a cooling oil receiving cavity (310), which is connected to the stator slot.

2. The slot-cooled stator according to claim 1, characterized in that, The oil cover (300) includes a first oil cover (301) and a second oil cover (302) disposed at both axial ends of the winding (200). Both the first oil cover (301) and the second oil cover (302) are provided with oil passages (320) that connect the cooling oil receiving cavity (310) and the outside.

3. The slot-cooled stator according to claim 2, characterized in that, The oil passage (320) includes an inner opening (321) facing the stator core (100), and in the axial direction, the inner opening (321) is located between the stator core (100) and the adhesive (500).

4. The slot-cooled stator according to claim 3, characterized in that, The oil passage (320) extends along the axial direction and communicates with the outside from the oil passage opening (322) located on the end face of the oil cover (300). In the axial direction, the distance between the side of the glue (500) facing the stator core (100) and the bottom surface of the glue (500) is D1, and the distance between the inner opening (321) of the oil passage and the bottom surface of the glue (500) is D2, where D1 < D2.

5. The slot-cooled stator according to claim 1, characterized in that, The slot-cooled stator includes an end cap (400) disposed between the stator core (100) and the oil cover (300). The end cap (400) has an end cap hole (410) that connects the stator slot and the cooling oil receiving cavity (310). The winding (200) passes through the end cap hole (410) and has a gap with the end cap hole (410).

6. The slot-cooled stator according to claim 1, characterized in that, The inner wall of the oil cover (300) is provided with ribs (330) that protrude toward the stator core (100).

7. The slot-cooled stator according to claim 6, characterized in that, The oil cover (300) includes a plurality of staggered ribs (330).

8. The slot-cooled stator according to claim 6, characterized in that, The rib (330) is located on the inner wall of the oil cover (300) at the end away from the stator core (100).

9. An electric motor, wherein, Includes the tank-cooled stator according to any one of claims 1 to 8.

10. A method for fixing the windings of a slot-cooled stator, wherein, include: A stator core (100) and a winding (200) are provided. The winding (200) is installed in the stator slot of the stator core (100), and a gap is provided between the winding (200) and the stator slot. Two oil covers (300) are provided, which are disposed at both axial ends of the stator core (100) and cover the portion of the winding (200) protruding from the stator core (100); Make the axis of the stator core (100) parallel to the vertical line, with the oil cover (300) at one end below and the oil cover (300) at the other end above. Apply adhesive (500) to the oil cover (300) below, the adhesive (500) contacts the winding (200), and the adhesive (500) solidifies; Flip the tank cooling stator and reverse the positions of the two oil covers (300); Apply adhesive (500) to the oil cover (300) below, the adhesive (500) comes into contact with the winding (200), and the adhesive (500) solidifies.

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