Inner-cooling forming flat wire winding based on separable stator and winding method of inner-cooling forming flat wire winding

Abstract

The invention discloses an inner-cooling forming flat wire winding based on a separable stator and a winding method of the inner-cooling forming flat wire winding. In the winding forming process, a wave winding flat wire winding structure is adopted to enable windings to be tightly arranged, and efficient current conduction and space utilization are achieved; and during installation, the winding can be integrally and smoothly inserted through the open slot structure, so that the convenience and the efficiency of the production process are improved. After winding inserting is completed, the separable tooth crests are in close fit with the stator teeth, the open slot structure is converted into the semi-open slot structure, and the problems that due to the traditional open slot design, the magnetic flux density is not uniform, and the cogging torque pulsation is too large are solved. The conversion of the structure not only improves the air gap flux density distribution of the motor and reduces the mechanical vibration and energy loss during operation, but also remarkably improves the stability of the motor and the reliability of long-term operation.

Description

Technical Field

[0001] The invention belongs to the field of motor stator windings, and in particular relates to an internally cold-formed flat wire winding based on a separable stator and a winding method thereof. Background Art

[0002] The rapid development of new energy vehicles has led to an increasing demand for high-performance permanent magnet drive motors. Flat wire motors have become the first choice for electric vehicle permanent magnet drive systems due to their unique rectangular flat wire structure, high slot fill rate and excellent heat dissipation performance. This design effectively improves the power density of the motor, significantly enhances the overall performance of the motor, and meets the dual requirements of new energy vehicles in terms of size and power.

[0003] However, due to the influence of skin effect and proximity effect, the eddy current loss of flat wire windings cannot be ignored in applications, especially near the slots. Under high-frequency conditions, eddy current loss is particularly significant, resulting in a significant increase in the local temperature rise of the winding. This temperature rise not only affects the overall efficiency of the motor, but may also cause aging of the insulation material, thereby shortening the service life of the motor. In addition, the temperature increase may cause overheating problems, which in turn affects the long-term stability and reliability of the motor. Therefore, reducing the eddy current loss of flat wire windings and effectively controlling the temperature rise are key challenges to improving motor performance.

[0004] Wave windings, with their advantages of fewer welding points and short ends, significantly reduce the incidence of potential motor failures, while effectively reducing DC losses, thereby improving the overall reliability of the motor. However, in order to facilitate the offline operation of wave windings, the slot type is usually designed as an open slot. Although this slotted structure is convenient, it will lead to uneven distribution of magnetic flux density between tooth slots, which will in turn cause large tooth slot torque pulsation and affect the smooth operation of the motor. In addition, uneven magnetic flux distribution may lead to local saturation, further increasing torque fluctuations and heat losses. Therefore, it is necessary to comprehensively consider the advantages of windings and the potential impact of slot structures on motor performance to achieve the best operating effect.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide an internally cold-formed flat wire winding based on a separable stator and a winding method thereof, thereby solving the problems raised in the above-mentioned background technology.

[0007] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0008] An internal cold-formed flat wire winding based on a separable stator comprises a stator core and a separable tooth top, wherein the stator core comprises a stator yoke in an annular structure, a plurality of stator teeth are fixedly connected in an annular arrangement on the inner wall circumference of the stator yoke, parallel stator slots are formed between every two adjacent stator teeth, and the slot openings are in an open slot structure;

[0009] Flat wire windings are installed inside the parallel stator slots, the separable tooth tops are connected to the ends of the stator teeth and assembled after the windings are offline, so that the open slot structure is transformed into a semi-open slot structure, thereby improving the magnetic flux distribution of the motor.

[0010] Optionally, the flat wire winding includes a solid flat wire winding and a hollow flat wire winding arranged in sequence from the inside to the outside, and a cooling medium is passed through the hollow parts of the hollow flat wire windings. The first to fourth layers of flat wire windings close to the parallel stator slot openings are hollow flat wire windings, and the fifth to eighth layers of flat wire windings away from the parallel stator slot openings are solid flat wire windings.

[0011] Optionally, the top of the separable tooth top is a trapezoidal structure, one side of the trapezoidal structure is provided with a rectangular protrusion, and the side of the stator tooth away from the stator yoke is provided with a rectangular groove matched with the rectangular protrusion.

[0012] Optionally, after the rectangular protrusion enters the rectangular groove, one side of the detachable tooth top is tightly fitted on one side of the stator tooth.

[0013] Optionally, both the hollow flat wire winding and the solid flat wire winding are wound inside parallel stator slots using a shaped wave winding structure, and are connected at the ends to form different branches of the three-phase winding.

[0014] Optionally, the cooling medium includes but is not limited to water or ethanol.

[0015] A winding method for an internally cold-formed flat wire winding based on a separable stator comprises the following steps:

[0016] Step S1: performing wave winding of the hollow flat wire winding and the solid flat wire winding according to a predetermined path, and introducing the solid flat wire winding into the eighth layer of the stator slot, and completing initial fixation at the starting slot position of the stator core according to the winding rule;

[0017] Step S2: arranging the solid flat wire winding layer by layer on the eighth to fifth layers of the stator slots near the bottom of the slots according to a predetermined path. After the solid flat wire winding is completed, continue to arrange the hollow flat wire winding layer by layer on the fourth to first layers of the stator slots according to the predetermined path;

[0018] Step S3: After completing the winding of each layer, the flat wire ends of the hollow and solid windings are connected to form different branches of the three-phase winding;

[0019] Step S4: After winding is completed, the rectangular protrusion of the detachable tooth top is inserted into the groove of the stator tooth to fix the winding structure and convert the open slot into a semi-open slot. Finally, the cooling system is connected to the hollow flat wire winding and the cooling medium is introduced.

[0020] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art. Of course, any product implementing the present invention does not necessarily need to achieve all the advantages described below at the same time:

[0021] 1. During the winding forming process, the present invention adopts a wave-wound flat wire winding structure to arrange the windings closely, realizing efficient current conduction and space utilization; during installation, the open slot structure facilitates the smooth offline of the winding as a whole, thereby improving the convenience and efficiency of the production process. After the winding is offline, the open slot structure is converted into a semi-open slot structure by closely matching the separable tooth top with the stator tooth, thus avoiding the problems of uneven magnetic flux density and excessive tooth slot torque pulsation caused by the traditional open slot design. The conversion of this structure not only improves the air gap magnetic flux distribution of the motor, reduces mechanical vibration and energy loss during operation, but also significantly improves the stability of the motor and the reliability of long-term operation.

[0022] 2. The hollow flat wire winding provided by the present invention effectively blocks the eddy current loop path through its unique hollow structure design, and avoids the generation of eddy currents on the conductor surface or between adjacent windings by high-frequency currents. This design reduces the electromagnetic coupling effect, limits the generation of eddy currents from the root, makes the density distribution of current in the winding more uniform, and avoids the phenomenon of local current concentration. In addition, the uniform current distribution not only reduces the ineffective loss of electric energy, but also reduces the formation of local hot spots, prevents aging or performance degradation of insulating materials due to excessive temperature rise, thereby improving the heat dissipation efficiency and operation stability of the motor. Through this hollow structure design, the motor can maintain low-loss operation under high-frequency and high-load conditions, effectively prolongs the service life of the winding, and significantly improves the overall efficiency and reliability of the motor.

[0023] 3. The hollow flat wire winding provided by the present invention has a design in which a coolant can be passed into the inside. The flow of the coolant further enhances the heat dissipation performance of the motor, ensuring that the winding maintains a low temperature when under high load or for a long time. The coolant is evenly distributed through the flow channel inside the winding, quickly taking away the heat generated during operation and avoiding local overheating. The effective control of temperature rise not only slows down the aging rate of the winding material, but also avoids the problem of increased flat wire resistance due to increased temperature, thereby reducing energy loss and ensuring the stability of the electrical performance of the motor. In addition, this cooling design enables the motor to maintain a high conversion efficiency when operating at high frequency, avoids the problem of frequency reduction or shutdown due to insufficient heat dissipation, and improves the long-term reliability and operating life of the system.

[0024] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described below are only some embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0026] In the figure:

[0027] Figure 1 It is a plan schematic diagram of the internally cold-formed flat wire winding based on a separable stator.

[0028] Figure 2 It is a partial schematic diagram of the separable stator.

[0029] Figure 3 The three-dimensional schematic diagram of the separable tooth top with protrusions.

[0030] Figure 4 A three-dimensional schematic diagram of a stator tooth with grooves.

[0031] Figure 5 Schematic diagram of the distribution of hollow flat wire windings and solid flat wire windings in a slot.

[0032] Figure 6 This is the winding expansion diagram of the two branches of the A-phase winding.

[0033] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0034] 1. stator core; 10. stator yoke; 11. stator teeth; 12. stator slots; 13. cuboid grooves;

[0035] 2. Separable tooth top; 21. Rectangular protrusion;

[0036] 3. Hollow flat wire winding; 31. Cooling medium; 4. Solid flat wire winding.

[0037] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0038] The present invention will now be described in further detail with reference to the accompanying drawings.

[0039] See also Figure 1-6As shown, in this embodiment, an internal cold-formed flat wire winding based on a separable stator is provided, comprising a stator core 1 and a separable tooth top 2, wherein the stator core 1 comprises a stator yoke 10 in an annular structure, and a plurality of stator teeth 11 are fixedly connected in an annular arrangement on the inner wall circumference of the stator yoke 10, and parallel stator slots 12 are formed between every two adjacent stator teeth 11, and the slots are in an open slot structure;

[0040] The parallel stator slots 12 are internally installed with flat wire windings, and the separable tooth tops 2 are connected to the ends of the stator teeth 11 and assembled after the winding is offline, so that the open slot structure is transformed into a semi-open slot structure, thereby improving the magnetic flux distribution of the motor. The present invention achieves multiple optimization effects by using the stator core 1 in conjunction with the separable tooth tops 2 to transform the original open slot structure into a semi-open slot structure after the winding is offline. First, the open slot structure facilitates the installation of the winding and improves production efficiency; and after the installation is completed, the magnetic flux unevenness caused by the open slots is effectively reduced through the tight assembly of the separable tooth tops, reducing torque pulsation, thereby improving the running stability and efficiency of the motor. In addition, the flexibility of this structure helps to improve maintenance convenience and ensure long-term stable and reliable operation of the motor.

[0041] In this embodiment, the flat wire winding includes a solid flat wire winding 4 and a hollow flat wire winding 3 arranged in sequence from the inside to the outside, and the hollow parts of the hollow flat wire windings 3 are all passed through cooling medium 31. The first to fourth layers of flat wire windings close to the openings of the parallel stator slots 12 are hollow flat wire windings 3, and the fifth to eighth layers of flat wire windings away from the openings of the parallel stator slots 12 are solid flat wire windings 4. By arranging the shaped hollow flat wire winding 3 in the outer layer close to the openings of the parallel stator slots 12 and introducing the cooling medium 31 in its hollow part, the heat dissipation effect is effectively improved, and the adverse effect of temperature rise on the performance of the motor is significantly reduced. At the same time, the hollow structure blocks the eddy current path, ensures uniform current distribution, reduces eddy current loss, and thus improves the efficiency and reliability of the motor. Arranging the solid flat wire winding 4 in the inner layer away from the openings of the parallel stator slots 12 not only enhances the mechanical strength and structural stability of the winding, but also optimizes the electromagnetic performance through the alternating layout of the inner and outer layers, further improving the overall operating efficiency and long-term stability of the motor.

[0042] In this embodiment, the top of the detachable tooth top 2 is a trapezoidal structure, and a rectangular protrusion 21 is provided on one side of the trapezoidal structure, and a rectangular groove 13 matching the rectangular protrusion 21 is provided on the side of the stator tooth 11 away from the stator yoke 10. After the rectangular protrusion 21 enters the rectangular groove 13, one side of the detachable tooth top 2 fits tightly against one side of the stator tooth 11. The present invention not only ensures a firm connection between the tooth top and the stator tooth through installation in this way, but also improves the structural stability of the winding after installation, and prevents mechanical vibration or torque fluctuation caused by looseness. In addition, the structure is more flexible during assembly and disassembly, which is helpful for the maintenance and replacement of the winding, while reducing the installation deviation caused by mechanical errors, ensuring the stability of the motor during operation and the uniform distribution of magnetic flux density.

[0043] In this embodiment, the hollow flat wire winding 3 and the solid flat wire winding 4 are both wound inside the parallel stator slots 12 using a shaped wave winding structure, and are connected at the ends to form different branches of the three-phase winding. The wave winding structure ensures the close arrangement of the windings and the stability of the current path; secondly, the alternating arrangement of the hollow and solid windings helps to optimize the electromagnetic performance and achieve a more uniform current distribution; finally, the independent branches are formed by connecting the ends, which enhances the phase-to-phase electrical isolation of the motor and improves the stability and reliability of the overall operation.

[0044] In this embodiment, the cooling medium includes but is not limited to one of water and ethanol, and can provide multiple properties such as efficient heat dissipation, low-temperature antifreeze, anti-corrosion and antibacterial according to application requirements to ensure stable and efficient operation of the motor.

[0045] A winding method for an internally cold-formed flat wire winding based on a separable stator comprises the following steps:

[0046] Step S1: performing wave winding of the hollow flat wire winding 3 and the solid flat wire winding 4 according to a predetermined path, and introducing the solid flat wire winding 4 into the eighth layer of the stator slot 12, and completing initial fixation at the starting slot position of the stator core 1 according to the winding rule;

[0047] Step S2: Arrange the solid flat wire winding 4 layer by layer on the eighth to fifth layers near the bottom of the stator slot 12 according to a predetermined path. After the solid flat wire winding is completed, continue to arrange the hollow flat wire winding 3 layer by layer on the fourth to first layers of the stator slot 12 according to the predetermined path.

[0048] Step S3: After completing the winding of each layer, the flat wire ends of the hollow and solid windings are connected to form different branches of the three-phase winding;

[0049] Step S4: After winding is completed, the rectangular protrusion 21 of the separable tooth top 2 is inserted into the groove 13 of the stator tooth 11 to fix the winding structure and convert the open slot into a semi-open slot. Finally, the cooling system is connected to the hollow flat wire winding 3 and the cooling medium is introduced.

[0050] Take the A phase winding as an example. Figure 4 As shown, the relevant flat wire winding is wave-wound into phase A 1 branch, marked as a(b) as the winding of slot a and layer b, with a first pitch of 5 and a composite pitch of 12. The first pitch is 5, which means that during the winding process, 5 slots are crossed between adjacent flat wires. This ensures uniform distribution between windings. The composite pitch is 12, which means that the winding crosses 12 slots in a complete winding cycle. This design helps to reduce the cogging torque pulsation during motor operation. A1 and A2 represent different branches of the winding in phase A of the motor, and each branch corresponds to a winding arranged in a specific slot and layer. X1 and X2 are the end symbols of each branch, indicating the positions where the first branch A1 and the second branch A2 of the phase A winding end.

[0051] Specific description of the path of the hollow winding branch: A1-7(1)-2(2)-43(1)-38(2)-31(1)-26(2)-19(1)-14(2)-8(1)-3(2)-44(1)-39(2)-32(1)-27(2)-20(1)-15(2)-7(3)-2(4)-43(3)-38(4)-31(3)-26(4)-19(3)-14(4)-8(3)-3(4)-44(3)-39(4)-32(3)-27(4)-20(3) -15(4)-8(4)-13(3)-20(4)-25(3)-32(4)-37(3)-44(4)-1(3)-9(4)-14(3)-21(4)-26(3)-33(4)-38(3)-45(4)-2(3 )-8(2)-13(1)-20(2)-25(1)-32(2)-37(1)-44(2)-1(1)-9(2)-14(1)-21(2)-26(1)-33(2)-38(1)-45(2)-2(1)-X1.

[0052] The relevant flat wire winding is wave-wound into two branches of phase A, with a(b) marking the b-layer winding in slot a. The path of the solid winding branch is described in detail:

[0053] A2-7(5)-2(6)-43(5)-38(6)-31(5)-26(6)-19(5)-14(6)-8(5)-3(6)-44(5)-39(6)-32(5)-27(6)-20(5)-15(6 )-7(7)-2(8)-43(7)-38(8)-31(7)-26(8)-19(7)-14(8)-8(7)-3(8)-44(7)-39(8)-32(7)-27(8)-20(7)-15(8)- 2(5)-45(6)-38(5)-33(6)-26(5)-21(6)-14(5)-9(6)-1(5)-44(6)-37(5)-32(6)-25(5)-20(6)-13(5)-8(6)-2 (7)-45(8)-38(7)-33(8)-26(7)-21(8)-14(7)-9(8)-1(7)-44(8)-37(7)-32(8)-25(7)-20(8)-13(7)-8(8)-X2.

[0054] The present invention is not limited to the above-mentioned embodiments. Anyone should be aware that any structural changes made under the enlightenment of the present invention, and any technical solutions that are the same or similar to the present invention, fall within the protection scope of the present invention. The technology, shape, and structural parts not described in detail in the present invention are all well-known technologies.

Claims

1. An internal cold-formed flat wire winding based on a separable stator and a winding method thereof, characterized in that: include: A stator core (1) and a separable tooth top (2), wherein the stator core (1) comprises a stator yoke (10) in an annular structure, a plurality of stator teeth (11) are fixedly connected in an annular arrangement on the inner wall circumference of the stator yoke (10), and parallel stator slots (12) are formed between every two adjacent stator teeth (11), and the slot openings are in an open slot structure; A flat wire winding is installed inside the parallel stator slots (12), the separable tooth top (2) is connected to the end of the stator tooth (11), and is assembled after the winding is offline, so that the open slot structure is transformed into a semi-open slot structure, thereby improving the magnetic flux distribution of the motor.

2. The internal cold-formed flat wire winding based on a separable stator and the winding method thereof according to claim 1, characterized in that: The flat wire winding comprises a solid flat wire winding (4) and a hollow flat wire winding (3) which are arranged in sequence from the inside to the outside. A cooling medium (31) is passed through the hollow parts of the hollow flat wire windings (3). The first to fourth layers of flat wire windings close to the openings of the parallel stator slots (12) are hollow flat wire windings (3), and the fifth to eighth layers of flat wire windings far from the openings of the parallel stator slots (12) are solid flat wire windings (4).

3. The internal cold-formed flat wire winding based on a separable stator and the winding method thereof according to claim 2, characterized in that: The top of the separable tooth top (2) is in a trapezoidal structure, one side of the trapezoidal structure is provided with a rectangular parallelepiped protrusion (21), and the side of the stator tooth (11) away from the stator yoke (10) is provided with a rectangular parallelepiped groove (13) adapted to the rectangular parallelepiped protrusion (21).

4. The internal cold-formed flat wire winding based on a separable stator and the winding method thereof according to claim 3, characterized in that: After the rectangular parallelepiped protrusion (21) enters the rectangular parallelepiped groove (13), one side of the detachable tooth top (2) is closely attached to one side of the stator tooth (11).

5. The internal cold-formed flat wire winding based on a separable stator and the winding method thereof according to claim 4, characterized in that: The hollow flat wire winding (3) and the solid flat wire winding (4) are both wound inside parallel stator slots (12) using a shaped wave winding structure, and are connected at the ends to form different branches of a three-phase winding.

6. The internal cold-formed flat wire winding based on a separable stator and the winding method thereof according to claim 5, characterized in that: The cooling medium includes but is not limited to water or ethanol.

7. A winding method for internally cold-formed flat wire windings based on a separable stator, characterized in that: The following steps are involved: Step S1: performing wave winding of the hollow flat wire winding (3) and the solid flat wire winding (4) according to a predetermined path, and introducing the solid flat wire winding (4) into the eighth layer of the stator slot (12), and completing initial fixation at the starting slot position of the stator core (1) according to the winding rule; Step S2: arranging the solid flat wire winding (4) layer by layer in the eighth to fifth layers of the stator slot (12) close to the slot bottom according to a predetermined path, and after the solid flat wire winding is completed, continuing to arrange the hollow flat wire winding (3) layer by layer in the fourth to first layers of the stator slot (12) according to the predetermined path; Step S3: After completing the winding of each layer, the flat wire ends of the hollow and solid windings are connected to form different branches of the three-phase winding; Step S4: After winding is completed, the rectangular protrusion (21) of the detachable tooth top (2) is inserted into the groove (13) of the stator tooth (11), the winding structure is fixed, and the open slot is converted into a semi-open slot. Finally, the cooling system is connected to the hollow flat wire winding (3) and a cooling medium is introduced.

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