Stator structure based on multi-layer flat wire winding

Abstract

The invention discloses a stator structure based on a multi-layer flat wire winding, which comprises a stator core and a plurality of motor windings, and is characterized in that a plurality of stator grooves penetrating through the two ends of the stator core along the axial direction are formed in the inner wall of the stator core along the circumferential direction; the motor winding comprises a plurality of layers of flat wire conductors which are distributed in the two stator slots at intervals; each layer of flat wire conductor comprises in-slot straight sections located in two stator slots, the corresponding ends of the two in-slot straight sections are connected through end connecting sections located outside the stator slots, and the other ends of the two in-slot straight sections are connected with the corresponding ends of the in-slot straight sections of the two adjacent layers of flat wire conductors through end connecting sections located outside the stator slots; the middle of the end connecting section is provided with a bending receding structure or an overturning transposition structure. Alternating current loss caused by the skin effect and the like can be reduced, the circulation effect is reduced, and therefore the motor efficiency is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of motor technology, and in particular to a new energy vehicle drive motor, and specifically to a stator structure based on a multi-layer flat wire winding. Background Art

[0002] With the continuous improvement of new energy vehicle technology, electric drive systems are increasingly developing towards high power density, high volume density, and high efficiency. Therefore, it is particularly important to improve motor efficiency and volume density.

[0003] As traditional flat wire motors develop towards higher speeds, the cross-sectional area of ​​their windings is large, and the skin effect and proximity effect are more obvious. Therefore, the impact of high-frequency AC losses on efficiency is particularly serious. Therefore, it is necessary to reduce the cross-sectional area of ​​a single winding to reduce high-frequency AC losses and improve motor efficiency.

[0004] However, in order to maintain a certain slot fill rate, the number of winding layers needs to be increased when the cross-sectional area of ​​a single winding is reduced, which makes the paths of the outermost and innermost copper wires in a single winding unequal in the stator core, and makes the inductance of the motor unbalanced, thus generating circulating current. The existence of circulating current in the motor will cause additional losses, noise and other problems, so a reasonable design of the winding structure is an effective way to reduce the negative impact of the motor circulating current, thereby improving the motor efficiency. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to solve the problems of large AC losses in existing motors, inductance imbalance due to differences in winding wire paths, which leads to circulating currents in the motors and reduced motor efficiency, and to provide a stator structure based on multi-layer flat wire windings that can reduce AC losses caused by skin effects, etc., and reduce circulating current effects, thereby effectively improving motor efficiency.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a stator structure based on a multi-layer flat wire winding, including a stator core and a plurality of motor windings, wherein a plurality of stator slots are opened on the inner wall of the stator core along its circumferential direction and axially penetrate the two ends of the stator core; the motor winding includes a plurality of layers of flat wire conductors, and the flat wire conductors are distributed in two stator slots at intervals; it is characterized in that each layer of flat wire conductor includes a straight segment in the slot located in two stator slots, and the corresponding ends of the straight segments in the two slots are connected through an end connecting segment located outside the stator slot, and the other end is connected to the corresponding ends of the straight segments in the slots of two adjacent layers of flat wire conductors through the end connecting segment located outside the stator slot; the middle part of the end connecting segment has a bending yielding structure or a flipping switching structure.

[0007] Furthermore, the straight sections in the two slots of the multi-layer flat wire conductor of the motor winding are arranged in parallel from the inside to the outside of the stator slot; the end connecting section also includes two connecting branch sections, which are formed by the straight section in the slot extending out of the stator slot and tilting toward the direction of the straight section in the other slot; the bent and yielding structure is an arc section bent in the direction away from the stator core, and its two ends are connected to the corresponding two connecting branch sections, and the projection of the arc section on a plane perpendicular to the axial centerline of the stator core is S-shaped, and the plane where the arc section is located is parallel to the axial centerline of the stator core, and the end connecting sections of the multi-layer flat wire conductor are also arranged in parallel from the inside to the outside of the stator slot.

[0008] Furthermore, the straight sections in the slots on one side of the multi-layer flat wire conductor of the motor winding are distributed in parallel from the inside to the outside of the stator slot, and the straight sections in the slots on the other side are distributed in parallel from the outside to the inside of the stator slot; the end connecting section also includes two connecting branch sections, and the connecting branch sections are formed by the straight section in the slot extending out of the stator slot and then tilting and twisting toward the direction of the straight section in the other slot; the flip-over structure is an arc section bent in the direction away from the stator core as a whole, and the two arms of the arc section are twisted in opposite directions and connected to the corresponding two connecting branch sections, and the plane in which it is located is perpendicular to or intersecting with the axial centerline of the stator core, and the flip-over structure of the end connecting section of the multi-layer flat wire conductor is arranged in parallel from top to bottom.

[0009] Furthermore, there is a distance between the bent yielding structure or the flipping shifting structure and the stator core, so that the end connecting section is V-shaped as a whole.

[0010] Furthermore, an insulating layer structure is coated on the outer side of the flat wire conductor.

[0011] Furthermore, the thickness of the flat wire conductor is 0.1 mm-3 mm.

[0012] Furthermore, the motor windings are arranged to form continuous wave windings, Hair-pin windings, X-pin windings or I-pin windings.

[0013] Furthermore, the middle part of the end connecting section at one end of the motor winding adopts a bending-yielding structure, and the middle part of the end connecting section at the other end adopts a flipping-yielding structure.

[0014] Further, the middle part of the end connecting section of some motor windings adopts a bending yielding structure, and the middle part of the end connecting section of some motor windings adopts a flipping yielding structure; or the middle part of the end connecting section of some motor windings adopts a bending yielding structure, the middle part of the end connecting section at one end of some motor windings adopts a bending yielding structure, and the middle part of the end connecting section at the other end adopts a flipping yielding structure; or the middle part of the end connecting section of some motor windings adopts a flipping yielding structure, the middle part of the end connecting section at one end of some motor windings adopts a bending yielding structure, and the middle part of the end connecting section at the other end adopts a flipping yielding structure; or the middle part of the end connecting section of some motor windings adopts a bending yielding structure, the middle part of the end connecting section of some motor windings adopts a flipping yielding structure, the middle part of the end connecting section at one end of some motor windings adopts a bending yielding structure, and the middle part of the end connecting section at the other end adopts a flipping yielding structure.

[0015] Compared with the prior art, the present invention has the following advantages: 1. It can effectively reduce AC loss: Due to the use of a multi-layer flat conductor line side-by-side structure, the cross-sectional area of ​​a single conductor is reduced, which can effectively reduce the skin effect and proximity effect. At the same time, combined with the end bending and giving way structure, it can reduce AC loss and improve the efficiency of the motor.

[0016] 2. Reduce the loss caused by the motor's circulating current: The end flip position structure can effectively reduce the circulating current caused by the inductance imbalance caused by the inconsistent path caused by the stacking of the flat wire conductor ends, thereby improving the motor efficiency.

[0017] 3. Reduce the risk of insulation damage caused by 3D forming of the winding wire end: When the thickness of the flat conductor wire becomes thinner and the end is 3D formed, the deformation caused by stretching or compression of the insulation layer is smaller, and the risk of insulation damage is reduced.

[0018] 4. Reduce the difficulty of the manufacturing process of continuous wave windings: The traditional continuous wave winding process has problems such as winding formation and arrangement difficulties. This solution can simplify the difficulties of continuous wave winding technology by reducing the hardness of the winding, so that this technology can be further applied to the drive motor industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of Example 1 of the present invention.

[0020] Figure 2 It is a schematic diagram of the bending and giving way structure in Example 1 of the present invention.

[0021] Figure 3 It is a side view of the bent-out structure in Example 1 of the present invention.

[0022] Figure 4Schematic diagram of the distribution of the straight segments in the stator slots in Example 1 of the present invention.

[0023] Figure 5 This is a schematic diagram of the structure of Example 2 of the present invention.

[0024] Figure 6 It is a schematic diagram of the flipping and giving way structure in Example 2 of the present invention.

[0025] Figure 7 It is a side view of the flipping and giving way structure in Example 2 of the present invention.

[0026] Figure 8 Schematic diagram of the distribution of the straight segments in the stator slots in Example 2 of the present invention.

[0027] Fig. 9 This is a schematic diagram of the structure of the Hair-pin winding arrangement.

[0028] Fig.10 This is a schematic diagram of the X-pin winding arrangement.

[0029] Fig.11 This is a schematic diagram of the structure of the I-pin winding arrangement.

[0030] In the figure: 1—stator core, 2—motor winding, 201—first layer of flat conductor wire, 202—second layer of flat conductor wire, 20n—nth layer of flat conductor wire, 3—stator slot, 301—stator slot A, 302—stator slot B, 4—straight section in the slot, 5—bending and giving way structure, 6—flipping and switching structure, 7—connecting branch section. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] Example 1: See Figure 1-Figure 3 A stator structure based on multi-layer flat wire windings includes a stator core 1 and a plurality of motor windings 2. The inner wall of the stator core 1 is provided with a plurality of stator slots 3 axially penetrating the two ends of the stator core 1 along its circumferential direction; the motor winding 2 includes a plurality of layers of flat wire conductors, and the flat wire conductors are spaced apart and distributed in the two stator slots 3. During implementation, an insulating layer structure is coated on the outer side of the straight section 4 in the slot of each layer of flat wire conductor, and the material, thickness, and composition of the outer insulating structure are not limited, as long as the insulation design requirements are met, such as insulating paper, insulating film, etc.

[0035] Each layer of flat wire conductor includes a slot straight section 4 located in two stator slots 3, wherein the width direction of the slot straight section 4 is consistent with the width direction of the stator slot 3. The corresponding ends of the two slot straight sections 4 are connected through the end connection section located outside the stator slot 3, and the other ends are connected to the corresponding ends of the slot straight sections 4 of the two adjacent layers of flat wire conductors through the end connection section located outside the stator slot 3; wherein the middle part of the end connection section has a bent yielding structure 5. Specifically, the two slot straight sections 4 of the multi-layer flat wire conductor of the motor winding 2 are arranged in parallel from the inside to the outside of the stator slot 3. The end connection section also includes two connecting branch sections 7, which are formed by the slot straight section 4 extending out of the stator slot 3 and tilting toward the other slot straight section 4. The bent-out structure 5 is an arc segment bent away from the stator core 1, and its two ends are connected to the corresponding two connecting branches 7. The projection of the arc segment on a plane perpendicular to the axis of the stator core 1 is S-shaped, and the plane where it is located is parallel to the axis of the stator core 1. The end connecting sections of the multi-layer flat wire conductor are also distributed in parallel from the inside to the outside of the stator slot 3. For easy assembly, there is a gap between the bent-out structure 5 and the stator core 1, so that the end connecting section is V-shaped as a whole.

[0036] As an example, see Figure 4 , multiple layers of flat wire conductors are arranged side by side, and the straight sections 4 in the two slots are arranged in sequence from the outside to the inside of the stator slot 3, similar to a whole winding wire of an ordinary flat wire structure divided into multiple thinner parallel winding wires, such as the straight sections 4 in the two slots are arranged in sequence from the outside to the inside in the stator slot 3: the first layer of flat conductor wire 201, the second layer of flat conductor wire 202, ... the nth layer of flat conductor wire 20n, n is a positive integer, the thickness of the flat conductor is 0.1mm-3mm, the width of the flat conductor wire is not limited, and it can meet the electromagnetic design requirements.

[0037] Example 2, see Figure 5-7 A stator structure based on multi-layer flat wire windings includes a stator core 1 and a plurality of motor windings 2. The inner wall of the stator core 1 is provided with a plurality of stator slots 3 axially penetrating the two ends of the stator core 1 along its circumferential direction; the motor winding 2 includes a plurality of layers of flat wire conductors, and the flat wire conductors are spaced apart and distributed in the two stator slots 3. During implementation, an insulating layer structure is coated on the outside of the straight section in the slot of each layer of flat wire conductor, and the material, thickness, and composition of the insulating structure are not limited, and can meet the insulation design requirements, such as insulating paper, insulating film, etc.

[0038] Each layer of flat wire conductor includes a slot straight segment 4 located in two stator slots 3, wherein the width direction of the slot straight segment 4 is consistent with the width direction of the stator slot 3. The corresponding ends of the two slot straight segments 4 are connected through the end connecting segment located outside the stator slot 3, and the other ends are connected to the corresponding ends of the slot straight segments 4 of the adjacent two layers of flat wire conductors through the end connecting segment located outside the stator slot 3; wherein the middle part of the end connecting segment has a flipping structure 6. Specifically, the slot straight segments 4 on one side of the multi-layer flat wire conductor of the motor winding 2 are all arranged in parallel from the inside to the outside of the stator slot 3, and the slot straight segments 4 on the other side are all arranged in parallel from the outside to the inside of the stator slot 3. The end connecting segment also includes two connecting branch segments 7, which are formed by the slot straight segment 4 extending out of the stator slot 3 and tilting and twisting toward the other slot straight segment 4. The flip-shift structure 6 is an arc segment that is bent away from the stator core 1. The two arms of the arc segment are twisted in opposite directions and connected to the corresponding two connecting branches 7. The plane where the flip-shift structure 6 is located is perpendicular to or intersects the axis of the stator core 1. The flip-shift structures 6 of the end connecting segments of the multi-layer flat wire conductor are arranged in parallel from top to bottom. For ease of assembly, there is a gap between the flip-shift structure 6 and the stator core 1, so that the end connecting segment is V-shaped as a whole.

[0039] As an example, see Figure 8 , the multi-layer flat wire conductor is flipped at the end, and a whole winding wire similar to an ordinary flat wire structure is divided into multiple thinner parallel winding wires and flipped at the end, such as the first layer of flat conductor wire, the second layer of flat conductor wire... the nth layer of flat conductor wire, n is a positive integer; the flipping causes the side-by-side positions in the connected front and rear slots to be inconsistent, and their position relationship can be described as: assuming that the stator slot A301 and the stator slot B302 are two stator slots 3 distributed with multi-layer flat wire conductors, with the center of the stator core 1 as the position reference, the stacking order of the multi-layer flat conductor wire in the stator slot A201 from the outside to the inside is the first layer of flat conductor wire 201, the second layer of flat conductor wire 202,... the nth layer of flat conductor wire 20n, and the stacking order in the stator slot B202 from the outside to the inside is the nth layer of flat conductor wire 20n,... the second layer of flat conductor wire 202, the first layer of flat conductor wire 201. The thickness of the flat conductor is 0.1 mm to 3 mm, and the width of the flat conductor line is not limited, as long as the electromagnetic design requirements are met.

[0040] Embodiment 3 is different from Embodiments 1 and 2 in that, in the entire stator structure, the middle part of the end connection section of some motor windings adopts a bending and giving way structure, and the middle part of the end connection section of some motor windings adopts a flipping and giving way structure. In this way, by combining the bending and giving way structures with the flipping and giving way structures, it is possible to effectively reduce the AC loss caused by the unequal motor paths and the loss caused by the motor circulating current, thereby improving the motor efficiency.

[0041] Embodiment 4 is different from Embodiments 1, 2, and 3 in that, in the entire stator structure, the middle of the end connection section of some motor windings adopts a bent-out structure, the middle of the end connection section at one end of some motor windings adopts a bent-out structure, and the middle of the end connection section at the other end adopts a flip-out structure. Assembling as needed can effectively improve the efficiency of the motor and increase the applicable scenarios of the stator structure.

[0042] Embodiment 5 is different from Embodiments 1, 2, 3, and 4 in that, in the entire stator structure, the middle of the end connection section of some motor windings adopts a flipping structure, the middle of the end connection section at one end of some motor windings adopts a bending structure, and the middle of the end connection section at the other end adopts a flipping structure. Assembling according to needs can effectively improve the efficiency of the motor and improve the applicable scenarios of the stator structure.

[0043] Embodiment 6 is different from Embodiments 1, 2, 3, 4, and 5 in that, in the entire stator structure, the middle of the end connection section of some motor windings adopts a bent-out structure, the middle of the end connection section of some motor windings adopts a flip-out structure, the middle of the end connection section at one end of some motor windings adopts a bent-out structure, and the middle of the end connection section at the other end adopts a flip-out structure. Through reasonable layout, the volume of the entire motor can be effectively reduced, the efficiency of the motor can be effectively improved, and the applicable scenarios of the stator structure can be improved.

[0044] Example 7, see Fig. 9 , Fig.10 as well as Fig.11 In the specific manufacturing process, the motor winding is arranged to form a continuous wave winding, a Hair-pin winding, an X-pin winding or an I-pin winding. The traditional continuous wave winding process has problems such as winding formation and difficulty in arrangement. This solution can simplify the difficulties of the continuous wave winding technology by reducing the hardness of the winding, so that this technology can be further applied to the drive motor industry.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Those skilled in the art should understand that those modifications or equivalent substitutions of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution should be included in the scope of the claims of the present invention.

Claims

1. A stator structure based on multi-layer flat wire windings, comprising a stator core and a plurality of motor windings, wherein a plurality of stator slots penetrating the two ends of the stator core along the circumferential direction of the inner wall of the stator core are provided; the motor winding comprises a plurality of multi-layer flat wire conductors, and the flat wire conductors are spaced apart and distributed in two stator slots; characterized in that: Each layer of flat wire conductors includes straight segments in two stator slots, one corresponding end of the straight segments in the two slots is connected through an end connecting segment located outside the stator slot, and the other end is connected to the corresponding end of the straight segments in the slots of two adjacent layers of flat wire conductors through the end connecting segment located outside the stator slot; the middle part of the end connecting segment has a bending yielding structure or a flipping switching structure.

2. A stator structure based on multi-layer flat wire windings according to claim 1, characterized in that: The straight sections in the two slots of the multi-layer flat wire conductor of the motor winding are arranged in parallel from the inside to the outside of the stator slot; the end connecting section also includes two connecting branch sections, which are formed by the straight section in the slot extending out of the stator slot and tilting toward the direction of the straight section in the other slot; the bent and yielding structure is an arc section bent in the direction away from the stator core, and its two ends are connected to the corresponding two connecting branch sections, and the projection of the arc section on a plane perpendicular to the axial centerline of the stator core is S-shaped, and the plane where the arc section is located is parallel to the axial centerline of the stator core, and the end connecting sections of the multi-layer flat wire conductor are also arranged in parallel from the inside to the outside of the stator slot.

3. The stator structure based on multi-layer flat wire winding according to claim 1, characterized in that: The straight sections in the slots on one side of the multi-layer flat wire conductor of the motor winding are arranged in parallel from the inside to the outside of the stator slot, and the straight sections in the slots on the other side are arranged in parallel from the outside to the inside of the stator slot; the end connecting section also includes two connecting branch sections, and the connecting branch sections are formed by the straight section in the slot extending out of the stator slot and then tilting and twisting toward the direction of the straight section in the other slot; the flip-over structure is an arc section bent in the direction away from the stator core as a whole, and the two arms of the arc section are twisted in opposite directions and connected to the corresponding two connecting branch sections, and the plane where the arc section is located is perpendicular to or intersecting with the axial centerline of the stator core, and the flip-over structure of the end connecting section of the multi-layer flat wire conductor is arranged in parallel from top to bottom.

4. A stator structure based on multi-layer flat wire windings according to claim 2 or 3, characterized in that: There is a distance between the bending yielding structure or the flipping shifting structure and the stator core, so that the end connecting section is V-shaped as a whole.

5. The stator structure based on multi-layer flat wire winding according to claim 1, characterized in that: An insulating layer structure is coated on the outer side of the flat wire conductor.

6. The stator structure based on multi-layer flat wire winding according to claim 1, characterized in that: The thickness of the flat wire conductor is 0.1 mm-3 mm.

7. The stator structure based on multi-layer flat wire winding according to claim 1, characterized in that: The motor windings are arranged to form continuous wave windings, Hair-pin windings, X-pin windings or I-pin windings.

8. The stator structure based on multi-layer flat wire winding according to claim 1, characterized in that: The middle part of the end connection section at one end of the motor winding adopts a bending-yielding structure, and the middle part of the end connection section at the other end adopts a flipping-yielding structure.

9. A stator structure based on multi-layer flat wire windings according to claim 1 or 8, characterized in that: The middle part of the end connecting section of some motor windings adopts a bending giving structure, and the middle part of the end connecting section of some motor windings adopts a flipping giving structure; or the middle part of the end connecting section of some motor windings adopts a bending giving structure, the middle part of the end connecting section at one end of some motor windings adopts a bending giving structure, and the middle part of the end connecting section at the other end adopts a flipping giving structure; or the middle part of the end connecting section of some motor windings adopts a flipping giving structure, the middle part of the end connecting section at one end of some motor windings adopts a bending giving structure, and the middle part of the end connecting section at the other end adopts a flipping giving structure; or the middle part of the end connecting section of some motor windings adopts a bending giving structure, the middle part of the end connecting section of some motor windings adopts a flipping giving structure, the middle part of the end connecting section at one end of some motor windings adopts a bending giving structure, and the middle part of the end connecting section at the other end adopts a flipping giving structure.

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