Tooth yoke splicing type stator core and motor thereof

Abstract

The invention discloses a tooth yoke splicing type stator core combining oriented silicon steel and non-oriented silicon steel and a motor with the same. The stator core comprises a stator tooth part, a stator yoke part and an insert. The stator teeth comprise main teeth and yoke teeth, the yoke teeth are distributed in the circumferential direction of the stator yoke part, the yoke teeth and the stator yoke part form an integrated structure, and the main teeth and the yoke teeth are in one-to-one correspondence in the radial direction; splicing teeth are arranged at the roots of the main teeth, splicing grooves are formed in the tops of the corresponding yoke teeth, and the splicing teeth and the splicing grooves are spliced in the radial direction. Caulking grooves are formed in the main teeth and the yoke teeth, and after the splicing teeth and the splicing grooves are spliced, the inserts can be embedded into the caulking grooves; the stator main teeth and the inserts are made of oriented silicon steel in the rolling direction, and the stator yoke part is made of non-oriented silicon steel. The stator main teeth adopt oriented silicon steel in the rolling direction, so that the problems of motor performance reduction and insufficient material utilization caused by magnetic anisotropy of oriented silicon steel adopted by a stator yoke part are solved; and meanwhile, the insert made of oriented silicon steel in the same direction as the stator main teeth is used as the reinforcing rib, so that the tooth yoke splicing structure can be well fixed and is not easy to deform, and the loss of the stator can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motor structures, and particularly to a stator core and a motor having the same. Background Art

[0002] The motor industry is accelerating its transformation towards high efficiency, lightweight, and miniaturization. Traditional cold-rolled non-oriented silicon steel, as a magnetic conductive material, is widely used in motor manufacturing. However, its performance and cooling capacity limit the further improvement of motor efficiency. To solve this problem, grain-oriented silicon steel with high magnetic induction and low iron loss is applied to motors. However, the magnetic conductive performance of grain-oriented silicon steel highly depends on the rolling direction. Once deviated, the performance will significantly decline. Due to the inconsistent magnetic circuit distribution in the stator teeth and stator yoke, directly replacing non-oriented silicon steel with grain-oriented silicon steel may lead to a decrease rather than an increase in motor performance. To apply grain-oriented silicon steel to rotating motors, a tooth-yoke separation structure must be adopted.

[0003] In the prior art, the patent number is: 202310624588.7, and the name is: A spliced stator and its manufacturing method, which discloses that both the stator teeth and yoke adopt grain-oriented silicon steel. By controlling the included angle of the tooth block axis, the flux deflection angle of the yoke is ensured, thereby maintaining the advantages of grain-oriented silicon steel. However, due to the stator slot number and size problems, the method of controlling the stator tooth included angle has poor versatility. Once the angle deviation is too large, the performance of grain-oriented silicon steel cannot be fully utilized, resulting in material waste and even affecting the motor performance. On the other hand, during the operation of the motor, the stator teeth will be affected by magnetic tensile force. For the tooth-yoke splicing part, the fastening and strength problems must be considered.

[0004] Therefore, the present invention proposes a tooth-yoke spliced stator core and its motor. Summary of the Invention

[0005] To solve the above technical problems, the purpose of the present invention is to provide a tooth-yoke spliced stator core structure combining grain-oriented silicon steel and non-oriented silicon steel, which can improve the torque performance of the motor, reduce the core loss, and at the same time, the splicing part can well fix the tooth-yoke splicing structure, is not easy to deform and can improve the magnetic circuit distribution.

[0006] To achieve the above purpose, the technical solution of the present invention is as follows:

[0007] A tooth-yoke spliced stator core structure includes: stator teeth, stator yoke, and inserts. The stator teeth are divided into main teeth and yoke teeth. The yoke teeth are distributed circumferentially along the stator yoke and form an integral structure with the stator yoke. The main teeth and yoke teeth correspond to each other radially. A splicing tooth is provided at the root of the main tooth, and a splicing groove is provided at the top of the corresponding yoke tooth. The splicing tooth and the splicing groove are spliced radially. Embedding grooves are provided inside both the main teeth and yoke teeth. After the splicing tooth and the splicing groove are spliced, the inserts can be embedded into the embedding grooves to reinforce the tooth-yoke splicing.

[0008] Both the main tooth part and the insert are made of grain-oriented electrical steel in the rolling direction, and the stator yoke is made of non-oriented electrical steel.

[0009] In the above technical solution, preferably, the shapes of the splicing teeth and the splicing grooves should be completely adapted to ensure that the end faces of the splicing teeth and the splicing grooves are completely fitted after splicing.

[0010] In this technical solution, by completely fitting the splicing teeth and the splicing grooves, the negative impact caused by the splicing air gap is avoided.

[0011] In the above technical solution, preferably, the ratio of the length of the main tooth part to the length of the yoke tooth part is greater than or equal to 2 and less than or equal to 3.

[0012] In this technical solution, by limiting the lengths of the main tooth part and the yoke tooth part, on the one hand, it can ensure that the main tooth part can give full play to the advantages of grain-oriented electrical steel, and on the other hand, it can ensure that the yoke tooth part has sufficient slot depth for embedding.

[0013] In the above technical solution, preferably, the ratio of the slot depth inside the main tooth to the slot depth inside the yoke tooth is greater than or equal to 2, and the slot depth of the yoke tooth part should not exceed the stator slot depth ( Figure 1 the U-shaped slot between adjacent yoke teeth on the stator).

[0014] In this technical solution, by limiting the slot depth of the yoke tooth part, it is ensured that the insert is located in the straight tooth part, and the problem of performance degradation of the insert made of grain-oriented electrical steel in the stator yoke due to magnetic circuit changes is avoided.

[0015] In the above technical solution, preferably, the shape of the insert is not fixed and may include structures such as "I" shape, "butterfly" shape, and "dumbbell" shape.

[0016] In the above technical solution, preferably, the insert and the slot should be in interference fit.

[0017] The present invention also provides a permanent magnet synchronous motor, and this permanent magnet synchronous motor adopts the above stator core structure.

[0018] The above technical solution of the present invention can achieve the following beneficial effects:

[0019] 1) By separating the stator teeth and yoke, the main tooth part is made of grain-oriented electrical steel in the rolling direction, and the yoke part is made of non-oriented electrical steel, avoiding the problems of performance reduction and insufficient material utilization of grain-oriented electrical steel in the yoke due to magnetic circuit direction changes; the characteristics of high magnetic induction and low iron loss of grain-oriented electrical steel are utilized in the main tooth part, significantly improving the motor output torque performance and reducing the stator core loss.

[0020] 2) By using inserts made of grain-oriented electrical steel in the rolling direction as stiffeners, on the one hand, the connection between the stator teeth and the stator yoke is strengthened, and on the other hand, the excellent properties of grain-oriented electrical steel are fully utilized, reducing the stator loss and improving the magnetic circuit distribution at the connection.

[0021] 3) The tooth yoke of the present invention adopts the form of splicing + inserts, providing double fixation of radial constraint and circumferential constraint, with high structural strength, which is beneficial to improving the performance of the motor.

[0022] 4) The stator tooth yoke of the present invention is separated, and different materials can be selected according to the characteristics of the inner and outer circles of the stator. For example, a material with better performance can be used for the outer circle; a material with better strength can be used for the inner circle, achieving performance improvement while improving economy and avoiding using the same material, resulting in higher costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of the stator core of the present invention;

[0024] Figure 2 is a schematic structural diagram of the main stator teeth of the present invention;

[0025] Figure 3 is a schematic structural diagram of the stator yoke of the present invention;

[0026] Figure 4 is Figure 3 a partial enlarged view of part A in

[0027] Figure 5 is a schematic structural diagram of the insert of the embodiment of the present invention;

[0028] Figure 6 is a schematic diagram of the magnetic conduction direction of grain-oriented electrical steel;

[0029] Figure 7 is the magnetic flux density distribution diagram and iron loss distribution diagram of the existing grain-oriented electrical steel;

[0030] Figure 8 is the stress nephogram of the tooth yoke splicing structure with and without inserts of the present invention under the influence of magnetic tensile force;

[0031] Figure 9 is the comparison curve of the losses of the main stator teeth with and without inserts of the present invention;

[0032] Figure 10 is the comparison curve of the torque performance of the tooth yoke splicing motor and the traditional permanent magnet synchronous motor of the embodiment of the present invention;

[0033] In the figure: 1. Stator tooth part; 2. Stator yoke part; 3. Insert; 4. Grain-oriented silicon steel; 11. Main tooth; 111. Spliced tooth; 112. Main tooth insertion groove; 12. Yoke tooth; 121. Splicing groove; 122. Yoke tooth insertion groove. Detailed implementation mode

[0034] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. In the drawings, for the sake of clarity, the dimensions of the structural areas may be enlarged or reduced, but the same reference numerals are used to denote the same components, and thus their descriptions will be omitted. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0035] The following will refer to Figures 1 to 6 Describe in detail the stator core structure of an embodiment of the present invention.

[0036] As Figure 1 and Figure 3 shown, according to the motor stator core structure of the embodiment of the present invention, it includes: a stator tooth part 1, a stator yoke part 2 and an insert 3.

[0037] The stator tooth part 1 can be divided into a main tooth 11 and a yoke tooth 12. The stator yoke part 2 includes a plurality of yoke teeth 12 distributed circumferentially. The number and position of the main teeth 11 correspond one-to-one with the yoke teeth 12 in the radial direction.

[0038] As Figure 2 shown, a spliced tooth 111 is provided at the bottom of the main tooth 11. The height of the spliced tooth 111 is h d1 , and the width is w 12 (the spliced tooth 111 has a convex-shaped structure), and a T-shaped insertion groove (main tooth internal insertion groove 112) is provided in the middle, and its depth is h 11 + h 12 , and the width is w 11 , and the height of the main tooth 11 is h1.

[0039] As Figure 4 shown, a splicing groove 121 is provided at the top of the yoke tooth 12. The depth of the splicing groove 121 is h d2 , and the width is w 22 (the splicing groove 121 has a concave-shaped structure), and similarly, a T-shaped insertion groove (yoke tooth internal insertion groove 122) is provided in the middle, and its depth is h 21 + h 22 , and the width is w 21 , and the height of the yoke tooth 12 is h2.

[0040] Specifically, the ratio of h1 to h2 should be greater than or equal to 2 and less than or equal to 3. Since the main tooth 11 is made of grain-oriented silicon steel, the value of h1 should be as large as possible to ensure that the main tooth 11 can fully utilize the advantages of grain-oriented silicon steel. However, sufficient dimensions of the yoke tooth 12 should be ensured for splicing and fixing.

[0041] Specifically, the sum of the depth of the splicing groove 121 and the depth of the internal embedding groove 122 of the yoke tooth should not exceed the height of the yoke tooth, that is, h d2 +h 21 +h 22 ≤h2. By restricting its depth, it can be ensured that the insert 3 is located inside the yoke tooth after being embedded. Since the insert 3 is made of grain-oriented silicon steel, if it is located at the changing place of the magnetic flux path, the characteristics of grain-oriented silicon steel cannot be fully utilized, which may deteriorate the performance of the connection.

[0042] Specifically, the main tooth 11 and the yoke tooth 12 are radially spliced through the splicing tooth 111 and the splicing groove 121. The shapes of the splicing tooth 111 and the splicing groove 121 should be completely adapted, and it is required that w 12 =w 22 ,h d1 =h d2 . During splicing, ensure that the splicing tooth 111 and the splicing groove 121 are completely fitted, which can avoid generating splicing air gaps during the cooperation process and having a negative impact on the performance of the motor.

[0043] Specifically, after the main tooth 11 and the yoke tooth 12 are spliced, an "I"-shaped embedding groove can be formed, and the insert 3 can be fixed after being embedded, as Figure 5 shown. The dimensions of the insert are w 11 =w 21 ,h 12 =h 22 ,h3=h 11 +h 21 +h d2 .

[0044] Specifically, the shapes of the internal embedding grooves of the main tooth 11 and the yoke tooth 12 are not fixed, and an "I"-shaped, "butterfly"-shaped, or "dumbbell"-shaped embedding groove can be formed after splicing; when the formed embedding groove shape is "butterfly"-shaped or "dumbbell"-shaped, the shape of the insert 3 corresponds to it, and the two are matched.

[0045] As Figure 6 shown, the vertical direction is the rolling direction of the grain-oriented silicon steel 4, the horizontal direction is the shearing direction of the grain-oriented silicon steel 4, and the manufacturing directions of the stator main tooth 11 and the insert 3 are the rolling direction, making full use of the excellent performance of the grain-oriented silicon steel in the rolling direction.

[0046] Specifically, grain-oriented electrical steel is a special type of electrical steel material. Compared with non-oriented electrical steel, it has the characteristics of high magnetic induction and low loss, and is mainly used to manufacture the iron cores of equipment such as transformers, reactors, and instrument transformers.

[0047] Figure 7 The magnetic flux density distribution map of the existing grain-oriented electrical steel ( Figure 7 part a in Figure 7 and the iron loss distribution map (

[0048] part b in

[0049] are given. Among them, the unit of magnetic flux density is T, the unit of iron loss is W / kg, and the 0° direction is the rolling direction.

[0050] Specifically, it can be seen that the performance of grain-oriented electrical steel has a high degree of orientation, that is, along the rolling direction, its magnetic permeability is high and the iron loss is low. Deviating from the rolling direction, its performance decreases significantly, and its performance is the worst in the shearing mode. During the operation of a rotating electrical machine, the direction of the magnetic flux will change continuously. If grain-oriented electrical steel is directly applied to a rotating electrical machine, due to the change in the direction of the magnetic flux, the performance of the electrical machine will deteriorate. Therefore, in a rotating electrical machine, applying grain-oriented electrical steel with the rolling direction to a structure where the magnetic circuit does not change can make full use of its characteristics and improve the performance of the electrical machine.

[0051] In this embodiment, only grain-oriented electrical steel is used for the main stator teeth 11 and the inserts 3, and the stator yoke 2 still uses traditional non-oriented electrical steel.

[0052] Figure 8 The stress nephograms of the tooth-yoke splicing structure with inserts (part a) in this embodiment and the tooth-yoke splicing structure without inserts in the prior art (part b) under the influence of magnetic tensile force are given, and the simulation conditions of both are the same.

[0053] It can be seen that under the same conditions, the maximum stress of the tooth-yoke splicing structure in this embodiment under the influence of magnetic tensile force is less than that of the tooth-yoke splicing structure without inserts. It can be seen that using inserts is beneficial to the fixation of the tooth-yoke splicing.

[0054] Figure 9 The comparison of the stator main tooth loss curves of the tooth-yoke splicing structure with inserts in this embodiment and the tooth-yoke splicing structure without inserts in the prior art within a stable period is given, and the simulation conditions of both are the same.

[0055] Specifically, under the same conditions, the loss of the stator main tooth part with inserts in this embodiment is 68 W, and the loss of the stator main tooth part without inserts is 75 W. It can be seen that using inserts with low iron loss is not only beneficial to the fixation of the tooth yoke splicing, but also has a reducing effect on the stator loss. In this embodiment, the loss of the stator main tooth part is reduced by approximately 10%.

[0056] Figure 10 The comparison of the output torque performance of three motors is given, namely, the motor with tooth yoke splicing using grain-oriented silicon steel and non-grain-oriented silicon steel combination for the stator of the present invention, the motor with non-grain-oriented silicon steel for both stator tooth yokes, and the motor with grain-oriented silicon steel for both stator tooth yokes. The other structures of the three motors are the same except for the stator, and this result is obtained under the same simulation conditions. It can be seen that the performance of the motor with grain-oriented silicon steel for the stator teeth and non-grain-oriented silicon steel for the yoke is better than that of the motor with grain-oriented silicon steel for both stator tooth yokes. However, after using grain-oriented silicon steel for the yoke, due to the inconsistent magnetic circuit distribution between the stator teeth and the stator yoke, the output torque performance of the motor decreases instead of increasing.

[0057] The present invention increases the structural strength of the tooth yoke separated stator through the form of splicing + inserts, and at the same time matches different materials, that is, using grain-oriented silicon steel for the main teeth and inserts, and non-grain-oriented silicon steel for the stator yoke, reducing the core loss and improving the motor torque; it has outstanding progress compared with the prior art.

[0058] The above are only the preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention. For those skilled in the art, it should be able to realize that all the equivalent replacements and obvious changes made by using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A tooth-yoke spliced stator core, characterized in that It includes a stator yoke, stator teeth and inserts. The stator teeth portion includes main teeth and yoke teeth, and a plurality of yoke teeth are arranged circumferentially along the stator yoke. The main teeth correspond to the yoke teeth one by one, and the main teeth and the yoke teeth are radially spliced to achieve radial positioning and circumferential positioning between the yoke teeth and the main teeth. The inserts are embedded between the main teeth and the yoke teeth to achieve radial limitation and circumferential limitation between the yoke teeth and the main teeth. Both the main teeth and the inserts are made of grain-oriented electrical steel in the rolling direction, and the stator yoke is made of non-oriented electrical steel.

2. The segmented stator core according to claim 1, wherein Splicing teeth are provided at the bottom of the main teeth, and splicing grooves are provided at the top of the yoke teeth. The splicing teeth and the splicing grooves cooperate to achieve the radial splicing of the main teeth and the yoke teeth.

3. The segmented stator core according to claim 1, wherein Main tooth internal embedding grooves are provided inside the main teeth, and yoke tooth internal embedding grooves are provided inside the yoke teeth. After the main teeth and the yoke teeth are spliced through the splicing teeth and the splicing grooves, the inserts are embedded into the embedding grooves of both.

4. A tooth-yoke spliced stator core according to claim 1, wherein A plurality of the yoke teeth and the stator yoke are of an integral structure.

5. The segmented stator core according to claim 1, characterized in that, The shapes and sizes of the splicing teeth and the splicing grooves are matched to ensure that the end faces of the splicing teeth are completely fitted with the end faces of the splicing grooves after splicing.

6. The segmented stator core according to claim 1, characterized in that, The ratio of the depth of the main tooth internal embedding groove to the depth of the yoke tooth internal embedding groove is greater than or equal to 2, and the depth of the yoke tooth internal embedding groove does not exceed the depth of the stator slot.

7. The segmented stator core according to claim 1, wherein, The ratio of the length of the main teeth to the length of the yoke teeth is greater than or equal to 2 and less than or equal to 3.

8. A yoke-spliced stator core according to claim 1, characterized in that The structural shape of the inserts is I-shaped, butterfly-shaped or dumbbell-shaped.

9. A motor, comprising a stator core, characterized in that, The stator core is the stator core according to any one of claims 1-8.

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