WO2022213695A1 - Stator assembly and winding method therefor, and double-rotor motor - Google Patents

Abstract

The present application provides a stator assembly and a winding method therefor, and a double-rotor motor. The stator assembly comprises a stator core (1) and a stator winding. The stator core (1) comprises an inner side stator slot (2), an inner side stator tooth (3), a stator yoke part (4), an outer side stator slot (5) and an outer side stator tooth (6). The stator winding comprises an inner winding (7) embedded in the inner side stator slot (2) and an outer winding (8) embedded in the outer side stator slot (5). According to the stator assembly of the present application, the utilization rate of winding can be improved, and the output torque and power density of a motor is improved.

Description

Stator assembly and its winding method, dual rotor motor

Related applications

This application claims the priority of the Chinese patent application filed on April 08, 2021, with the application number of 202110375878.3 and the title of "Stator Assembly and Its Winding Method, Dual-Rotor Motor", which is hereby incorporated by reference in its entirety.

technical field

The present application relates to the technical field of electric motors, and in particular, to a stator assembly and its winding method, and a dual-rotor motor.

Background technique

As the country vigorously promotes industrial upgrading, the motor field will continue to develop towards high speed and miniaturization. The resulting motor power density and loss density will continue to rise, and the heat generation of the motor windings, especially the end windings, will further increase.

The use of the back-wound winding form can effectively reduce the size of the motor winding end, especially the outlet end, and the end resistance becomes smaller, and the heat generation can be effectively reduced. However, under the condition of the same number of turns, the back-wound winding requires more stator slot space. In order to ensure that the magnetic field distribution of the motor is not over-saturated and the output torque remains unchanged under the same current, the size of the stator core of the motor will become larger, and the power of the motor will be larger. Density will drop.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present application is to provide a stator assembly and its winding method, and a dual-rotor motor, which can improve the utilization rate of the windings and improve the output torque and power density of the motor.

In order to solve the above problems, the present application provides a stator assembly, including a stator iron core and a stator winding, the stator iron core includes inner stator slots, inner stator teeth, stator yokes, outer stator slots and outer stator teeth, and the stator windings include embedded stator The inner layer windings in the inner stator slots and the outer layer windings embedded in the outer stator slots.

In one of the embodiments, the inner diameter of the stator core is R2, the outer diameter is R1, the inner diameter of the stator yoke is R4, the outer diameter is R3, the width of the inner slot of the inner stator slot is L, and the width of a single inner stator slot is L. The cross-sectional area is S, the size coefficient of the inner diameter of the stator yoke is λ ₁ , and the size coefficient of the outer diameter of the stator yoke is λ ₂ , where:

1.7≤λ ₁ ≤2.2, 0.34≤λ ₂ ≤0.61.

In one of the embodiments, the radial depth of the inner stator slots is more than twice the radial depth of the outer stator slots.

In one of the embodiments, on a section perpendicular to the central axis of the stator core, the side edge of the outer stator slot is located on the extension line of the side edge of the inner stator slot on the side.

In one of the embodiments, the cross-sectional area of a single inner stator slot is S, and the cross-sectional area of a single outer stator slot is S1, and S<S1.

In one of the embodiments, 0.7≤S/S1≤0.9.

According to one aspect of the present application, a dual-rotor motor is provided, including a stator assembly, the stator assembly being the above-mentioned stator assembly.

In one of the embodiments, the dual-rotor motor further includes a first rotor and a second rotor, the first rotor is located on the inner peripheral side of the inner stator teeth, and the second rotor is located on the outer peripheral side of the outer stator teeth.

In one of the embodiments, the first rotor is an embedded or surface-mounted magnetic steel structure, the outer casing of the first rotor is provided with a first sheath, and the first sheath is made of a non-magnetic conductive material; and/or, the second The rotor is an embedded or surface-mounted magnetic steel structure, the second rotor is internally sleeved with a second sheath, and the second sheath is made of non-magnetic conductive material.

According to an aspect of the present application, a method for winding the above stator assembly is provided, comprising:

Winding the stator core so that a single coil is wound in the radially corresponding inner stator slot and outer stator slot at the same time;

The coils are wound according to the phases to form the inner layer winding embedded in the inner stator slot and the outer layer winding embedded in the outer stator slot.

In one of the embodiments, the winding sequence of coil winding by phase is A+→C-→B+→A-→C+→B-, and the winding of phase A+ is completed first, and then the winding of phase C- is completed. ,And so on.

In one of the embodiments, the winding process of the A+ phase is as follows:

One end of the winding is embedded from the front of the No. 1 inner stator slot on the edge of the A+ phase side, crosses the stator yoke and enters the No. 1 outer stator slot corresponding to the inner stator slot from the back;

After completing the winding of the No. 1 inner stator slot and the No. 1 outer stator slot, make the windings cross the stator yoke diagonally, enter the No. 2 inner stator slot adjacent to the No. 1 inner stator slot from the front, and perform No. 2 The coils of the inner stator slot and the second outer stator slot are wound; then enter other stator slots in turn to complete the A+ phase winding off-line.

The stator assembly provided by this application includes a stator iron core and a stator winding, the stator iron core includes inner stator slots, inner stator teeth, stator yokes, outer stator slots and outer stator teeth, and the stator windings include inner stator slots embedded in the inner stator slots. The inner layer winding and the outer layer winding embedded in the outer stator slot. The stator winding of the stator assembly includes an inner layer winding embedded in the inner stator slot and an outer layer winding embedded in the outer stator slot, and the same coil is wound in the inner stator slot and the outer stator slot at the same time. The stator magnetic field formed by the inner winding in the inner stator slot interacts with the rotor magnetic field inside the inner stator slot to generate electromagnetic torque. The interaction of the magnetic field of the rotor generates electromagnetic torque, so that both the inner winding and the outer winding can be fully utilized, which can improve the utilization rate of the stator winding, thereby improving the output torque, power and power density of the motor.

Description of drawings

FIG. 1 is a schematic structural diagram of a dual-rotor motor according to an embodiment of the present application.

FIG. 2 is a schematic structural diagram of a stator assembly of a dual-rotor motor according to an embodiment of the present application.

FIG. 3 is a schematic diagram of a winding structure of a stator core of a dual-rotor motor according to an embodiment of the present application.

FIG. 4 is a structural diagram of a parallel magnetic circuit of a dual-rotor motor according to an embodiment of the present application.

FIG. 5 is a comparison diagram of the output torque of the single-rotor back-wound motor in the conventional technology and the dual-rotor back-wound motor of the present application.

FIG. 6 is a dimension relationship diagram of a stator core of a dual-rotor motor according to an embodiment of the present application.

FIG. 7 is a flowchart of a method for winding a stator assembly of a dual-rotor motor according to an embodiment of the present application.

Detailed ways

1 to 6 , according to an embodiment of the present application, the stator assembly includes a stator core 1 and a stator winding, and the stator core 1 includes an inner stator slot 2 , an inner stator tooth 3 , a stator yoke 4 , and an outer stator Slot 5 and outer stator teeth 6. The stator windings include inner layer windings 7 embedded in inner stator slots 2 and outer layer windings 8 embedded in outer stator slots 5 .

The stator winding of the stator assembly includes an inner layer winding 7 embedded in the inner stator slot 2 and an outer layer winding 8 embedded in the outer stator slot 5 , and the same coil is wound around the inner stator slot 2 and the outer stator slot 5 at the same time. The inner stator slot 2 is formed between two adjacent inner stator teeth 3 , and the outer stator slot 5 is formed between two adjacent outer stator teeth 6 . Therefore, electromagnetic torque can be generated by the interaction between the stator magnetic field formed by the inner winding 7 located in the inner stator slot 2 and the rotor magnetic field inside the inner stator slot 2; The formed stator magnetic field interacts with the rotor magnetic field outside the outer stator slot 5 to generate electromagnetic torque, so that both the inner layer winding 7 and the outer layer winding 8 can be fully utilized, so as to improve the utilization rate of the stator winding, thereby improving the output of the motor torque, power and power density, and can also effectively reduce the end temperature of the motor winding.

In one embodiment, the inner diameter of the stator core 1 is R2, and the outer diameter is R1; the inner diameter of the stator yoke 4 is R4, and the outer diameter is R3; the inner slot width of the inner stator slot 2 is L; a single inner stator slot The cross-sectional area of 2 is S; the inner diameter dimension factor of the stator yoke 4 is λ ₁ ; the outer diameter dimension factor of the stator yoke 4 is λ ₂ , where:

1.7≤λ ₁ ≤2.2, 0.34≤λ ₂ ≤0.61.

In this embodiment, after R1 and R2 are determined, the inner diameter R4 and outer diameter R3 of the stator yoke 4 can be determined by the inner slot width of the inner stator slot 2 . Therefore, in the design process of the stator core 1 , the width L of the inner slot can be related to the inner diameter R4 and outer diameter R3 of the stator yoke 4. Under the condition that the cross-sectional area S of a single inner stator slot 2 is constant, by adjusting the inner slot width L of the inner stator slot 2 , the values of R3 and R4 can be adjusted accordingly, so that the inner stator slot 2 has a good slot full rate, and at the same time can ensure the area of the stator yoke, so that both the inner winding 7 and the outer winding 8 can have sufficient magnetic flux flow area, avoiding the phenomenon of magnetic circuit oversaturation, and at the same time, it can effectively improve the power density and improve the output torque of the motor.

In one embodiment, the radial depth of the inner stator slot 2 is more than twice the radial depth of the outer stator slot 5, so that the depth of the inner stator slot 2 can be increased, and the width L of the inner slot can be reduced, thereby further improving the Slot full rate, improve copper wire utilization.

In one embodiment, on a section perpendicular to the central axis of the stator core 1, the side of the outer stator slot 5 is located on the extension line of the side of the inner stator slot 2 on the side, so that the inner stator slot 2 and the outer stator are There is a better structural correspondence between the slots 5, which can reduce the design difficulty of the inner stator slot 2 and the outer stator slot 5, and it is easier to determine the structure size of the outer stator slot 5 according to the structure size of the inner stator slot 2. In order to improve the design efficiency.

In one embodiment, the cross-sectional area of a single inner stator slot 2 is S, and the cross-sectional area of a single outer stator slot 5 is S1, where S<S1.

In one embodiment, 0.7≤S/S1≤0.9.

The stator core is made of magnetically conductive material, such as silicon steel sheet, amorphous alloy or soft magnetic material.

Referring to FIGS. 1 to 5 in combination, according to an embodiment of the present application, a dual-rotor motor includes a stator assembly, and the stator assembly is the above-mentioned stator assembly.

The dual-rotor motor further includes a first rotor 9 and a second rotor 10 . The first rotor 9 is located on the inner peripheral side of the inner stator teeth 3 , and the second rotor 10 is located on the outer peripheral side of the outer stator teeth 6 .

The first rotor 9 is an embedded or surface-mounted magnetic steel structure, specifically a solid structure or a ring structure. The first rotor 9 is covered with a first sheath 11, and the first sheath 11 is made of a non-magnetic conductive material. The first rotor 9 may have an axial segmented structure or a circumferentially segmented structure. The first sheath 11 is, for example, stainless steel or high strength alloy material or carbon fiber.

The second rotor 10 is an embedded or surface-mounted magnetic steel structure, and may be a solid structure or a ring structure. The second rotor 10 is internally sheathed with a second sheath 12, and the second sheath 12 is made of a non-magnetically conductive material. The second rotor 10 can be an axial segmented structure or a circumferentially segmented structure, and the second sheath 12 is, for example, stainless steel or high-strength alloy material or carbon fiber.

There is an interference fit between the first rotor 9 and the first sheath 11 , and the specific amount of interference is determined by the rotational speed of the motor. There is also an interference fit between the second rotor 10 and the second sheath 12, and the amount of the interference is determined by the rotational speed of the motor.

Referring to FIG. 4 , in the embodiment of the present application, the dual-rotor motor adopts a back-wound winding structure, so that the inner layer winding 7 can cooperate with the first rotor 9 to form a magnetic circuit structure, so that the The stator magnetic field interacts with the rotor magnetic field generated by the first rotor 9 to generate electromagnetic torque; the outer winding 8 can cooperate with the second rotor 10 to form a magnetic circuit structure, so that the stator magnetic field generated by the outer winding 8 and the second rotor The rotor magnetic field generated by the rotor 10 interacts to generate electromagnetic torque, so that both the inner winding 7 and the outer winding 8 of the back wound winding can be fully utilized, thereby improving the output torque, power and power density of the motor.

Referring to FIG. 5 , the output torques of the single inner-layer rotor back-wound motor in the conventional technology and the double-rotor back-wound motor of the embodiment of the present application under the same current are given. It can be clearly seen from FIG. 5 It can be seen that after using the dual-rotor motor of the embodiment of the present application, compared with the single-rotor motor in the traditional technology, the output torque is increased by 208%, and the motor power density is also increased by 208% at the same speed. The boost is huge.

Referring to FIG. 7 , according to an embodiment of the present application, the above-mentioned method for winding the stator assembly includes: winding the stator core 1 , so that a single coil is simultaneously wound on the inner stator slot 2 and the outer side corresponding to the radial direction. In the stator slot 5; the coils are wound according to the phases to form the inner layer winding 7 embedded in the inner stator slot 2 and the outer layer winding 8 embedded in the outer stator slot 5.

The winding sequence of coil winding by phase is A+→C-→B+→A-→C+→B-, first complete the winding of A+ phase, then complete the winding of C- phase, and so on.

As shown in Figure 3, the winding process of the A+ phase is as follows: one end of the winding is inserted from the front side of the No. 1 inner stator slot ① on the edge of the A+ phase side, and then enters the No. 1 corresponding to the inner stator slot from the back after crossing the stator yoke Inside the outer stator slot ②; after completing the winding of the No. 1 inner stator slot ① and the No. 1 outer stator slot ②, make the winding obliquely cross the stator yoke 4, and enter from the front into the adjacent No. 1 inner stator slot ①. In the No. 2 inner stator slot ③, the coils of the No. 2 inner stator slot ③ and the No. 2 outer stator slot ④ are wound; then enter the No. ⑤, ⑥, ⑦, ⑧ stator slots in turn to complete the A+ phase winding off-line. The winding mode of the other phase windings is the same as that of A+, thus completing the winding off of the back-wound winding.

The front side here refers to the end face where the winding incoming side of the inner stator slot No. 1 is located. The oblique span from the stator slot No. 1 to the stator slot No. 2 refers to crossing the end face of the stator yoke 4 from the front of the outer stator slot No. 1 , and enter the No. 2 inner stator slot from the front for winding.

The winding method of the stator assembly of the present application adopts a single set of windings to simultaneously wind the inner layer winding 7 and the outer layer winding 8 to realize the winding of the back-wound winding. The structure is simple, the winding is convenient, and the winding efficiency can be improved. Effectively reduce winding waste and improve winding utilization.

It can be easily understood by those skilled in the art that, on the premise of no conflict, the above advantageous manners can be freely combined and superimposed.

The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. Inside. The above are only the preferred embodiments of the present application. It should be pointed out that for those skilled in the art, without departing from the technical principles of the present application, several improvements and modifications can also be made, and these improvements and modifications should also be It is regarded as the protection scope of this application.

Claims (12)

1. A stator assembly, comprising a stator iron core (1) and a stator winding, the stator iron core (1) comprising an inner stator slot (2), an inner stator tooth (3), a stator yoke (4), an outer stator slot ( 5) and outer stator teeth (6), the stator windings include an inner layer winding (7) embedded in the inner stator slot (2) and an outer layer embedded in the outer stator slot (5) winding (8).
2. The stator assembly according to claim 1, wherein the inner diameter of the stator core (1) is R2, the outer diameter is R1, the inner diameter of the stator yoke (4) is R4, the outer diameter is R3, the The inner slot width of the inner stator slot (2) is L, the cross-sectional area of a single inner stator slot (2) is S, the inner diameter dimension coefficient of the stator yoke (4) is λ ₁ , the stator yoke The outer diameter dimension factor of section (4) is λ ₂ , where:

   

   

   1.7≤λ ₁ ≤2.2, 0.34≤λ ₂ ≤0.61.
3. The stator assembly of claim 1, wherein the radial depth of the inner stator slots (2) is more than twice the radial depth of the outer stator slots (5).
4. The stator assembly according to claim 1, wherein, on a cross section perpendicular to the central axis of the stator core (1), the sides of the outer stator slots (5) are located on the inner stator slots (2). ) on the side extension of that side.
5. The stator assembly according to claim 1, wherein the cross-sectional area of a single said inner stator slot (2) is S, and the cross-sectional area of a single said outer stator slot (5) is S1, S<S1.
6. The stator assembly of claim 5, wherein 0.7≤S/S1≤0.9.
7. A dual-rotor electric machine comprising the stator assembly of any one of claims 1 to 6.
8. The dual-rotor motor according to claim 7, wherein the dual-rotor motor further comprises a first rotor (9) and a second rotor (10), the first rotor (9) being located on the inner stator teeth (3) ), the second rotor (10) is located on the outer peripheral side of the outer stator teeth (6).
9. The dual-rotor motor according to claim 8, wherein the first rotor (9) is an embedded or surface-mounted magnetic steel structure, and a first sheath (11) is provided on the outer layer of the first rotor (9) , the first sheath (11) is made of non-magnetic conductive material; and/or, the second rotor (10) is an embedded or surface-mounted magnetic steel structure, and the second rotor (10) The sleeve is provided with a second sheath (12), and the second sheath (12) is made of non-magnetic conductive material.
10. A winding method for the stator assembly of any one of claims 1 to 6, comprising:

    Winding the stator core (1), so that a single coil is simultaneously wound in the radially corresponding inner stator slot (2) and outer stator slot (5);

    The coils are wound according to the phases to form the inner layer winding (7) embedded in the inner stator slot (2) and the outer layer winding (8) embedded in the outer stator slot (5).
11. The winding method according to claim 10, wherein the winding sequence of coil winding by phase is A+→C-→B+→A-→C+→B-, and the winding of phase A+ is completed first, and then the winding of phase A+ is completed. C-phase winding, and so on.
12. The winding method according to claim 11, wherein the winding process of the A+ phase is as follows:

    One end of the winding is embedded from the front of the No. 1 inner stator slot on the edge of the A+ phase side, crosses the stator yoke and enters the No. 1 outer stator slot corresponding to the inner stator slot from the back;

    After completing the winding of the No. 1 inner stator slot and the No. 1 outer stator slot, make the windings cross the stator yoke diagonally, enter the No. 2 inner stator slot adjacent to the No. 1 inner stator slot from the front, and perform No. 2 The coils of the inner stator slot and the second outer stator slot are wound; then enter other stator slots in turn to complete the A+ phase winding off-line.

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