A stator core structure of a gear-yoke separated motor and its design and manufacturing method

Abstract

The present invention discloses a stator core structure of a tooth-yoke separation type motor and a design and manufacturing method thereof. The stator core structure comprises a yoke core and a tooth core. The inner wall of the yoke core is provided with a slot corresponding to the tooth. The tooth core is formed by stacking two different core laminations. The tooth top is fixed with a connecting piece to fix all the tooth cores together. The convex structure of the tooth root is precisely matched with the shape of the yoke slot. The design method of the present invention ensures mechanical strength and optimizes its torque performance by electromagnetic-stress coupling simulation and multi-objective optimization. The present invention improves the utilization rate of materials by a manufacturing method of tooth rotation dislocation, and avoids the slit affecting the tight connection at the slot. The tooth-yoke separation structure of the present invention has high stator mechanical strength, is easy to wind, and can realize flat wire coil assembly, which is beneficial to improving the slot fill rate, and can effectively weaken the leakage magnetic field and harmonics of the motor, reduce torque fluctuations, and improve the efficiency and performance of the motor.

Description

Technical Field

[0001] The invention belongs to the technical field of motors, and in particular relates to a stator core structure of a gear-yoke separated motor and a design and manufacturing method thereof. Background Art

[0002] High power density permanent magnet motors have higher requirements for the slot fill rate and core structure of the motor. The tooth part and yoke part of the traditional stator core are integrated. Due to the limitation of slot space, the winding wire embedding process is complicated, the slot fill rate is low, and the wire embedding process is easy to cause insulation damage to the coil, and it is difficult to realize the application of concentrated winding flat wire coils. Although there are some tooth-yoke separated stator core structures, such as the Chinese patent application with publication number CN211151640U, which provides a tooth-yoke separated motor stator core, it is mainly composed of several stator teeth and yoke parts separated from each other. The fixation of the stator teeth mainly depends on the close fit of the tooth yoke connection part, and the mechanical strength is obviously low. When the motor is running, it is easy to generate vibration at the connection point of the tooth yoke under the action of torque, and the motor has low reliability and short service life. For example, the literature [Xu Shibo, Tian Baozhi, Ma Deji, et al. Study on the influence of yoke interference fit on the performance of spliced ​​motors [J]. Electrical Steel, 2024, 6(3):26-30] proposed a motor stator with a sun tooth structure. However, this overall stator tooth structure can only adopt a closed slot structure, which increases the leakage flux in the stator, resulting in a decrease in the power factor and performance of the motor.

[0003] In addition, when the stator core is processed by wire cutting, due to the influence of factors such as the electrode wire diameter and the working voltage, a certain size loss will occur during the process, and a cutting seam of 0.1~0.3mm will be generated on the cutting surface, making it impossible to separate the yoke and then tightly assemble them. If the corresponding slot structure of the stator yoke and the tooth is cut at the same position, there will be a gap at the connection between the two, resulting in a reduction in mechanical strength; one solution is to cut a yoke and tooth that meet the tolerance from two pieces of material, but this cutting method will greatly reduce the utilization rate of materials. Summary of the invention

[0004] In view of the above, the present invention provides a yoke-separated motor stator core structure and a design and manufacturing method thereof. The purpose of adopting the yoke-separated structure in the stator core is to reduce the difficulty of winding embedding, while improving the slot fill rate and the efficiency and performance of the motor. It has high stator mechanical strength, is easy to wind and can realize flat wire coil assembly, can effectively weaken the leakage magnetic field and harmonics of the motor, and reduce torque fluctuations.

[0005] A tooth-yoke separated motor stator core structure comprises an annular yoke core and a tooth core, wherein the inner wall of the yoke core is provided with a plurality of slots along the circumferential direction, and the stator tooth roots of the tooth core are adapted to the slot shapes; the tooth core is formed by stacking two types of tooth laminations a and b, wherein the tooth lamination a is a mutually independent block tooth structure, and adjacent teeth are not connected; the tooth lamination b is an integral tooth structure, and adjacent teeth are connected at the tooth boot, and all teeth are connected to each other along the circumferential direction to form a sun tooth shape.

[0006] Furthermore, the lamination arrangement of the tooth core adopts two lamination modules A and B arranged alternately along the axial direction, the lamination module A is formed by stacking multiple tooth laminations a, and the lamination module B is formed by stacking multiple tooth laminations b, and the number of laminations of lamination modules A and B is determined by finite element simulation. Lamination module A can reduce the leakage magnetic field at the slot to improve the motor efficiency; lamination module B can play a role in enhancing the mechanical strength of the stator core, and by adjusting the proportion and combination arrangement of the two laminations, the optimal solution between the mechanical strength and the reduction of leakage magnetic field can be achieved; at the same time, the connection between the tooth lamination b and the tooth shoe can also play a role in modulating the air gap magnetic field, reducing the harmonic magnetic field, thereby reducing torque fluctuations and motor losses.

[0007] Furthermore, the slot of the yoke core and the stator tooth root of the tooth core are connected to each other by a mortise and tenon structure, and the shape of the slot can be dovetail, T-shaped or circular, etc., preferably dovetail.

[0008] Furthermore, the yoke core is formed by stacking yoke laminations, the thickness of the tooth lamination a or b is the same as the thickness of the yoke lamination, and the sum of the number of tooth laminations a and b is the same as the number of yoke laminations.

[0009] Furthermore, the stator slots formed by splicing the yoke core and the tooth core are flat-bottomed slots, and have both semi-closed slot and closed slot structures.

[0010] The stator core structure of the motor of the present invention can be separated into two parts: a stator yoke and a tooth part. The purpose of adopting the tooth yoke separation structure is to reduce the difficulty of winding embedding, while improving the slot fill rate and motor performance; the stator yoke is vertically connected to the tooth part, which is convenient for the winding or assembly of the concentrated flat wire winding; the customized tooth part is formed by a connecting piece formed by the closed opening of the tooth top position of some silicon steel sheets to fix all the tooth cores together, so that the stator has a higher mechanical strength while reducing the leakage magnetic field at the tooth shoe connection, and through the combined lamination of the two core thicknesses, it plays a role in reducing the air gap harmonic magnetic field, thereby effectively improving the efficiency and performance of the tooth yoke separation motor; the structure adopts a rotational offset processing method to avoid the size loss caused by cutting the corresponding tooth position of the yoke, achieve close fit between the tooth part and the yoke, and can significantly improve the utilization rate of the material.

[0011] The design method of the stator core structure of the gear-yoke separation motor of the present invention comprises the following steps:

[0012] (1) Determine the minimum lamination ratio η of the tooth lamination b in the tooth core through mechanical strength simulation, so that the strength of the tooth shoe connection meets the design requirements;

[0013] (2) Through two-dimensional electromagnetic simulation, the average torque and torque fluctuation performance of the motor under different configuration parameters (including the number of stacking modules A and B and the number of stacking sheets) of the two tooth stacking sheets are compared to select the optimal configuration parameters to obtain a preliminary design scheme and perform simulation verification;

[0014] (3) Based on the preliminary design scheme, the relationship curve of the influence of different slot widths, tooth shoulder heights, tooth widths, slot depths, stator inner diameters, and connection shapes on torque performance is obtained through multi-objective optimization. The parameters that have a greater impact on the motor torque performance are selected as optimization variables, thereby further optimizing the preliminary design scheme.

[0015] (4) Perform mechanical strength check on the optimized design to ensure that the mechanical strength of the stator meets the design requirements, thereby obtaining the final design of the stator core structure of the yoke-separated motor.

[0016] Furthermore, the minimum lamination ratio η=(n+1) / (2n+1), where n is the number of lamination modules A.

[0017] Furthermore, in the simulation verification process of the preliminary design scheme in step (2), the material magnetic permeability and the stacking coefficient at the slot connection are first modified to simulate the special structure caused by the alternating arrangement of the two types of tooth laminations in a two-dimensional simulation. After the preliminary design scheme is determined on this basis, a three-dimensional simulation verification is performed to determine the specific combination arrangement of the two types of tooth laminations in the axial direction, thereby shortening the time consumed by the simulation.

[0018] The above design method uses electromagnetic-stress coupling simulation and multi-objective optimization to ensure the mechanical strength of the motor while optimizing the torque performance of the motor and improving the efficiency of the yoke-separated stator motor.

[0019] The manufacturing method of the stator core structure of the tooth-yoke separated motor of the present invention is specifically as follows: when performing the cutting operation, the stator teeth are rotated by a certain angle by a rotational dislocation processing method so that the tooth root corresponds to the position of the bottom of the stator yoke slot, and the tooth laminations and the yoke laminations are cut on the same silicon steel sheet; when laminating the tooth core, the two tooth laminations are arranged according to the optimal configuration parameters determined by finite element simulation and the tooth roots, tooth bodies and tooth tops of the two tooth laminations are completely overlapped, and then they are laminated, bonded and welded to form, and the adjacent two teeth are connected by the tooth boots of the tooth lamination b; when assembling, the connection position of the stator tooth root and the stator yoke is aligned (to avoid the size loss caused by cutting at the corresponding tooth position of the yoke, and to achieve the close fit of the tooth and the yoke), so that the yoke core and the tooth core are spliced ​​and formed by the mortise and tenon structure, and finally the coil winding is wound on the stator teeth. Since the yoke and the tooth are cut from a piece of iron core, there is no matching gap between the connecting surfaces of the tooth and the yoke due to cutting and separation during assembly, and the contact surface can be further trimmed to achieve a higher surface finish.

[0020] The material used for cutting the stator tooth core laminations is the discarded part located inside the yoke ring when the stator yoke core laminations were originally cut; when cutting the stator teeth, the yoke is not cut at the corresponding tooth position, but it is rotated at a certain angle and the stator tooth laminations are cut at the corresponding slot position of the material; the purpose of adopting this cutting method is to make full use of the discarded part inside the yoke ring when cutting the yoke and improve the utilization rate of materials.

[0021] When cutting, the teeth are not cut directly at the corresponding tooth position of the yoke ring, because there will be dimensional loss in cutting. Direct cutting will cause the convex or concave part on one side of the slot to be too small or too large, resulting in a certain gap when the two sides are connected, making it impossible to achieve a tight or interference fit in assembly. Therefore, it is rotated a certain angle and the purpose of cutting from the slot position is to utilize the larger space at the corresponding position of the slot so that the convex or concave parts of the slot at the tooth root and the yoke can be cut separately.

[0022] In order to improve the processing and assembly accuracy and material utilization rate, the above-mentioned manufacturing method is proposed to avoid the gap between the mating contact surfaces caused by wire cutting or other processing methods, which can not only improve the material utilization rate, but also avoid the wire cutting seam affecting the tight connection at the slot.

[0023] In summary, the present invention has the following beneficial technical effects:

[0024] 1. The present invention combines the advantages of the integral tooth and block tooth structures of the tooth-yoke separation motor, reduces magnetic leakage at the slots and improves motor efficiency while ensuring the mechanical strength of the stator core.

[0025] 2. The tooth shoe connection of the present invention can modulate the magnetic field, reduce the harmonic magnetic field, and reduce the torque fluctuation and loss of the motor.

[0026] 3. The stator core of the present invention is formed by stacking the above-mentioned yoke-separated core laminations, which has the advantages of a yoke-separated motor, is easy to wind, reduces the risk of copper wire damage during winding, and can achieve a high slot fill rate arrangement of the winding.

[0027] 4. The motor stator core design method of the present invention can optimize the torque performance of the motor while ensuring the mechanical strength of the motor through electromagnetic-stress coupling simulation and multi-objective optimization, thereby improving the efficiency of the yoke-separated stator motor.

[0028] 5. The motor stator core design method of the present invention can effectively reduce the time consumed in the design of the motor electromagnetic scheme. Due to the combined arrangement of the two types of laminations, the slot positions of the motor stator have an uneven structure in the axial direction. Special settings are made at the slots to achieve a more accurate simulation of this type of special structure in two-dimensional simulation, which can effectively avoid the time consumption caused by the extensive use of three-dimensional simulation in the design process.

[0029] 6. The motor stator core manufacturing method of the present invention can simultaneously process the stator yoke and tooth structure on the same square or round sheet, and ensure the close fit of the connection between the two, effectively improve the utilization rate of materials, and reduce the manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the stator core structure of the yoke-separated motor of the present invention, wherein 101 is the yoke core, 102 is the stator teeth, and 103 is the stator slots.

[0031] Figure 2 and Figure 3 They are schematic diagrams of two types of tooth lamination structures of the tooth core of the present invention.

[0032] Figure 4 It is a schematic structural diagram of the yoke core laminations of the present invention.

[0033] Figure 5 Schematic diagram of the structure of the stator tooth core.

[0034] Figure 6 It is a schematic diagram of the structure of the stator yoke core.

[0035] Figure 7 It is a schematic diagram of the lamination arrangement of the tooth core of the present invention.

[0036] Figure 8 Schematic diagram of the dovetail mortise and tenon structure connection method.

[0037] Fig. 9 It is a schematic diagram of the design process of the motor stator core structure of the present invention.

[0038] Fig.10 Schematic diagram of the corresponding positions of stator tooth laminations and yoke laminations during stamping or cutting operations, where 103 is the stator slot and 104 is the stator tooth lamination.

[0039] Fig.11 The figure is a schematic diagram of the structure of a motor using a tooth-yoke separated stator according to an embodiment of the present invention.

[0040] Fig.12 3 is a stator stress distribution cloud diagram when the proportion η of the tooth lamination b is 0% in an embodiment of the present invention. In the figure, vonMises represents the equivalent stress calculated based on the von Mises yield criterion.

[0041] Fig.13 It is a stator stress distribution cloud diagram when the proportion η of the tooth lamination b is 20% in the embodiment of the present invention.

[0042] Fig.14 This is a surface diagram showing how the average torque of the motor varies with the slot width and height according to an embodiment of the present invention.

[0043] Fig.15 This is a surface diagram showing how the motor torque fluctuation value varies with the slot width and height according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to describe the present invention more specifically, the technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] like Figure 1 As shown, this embodiment takes an 18-slot concentrated flat wire winding motor stator core as an example, which adopts a tooth-yoke separation structure, mainly including a yoke core 101 and a tooth core; the stator core is an external stator form, and each stator tooth 102 and stator slot 103 is alternately arranged along the circumferential direction of the yoke, the stator tooth type is a right-angle root parallel tooth, the stator slot is a flat-bottomed slot, the slot type is approximately a pentagon, the bottom end of the slot is a wider side, and the end close to the slot mouth is a narrower side.

[0046] like Figure 6 As shown, the yoke core is a polygonal structure as a whole. Figure 4 The yoke laminations (silicon steel sheets) shown are stacked and a plurality of dovetail grooves are arranged on the inner wall, the shape of which matches the tooth root and the number of which corresponds to the number of stator teeth.

[0047] The tooth core is formed by laminating two different core laminations, including tooth lamination a and tooth lamination b; Figure 2As shown, the tooth lamination a is a plurality of independent stator tooth structures, and there is no connection between adjacent teeth, including the tooth root, tooth body, and tooth top. The tooth root is provided with a dovetail groove, and the shape is adapted to the dovetail groove shape of the yoke. The tooth shape of the tooth lamination b is the same as that of the tooth lamination a, and it is only connected to the adjacent teeth at the tooth shoe, so that the stator teeth are connected to each other as a whole, forming a sun tooth shape, as shown in FIG. Figure 3 The tooth laminations a and b are arranged in a certain pattern in the axial direction, specifically, the lamination module A formed by laminations of x tooth laminations a and the lamination module B formed by laminations of y tooth laminations b are alternately stacked in the axial direction, as shown in FIG. Figure 7 As shown, there are n laminated modules A and n+1 laminated modules B in the axial direction; the values ​​of x and y are determined by finite element, and the minimum value η=(n+1) / (2n+1) of the proportion of the tooth lamination b in the entire tooth core lamination is determined by finite element simulation verification of the stator mechanical strength, and the optimal combination of x and y values ​​is determined by finite element simulation of the electromagnetic scheme to make the motor leakage magnetic field and magnetic field harmonics as small as possible.

[0048] When the stator teeth are laminated, the tooth laminations a and b are arranged according to the optimal solution determined by finite element simulation, and the tooth roots, tooth bodies, and tooth tops of the tooth laminations a and b are completely overlapped, and then laminated and bonded to form a complete tooth core. Figure 5 As shown, adjacent teeth are connected through the tooth shoes of the tooth lamination b, and the thickness of the tooth lamination a or b is the same as the thickness of the yoke lamination, and the sum of the number of tooth laminations a and b is the same as the number of yoke laminations.

[0049] After the tooth core is processed, the winding is carried out. After completion, the tooth root and the dovetail groove on the yoke core are spliced ​​to form a complete stator core structure. Figure 8 The dovetail mortise and tenon structure shown is tightly matched to achieve a fixed connection between the two without the need for additional fasteners.

[0050] like Fig. 9 As shown, the design method of the motor stator core structure in this embodiment mainly includes the following steps:

[0051] (1) Determine the design indicators and parameter limits of the motor; determine the main dimensions and electromagnetic loads of the motor based on the design indicators; select appropriate pole-slot combinations and determine the preliminary design of the motor.

[0052] (2) By simulating the mechanical strength of the stator core structure, the approximate range of the minimum value η of the proportion of the tooth lamination b in the overall lamination is determined, so that the strength of the tooth shoe connection meets the design requirements.

[0053] (3) Through electromagnetic simulation, within the parameter limit range confirmed by the above mechanical strength simulation, compare the average torque and torque fluctuation performance of the motor under different parameter n, x, y matching schemes of the two types of lamination combinations, and select the best matching scheme; in this process, the magnetic permeability and stacking coefficient of the material selected at the slot connection can be modified to simulate the structure of the two types of lamination combinations at the slot in a two-dimensional simulation; after the preliminary design scheme is determined on this basis, a three-dimensional simulation verification is performed to reduce the time consumed by the preliminary scheme design.

[0054] (4) Based on the above preliminary design scheme, a multi-objective optimization method is used to obtain the curves of the influence of different slot widths, tooth shoulder heights, tooth widths, slot depths, stator inner diameters, and connection shapes on the torque performance. The parameters that have a greater impact on the motor torque performance are selected as optimization variables to further optimize the motor scheme.

[0055] (5) Perform mechanical strength check on the confirmed electromagnetic scheme to ensure that the mechanical strength of the stator meets the design requirements; and implement the design of the stator core of the yoke-separated motor.

[0056] The tooth-yoke separated stator core structure of this embodiment can be manufactured by wire cutting or stamping. The specific manufacturing method includes the following steps:

[0057] (1) During the stamping or cutting operation, rotate the stator teeth by a certain angle so that the tooth root is aligned with the yoke slot bottom, e.g. Fig.10 As shown, by utilizing the larger space of the stator slots 103 , the stator teeth laminations 104 and the yoke laminations can be cut out from the same silicon steel sheet.

[0058] (2) The yoke and tooth laminations are stacked and welded according to the scheme described in the above example, and the winding process is performed on the tooth module.

[0059] (3) The stator teeth and yoke are spliced ​​together through dovetail grooves to form a complete stator core structure.

[0060] The reason for not cutting directly at the original stator tooth root and yoke tooth position is that both wire cutting and stamping have a certain dimensional loss. Cutting out both sides of the slot at the same position will cause gaps at the joints, affecting the fit between the tooth and the yoke, resulting in reduced mechanical strength.

[0061] If the wire cutting processing scheme is adopted, a circular hole with a radius of the inner diameter of the stator can be cut on part of the silicon steel sheets first, and the position of the slot can be cut out after the circular hole is cut out on the other part of the silicon steel sheets. Then, the two types of semi-finished products are arranged according to the stacking method of the two types of tooth laminations in the above scheme. After alignment and fixation, the outer ring of the stator teeth and the yoke laminations are cut uniformly to reduce the number of wire cutting times.

[0062] The manufacturing process method of the above-mentioned core simplifies the winding process, making it easier to use high slot fill rate and large-size flat wire windings; the yoke is connected to the tooth part through the tight fit of the dovetail slot, without the need for additional fasteners; and the inner ring waste generated by cutting the yoke is reused by utilizing the space of the stator slot, thereby saving silicon steel materials to the greatest extent.

[0063] In summary, the tooth-yoke separated stator core structure of the present invention can solve the contradiction between the mechanical strength and electromagnetic efficiency of the tooth-yoke separated stator, improve the efficiency of the tooth-yoke separated stator motor, and at the same time greatly improve the material utilization rate in the processing process and reduce the manufacturing cost.

[0064] like Fig.11 The figure shows the overall structure of the motor with a tooth-yoke separated stator in this embodiment, including a yoke core, a tooth core, a rotor and a winding structure arranged in the stator slots. The electromagnetic design scheme in this embodiment adopts an 18-slot 20-pole structure, the stator outer diameter is 148mm, and the axial length is 50mm.

[0065] The parameters in this embodiment that are different from those in conventional motor design mainly include: the minimum value η of the proportion of the stator tooth lamination b in the overall stator tooth lamination, the combined arrangement parameters n, x, y of the two types of laminations, and the slot width and slot height of the slot position. These parameters will have a certain impact on the electromagnetic performance and mechanical strength of the motor.

[0066] After the motor design method in this embodiment confirms the main dimensions of the motor through the design indicators, it is necessary to first simulate the mechanical strength to determine the approximate range of the minimum value η of the proportion of the motor stator tooth lamination b in the stator tooth lamination as a whole. Fig.12 and Fig.13 As shown, compared with conventional yoke-separated motors, the motor designed using this embodiment has significantly reduced stress at the yoke connection, and the maximum stress position of the tooth part is transferred from the yoke connection to the tooth top connection. When the η value is small, the tooth top connection may deform due to excessive force; and when the η value is too large, although the mechanical strength is improved, it will also cause a large leakage magnetic field between the teeth, affecting the torque output performance of the motor. When the η value is constant, the axial position distribution of the tooth lamination b has a relatively small effect on the maximum stress. In this embodiment, the η value range selected is ≥15%.

[0067] After determining the parameter limit range of the motor's mechanical strength, it is also necessary to compare the average torque and torque fluctuation performance of the motor under different η values ​​and two types of lamination combination arrangement parameters n, x, y, and select the best matching scheme. The average torque of the motor is negatively correlated with the η value, so taking a lower η value can effectively improve the torque output of the motor, while the relationship between torque fluctuation and η value is more complicated.

[0068] Under normal circumstances, the torque fluctuation value of the motor increases first and then decreases with the increase of the slot width and slot height, and the proportion of Class B laminations will affect the magnetic permeability of the slot position of the motor, resulting in the slot width corresponding to the maximum value of the torque fluctuation increasing with the increase of the η value, and the slot height corresponding to the maximum value of the torque fluctuation decreasing with the increase of the η value; and for general motors, the sensitivity of the torque performance to the slot width is higher than that to the slot height. However, in this embodiment, as the η value increases, the sensitivity of the motor torque performance to the change of the slot width gradually decreases, while the sensitivity to the change of the slot height increases significantly, resulting in different laws of the change of the motor torque fluctuation with the η value when different slot widths and heights are selected.

[0069] In this embodiment, in order to obtain higher torque output and reduce inter-tooth magnetic leakage, the η value is selected to be 20%, and on this basis, the slot width and height are optimized. The specific relationship curve is as follows: Fig.14 and Fig.15 As shown, the final slot structure used has a width of 6 mm and a height of 0.5 mm.

[0070] On the basis of the above scheme, we determined the matching scheme of two types of lamination combination arrangement parameters n, x, y by building a three-dimensional model. The influence of these parameters on the average torque is relatively small, the torque fluctuation is roughly negatively correlated with the n value, and the maximum stress at the tooth top connection is roughly positively correlated with the n value. Therefore, it is necessary to select the values ​​of n, x, and y according to the requirements of the motor design scheme; in this embodiment, the thickness of the silicon steel sheet lamination is selected to be 0.2 mm, and the final n value is 4, the x value is 50, and the y value is 10.

[0071] It can be seen that the tooth-yoke separated stator structure of the present invention combines the advantages of the tooth-yoke separated motor and the block gear motor, optimizes the torque performance of the motor while ensuring the mechanical strength, and improves the efficiency of the tooth-yoke separated stator motor.

[0072] The above description of the embodiments is to facilitate the understanding and application of the present invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to the above embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments. Improvements and modifications made by those skilled in the art to the present invention based on the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. A method for manufacturing a stator core structure of a tooth-yoke separated motor, comprising an annular yoke core and a tooth core, characterized in that: The inner wall of the yoke core is provided with a plurality of dovetail tenons along the circumferential direction, and the stator tooth root of the tooth core is provided with a dovetail groove adapted to the shape of the dovetail tenon; the tooth core is formed by laminating two types of tooth laminations a and b, the tooth lamination a is a mutually independent block tooth structure, and the adjacent teeth are not connected; the tooth lamination b is an integral tooth structure, the adjacent teeth are connected at the tooth shoe, and all teeth are connected to each other along the circumferential direction to form a sun tooth shape; The lamination arrangement of the tooth core adopts two lamination modules A and B arranged alternately along the axial direction, the lamination module A is formed by laminating x tooth laminations a, and the lamination module B is formed by laminating y tooth laminations b, the number of lamination modules A is n, and the number of lamination modules B is n+1; the dovetail tenon of the yoke core and the dovetail groove at the root of the stator tooth are connected to each other by a mortise and tenon structure; The yoke core is formed by laminating yoke laminations, the thickness of the tooth lamination a or b is the same as the thickness of the yoke lamination, and the sum of the number of tooth laminations a and b is the same as the number of yoke laminations; During the cutting operation, the stator teeth are rotated by a certain angle by a rotational dislocation processing method, so that the tooth root corresponds to the position of the stator yoke slot bottom, and the tooth laminations and yoke laminations are cut from the same silicon steel sheet; For the thickness ratio of stacking modules A and B, i.e. the values ​​of x and y, the design optimization method is as follows: (1) Determine the parameter range of the minimum lamination ratio η of the tooth lamination b in the tooth core through mechanical strength simulation, so that the strength of the tooth shoe connection meets the design requirements; (2) Through electromagnetic simulation, within the parameter range determined by the above mechanical strength simulation, the average torque and torque fluctuation performance of the motor under different parameter n, x, y matching schemes of the two types of lamination combinations are compared, and the best matching scheme is selected as the preliminary design scheme; in this process, by modifying the magnetic permeability and stacking coefficient of the material selected at the slot connection, the structure of the two types of lamination combinations of the slot is simulated in a two-dimensional simulation, and the preliminary design scheme is determined on this basis and then a three-dimensional simulation verification is performed to reduce the time consumed by the scheme design; (3) Based on the preliminary design scheme, the relationship curve of the influence of different slot widths, tooth shoulder heights, tooth widths, slot depths, stator inner diameters, and connection shapes on torque performance is obtained through multi-objective optimization, and the parameters that have a greater impact on the motor torque performance are selected as optimization variables, so as to further optimize the preliminary design scheme; (4) Perform mechanical strength check on the optimized design to ensure that the mechanical strength of the stator meets the design requirements, thereby obtaining the final design of the stator core structure of the yoke-separated motor.

2. The method for manufacturing the stator core structure of the gear-yoke separation motor according to claim 1, characterized in that: The stator slots formed by splicing the yoke core and the tooth core are flat-bottomed slots, and have both semi-closed slot and closed slot structures.

3. The method for manufacturing the stator core structure of the gear-yoke separation motor according to claim 1, characterized in that: The processing method of the rotational dislocation is specifically as follows: firstly, a circular hole with a radius equal to the inner diameter of the stator is cut on a part of the silicon steel sheet, and after the circular hole is cut out on the other part of the silicon steel sheet, the position of the notch is cut out, and then the two types of semi-finished products are arranged according to the stacking method of the two types of tooth laminations, and after alignment and fixing, the outer ring of the stator teeth and the yoke laminations are uniformly cut, and the contact surface of the tooth and the yoke is further trimmed; When the tooth core is laminated, the two tooth laminations are arranged according to the optimal configuration parameters determined by finite element simulation, and the tooth roots, tooth bodies and tooth tops of the two tooth laminations are completely overlapped before being laminated, bonded and welded. The adjacent teeth are connected through the tooth boots of the tooth lamination b. During assembly, the wound coil winding is first installed on the stator tooth, and then the position of the stator tooth root and the stator yoke connection is aligned, so that the yoke core and the tooth core are spliced ​​and formed through the mortise and tenon structure.

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