Stator structure and motor

Abstract

The invention provides a stator structure and a motor, and relates to the technical field of motors. The stator structure comprises a stator body and a first winding; the stator body is cylindrical, and a plurality of stator grooves are formed in the inner side wall of the stator body; the stator slot comprises a first slot body and a second slot body which are communicated with each other, the first winding penetrates through the first slot body, and the second slot body is located on one side, facing the center of the stator body, of the first slot body; the depth of each stator groove is H, the thickness of the stator body in the radial direction of the stator body is W, and H: W is larger than or equal to 1: 2.2 and smaller than or equal to 1: 1.1. According to the stator structure, the deep groove design is adopted, under the condition that the size of the stator is kept unchanged, the first groove body for the first winding to penetrate through is farther from the center of the stator body, and a larger space is formed in the circumferential direction of the stator body, so that the first groove body can be wider, the groove fullness rate of the first winding in the first groove body is increased, and the winding efficiency is improved. And the resistance of the first winding is lower, and the equivalent heat conductivity coefficient is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a stator structure and a motor. Background Art

[0002] High-speed motors have the advantages of small size and high power density. In order to reduce the spatial harmonic content of the air gap magnetic field, they usually adopt a multi-slot design, so the teeth and slots are relatively narrow. As the drive load increases, high-speed motors usually use formed windings. At this time, the advantage of the high-speed motor's own small size will bring the disadvantage of low slot fill rate. The reason is that the stator of the high-speed motor is small, which means that the slot of the stator to accommodate the formed winding is very narrow, and the insulation thickness of the high-voltage formed winding is determined by the voltage level, and it will not become thinner as the slot becomes narrower, which results in a low slot fill rate of the winding. Not only does it increase the resistance of the winding and increase the copper loss of the winding, but the high proportion of insulation material also causes the equivalent thermal conductivity of the entire winding to decrease, which in turn increases the temperature rise of the winding and reduces the insulation life. Summary of the invention

[0003] In order to solve the problems existing in the prior art, one of the objectives of the present invention is to provide a stator structure.

[0004] The present invention provides the following technical solutions: A stator structure comprises a stator body and a first winding; The stator body is provided in a cylindrical shape, and a plurality of stator slots are provided on the inner side wall of the stator body. The stator slots are extended along the radial direction of the stator body, and the plurality of stator slots are arranged along the circumferential direction of the stator body; The stator slot comprises a first slot body and a second slot body which are connected to each other, the first winding is arranged in the first slot body, and the second slot body is located on a side of the first slot body facing the center of the stator body; The depth of the stator slot is H, the depth of the first slot body is H1, the thickness of the stator body along its radial direction is W, 1:2.2≤H:W≤1:1.1, and the determination of the first slot body depth needs to consider the eddy current loss of the first winding, and the eddy current loss coefficient is calculated by the following formula: ; ; k ACR is the eddy current loss coefficient of the first winding, h is the height of a single conductor in the first winding, is the skin depth, is the phase angle of the first winding between two adjacent layers.

[0005] As a further optional solution for the stator structure, the stator body includes a yoke and a plurality of teeth, the yoke is arranged in a cylindrical shape, the teeth are extended along the radial direction of the yoke, one end of the teeth is connected to the inner edge of the yoke, the plurality of teeth are arranged along the circumference of the yoke, the stator slot is formed between two adjacent teeth, a slot wedge is arranged in the stator slot, and the slot wedge is located on the side of the first slot body facing the center of the stator body; The depth of the stator slot is calculated by the following formula: ; ; ; ; t1 is the tooth pitch, B δ is the air gap flux density, K Fe is the lamination stacking coefficient, B t is the tooth magnetic flux density, D i1 is the inner diameter of the stator body, h ex is the distance that the stator slot extends toward the yoke, h s is the original depth of the stator slot, Z is the number of the stator slots, b s is the width of the first slot body, H2 is the initial depth of the second slot body, ΔH is the thickness of the slot wedge along the radial direction of the stator body, Δh is the total thickness of the insulating layer in the first winding along the radial direction of the stator body, Δb is the total thickness of the insulating layer in the first winding along the circumferential direction of the stator body, and C is a constant.

[0006] As a further optional solution for the stator structure, the second slot body has a first slot wall and a second slot wall that are arranged opposite to each other, and the distance between the first slot wall and the second slot wall gradually decreases in a direction away from the first slot body.

[0007] As a further optional solution for the stator structure, a protrusion is provided at one end of the first slot wall close to the first slot body.

[0008] As a further optional solution for the stator structure, the second slot body has a first slot wall and a second slot wall arranged opposite to each other, the first slot wall and the second slot wall are parallel to each other, and the width of the second slot body is smaller than the width of the first slot body.

[0009] As a further optional solution for the stator structure, the first winding includes two first coils, the first coils are embedded in the first slot body along the radial direction of the stator body, and the two first coils are arranged side by side along the width direction of the first slot body.

[0010] As a further optional solution for the stator structure, the first winding includes a second coil, the second coil is embedded in the first slot along the axial direction of the stator body, and the end of the second coil along the axial direction of the stator body is welded to the adjacent second coil.

[0011] As a further optional solution for the stator structure, the stator structure further includes a second winding, the second winding is arranged through the second slot body, and the second winding is electrically connected to the first winding.

[0012] Another object of the present invention is to provide a motor.

[0013] The present invention provides the following technical solutions: A motor comprises the above-mentioned stator structure.

[0014] As a further optional solution for the motor, the motor further includes a bearing, at least part of which is located inside the first winding.

[0015] The embodiments of the present invention have the following beneficial effects: The above-mentioned stator structure adopts a deep slot design, and the ratio of the depth of the stator slot to the thickness of the stator body along its radial direction is between 1:2.2 and 1:1.1. When the volume of the stator remains unchanged, the first slot body for the first winding to pass through is farther from the center of the stator body, and has a larger space along the circumference of the stator body, so the first slot body can be made wider. When the voltage is constant, that is, the thickness of the insulation layer is constant, after the slot width of the first slot body increases, the proportion of the insulation layer in the first slot body decreases and the proportion of copper increases, thereby improving the slot fill rate of the first winding in the first slot body, making the resistance of the first winding lower and the equivalent thermal conductivity higher. At the same time, when the height of a single conductor in the first winding, the skin depth and the phase angle of two adjacent layers of the first winding are known, according to the desired eddy current loss coefficient, the height of the first winding, that is, the depth of the first slot body, can be calculated by the above formula, so as to design a stator slot of appropriate size.

[0016] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 The figure shows an overall structural schematic diagram of a stator structure provided by an embodiment of the present invention; Figure 2 A partial structural schematic diagram of a stator structure provided by an embodiment of the present invention is shown; Figure 3 A schematic diagram of a local structure of a stator structure after the depth of the stator slot is increased is shown; Figure 4 The simulation result diagram of eddy current loss of 32-layer conductor is shown; Figure 5 A schematic diagram of a local structure of a stator structure after increasing the depth and width of the stator slots is shown; Figure 6 The simulation result diagram of eddy current loss of 16-layer conductor is shown; Figure 7 A graph showing the relationship between the eddy current loss factor and the winding height ratio; Figure 8 A partial structural schematic diagram of a stator structure provided by an embodiment of the present invention is shown; Fig. 9 A partial structural schematic diagram of a stator structure provided by another embodiment of the present invention is shown; Fig.10 A partial structural schematic diagram of a stator structure provided by another embodiment of the present invention is shown; Fig.11 A partial structural schematic diagram of a stator structure provided by yet another embodiment of the present invention is shown; Fig.12 A schematic diagram of the overall structure of a motor provided by an embodiment of the present invention is shown.

[0019] Description of main component symbols: 10-stator structure; 20-housing; 30-rotor; 40-bearing; 100- stator body; 110- stator slot; 111- first slot body; 112- second slot body; 112a- first slot wall; 112b- second slot wall; 112c- raised portion; 120- yoke; 130- tooth portion; 200- first winding; 300- slot wedge; 400- second winding. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0021] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0022] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between 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.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of the template are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0025] Example The present embodiment provides a stator structure 10, which is applied to a motor, and is particularly applicable to a high-speed, high-voltage, and high-power motor. A high-speed motor generally refers to a motor with a rotation speed exceeding 10,000 rpm. In addition, the power of the motor exceeds 500 kW, and a molded winding is generally used. The molded winding is made of a flat wire, and its cross section is rectangular.

[0026] Please also read Figure 1 and Figure 2 The stator structure 10 includes a stator body 100 and a first winding 200 .

[0027] Specifically, the stator body 100 is provided in a cylindrical shape, and a plurality of stator slots 110 are provided on the inner wall of the stator body 100. The stator slots 110 are extended along the radial direction of the stator body 100, and the plurality of stator slots 110 are arranged along the circumferential direction of the stator body 100.

[0028] In addition, the stator slot 110 includes a first slot body 111 and a second slot body 112 which are connected to each other. The first winding 200 is disposed in the first slot body 111 , and the second slot body 112 is located on one side of the first slot body 111 facing the center of the stator body 100 .

[0029] The depth of the stator slot 110 is H, the depth of the first slot body 111 is H1, and the thickness of the stator body 100 along its radial direction is W. It satisfies 1:2.2≤H:W≤1:1.1, and the determination of the depth of the first slot body 111 needs to consider the eddy current loss of the first winding 200. The eddy current loss coefficient is calculated by the following formula: ; ; k ACR is the eddy current loss coefficient of the first winding 200, h is the height of a single conductor in the first winding 200, is the skin depth, is the phase angle of the first winding 200 of two adjacent layers.

[0030] It is understandable that in the process of motor design, for different motor stator structures 10, the height h of the conductor, the skin depth and the phase angle of the first winding 200 of two adjacent layers They are not necessarily the same, but can be adjusted as needed. However, when calculating the depth H1 of the first slot body 111, h, , are considered as constants, and the value of H1 depends on the desired eddy current loss coefficient k ACR .

[0031] In particular, when the first slot 111 is provided with only one layer of the first winding 200, the phase angles of the first windings 200 of two adjacent layers are Treated as 0.

[0032] The stator structure 10 adopts a deep slot design, and the ratio of the depth of the stator slot 110 to the thickness of the stator body 100 along its radial direction is between 1:2.2 and 1:1.1. When the volume of the stator remains unchanged, the first slot body 111 for the first winding 200 to pass through is farther from the center of the stator body 100, and has a larger space along the circumference of the stator body 100, so that the first slot body 111 can be made wider, thereby increasing the slot fill rate of the first winding 200 in the first slot body 111, making the resistance of the first winding 200 lower and the equivalent thermal conductivity higher. At the same time, when the height, skin depth and phase angle of the adjacent two layers of the first winding 200 of the single conductor in the first winding 200 are known, according to the desired eddy current loss coefficient, the height of the first winding 200, that is, the depth of the first slot body 111, can be calculated by the above formula, so as to design the stator slot 110 of appropriate size.

[0033] It should be noted that the high-voltage formed winding is made of flat wire, and its cross section is rectangular, so the slots of the high-voltage motor stator that accommodate the formed winding must be parallel slot structures, that is, the two sides of the stator slot 110 are parallel. Based on this premise, Figure 3 As shown, if the depth of the stator slot 110 is simply increased, although it can accommodate the necessary copper wire area, it still cannot solve the defects such as low slot fill rate and reduced equivalent thermal conductivity.

[0034] In addition, according to Ampere's loop theorem, the leakage magnetic field in the stator slot 110 is proportional to the distance from the formed winding to the slot bottom. Figure 4 , it can be seen from the simulation results of the eddy current loss of the formed winding composed of 32 layers of conductors that the closer the formed winding is to the slot position, the more obvious the skin effect of the internal conductor is, and the greater the eddy current loss is. In other words, the narrower and taller the formed winding is, the greater the eddy current loss generated by the leakage magnetic field in the stator slot 110 on the formed winding, and the eddy current loss is approximately proportional to the square of the frequency, which is a fatal defect for high-speed motors (frequency is usually above 300Hz, much higher than the traditional 50Hz low-frequency motor).

[0035] Secondly, this slot-type structure will cause the bell mouth of the end of the formed winding along the axial direction of the stator body 100 to become smaller, which cannot accommodate the bearing 40, causing the motor to become longer in the axial direction, which will lead to a low critical speed.

[0036] Furthermore, this narrow and high shaped winding is not conducive to production and manufacturing, and the bending nose at the end is difficult to bend, which can easily cause insulation damage. Finally, when the narrow and high shaped winding is insulated, the height of its cross section is much greater than its width, which will lead to unstable tension of the machine insulation tape and loose winding on the side of the winding, which can easily cause insulation gaps.

[0037] like Figure 5As shown, if the width of the stator slot 110 is forcibly widened while increasing the depth of the stator slot 110, the teeth on the inner circle of the stator body 100 will be very narrow, causing serious saturation at the narrow part of the tooth portion 130. For the asynchronous motor, this means an increase in the excitation current and a decrease in the power factor. For the permanent magnet motor, this means more permanent magnets for excitation.

[0038] In contrast, the above-mentioned stator structure 10 adopts a deep slot design while dividing the stator slot 110 into a first slot body 111 and a second slot body 112, and uses the first slot body 111 that is farther from the center of the stator body 100 for the first winding 200 to pass through. At this time, the first slot body 111 can be made wider without changing the tooth width. When the voltage is constant, that is, the thickness of the insulating layer is constant, after the slot width of the first slot body 111 is increased, the proportion of the insulating layer in the first slot body 111 becomes smaller and the proportion of copper becomes larger. In addition to increasing the slot fill rate of the first winding 200 in the first slot body 111, making the resistance of the first winding 200 lower and the equivalent thermal conductivity higher, the width of the first winding 200 is increased and the height is reduced.

[0039] On this basis, the shaped winding is changed from a narrow and high type to a wide and short type, and the distance between the side of the shaped winding close to the center of the stator body 100 and the bottom of the stator slot 110 is reduced, so the eddy current loss caused by the slot leakage magnetic field is reduced. Figure 6 ,From the eddy current loss simulation results of the formed winding composed of 16 layers of conductors, it can be seen that the eddy current loss of the wide and short formed winding is significantly smaller.

[0040] In addition, the vacant second slot 112 enlarges the bell mouth of the end of the first winding 200 along the axial direction of the stator body 100, which can accommodate the bearing 40, reduce the axial length of the motor, and increase the critical speed of the rotor 30, so that the high-speed motor can safely operate below the first-order critical speed. Finally, the bending nose of the end of the first winding 200 along the axial direction of the stator body 100 is easier to bend, and the tension of the machine package insulation tape is more uniform, the wrapping is tighter, and the insulation gap is reduced.

[0041] Specifically, the AC resistance of the first winding 200 is R AC , the DC resistance of the first winding 200 is R DC Given a basic winding height, denoted as H W , and set the winding height ratio to k, then: ; .

[0042] Generally, the short-distance coefficient of the motor is 5 / 6. For the entire motor winding, the above formula can be simplified to: .

[0043] When the first winding 200 is a full-pitch winding or a single-layer winding, for the entire motor winding, the above formula can be simplified to: .

[0044] See also Figure 7 Taking the full-pitch winding as an example, the relationship curve between the eddy current loss coefficient and the winding height ratio is plotted according to the above formula, and it can be seen that: When the winding height ratio is 1, the eddy current loss coefficient is 1.8. When the winding height ratio is doubled, the eddy current loss coefficient is 4.21, which increases by 1.34 times. Since the winding copper loss accounts for a large proportion of the total motor loss (about 15%-30%), the eddy current loss increased by the increase in the winding height ratio will significantly reduce the motor efficiency.

[0045] It should be noted that, in the motor design process, no matter how the depth H1 of the first slot 111 (ie, the height of the first winding 200) changes, the DC resistance of the first winding 200 is R DC In the first winding 200, the conductors are connected in parallel, so the sum of the cross-sectional areas of the conductors needs to remain unchanged.

[0046] On this basis, as the depth of the first slot body 111 decreases, the size of each conductor in the first winding 200 along the radial direction of the stator body 100 becomes smaller, so the size of each conductor along the circumferential direction of the stator body 100 increases accordingly, which means that the width of the first slot body 111 increases.

[0047] Therefore, after calculating the depth of the first slot body 111 according to the desired eddy current loss coefficient, the width of the first slot body 111 can be further calculated, and then the position of the first slot body 111 on the stator body 100, that is, the depth of the stator slot 110, can be determined in combination with the size parameters of the stator body 100.

[0048] In some embodiments, the stator body 100 includes a yoke 120 and a plurality of teeth 130. The yoke 120 is arranged in a cylindrical shape. The teeth 130 are extended along the radial direction of the yoke 120, and one end of the teeth 130 is connected to the inner edge of the yoke 120. The plurality of teeth 130 are arranged along the circumference of the yoke 120, and a stator slot 110 is formed between two adjacent teeth 130. A slot wedge 300 is arranged in the stator slot 110, and the slot wedge 300 is located on the side of the first slot body 111 facing the center of the stator body 100.

[0049] In addition, the depth of the stator slot 110 is calculated by the following formula: ; ; ; ; t1 is the tooth pitch, B δ is the air gap flux density, K Fe is the lamination stacking coefficient, B t is the magnetic flux density of tooth 130, D i1 is the inner diameter of the stator body 100, h ex h is the distance that the stator slot 110 extends toward the yoke 120, s is the original depth of the stator slot 110, Z is the number of the stator slots 110, b s is the width of the first slot body 111, H2 is the initial depth of the second slot body 112, ΔH is the thickness of the slot wedge 300 along the radial direction of the stator body 100, Δh is the total thickness of the insulating layer in the first winding 200 along the radial direction of the stator body 100, Δb is the total thickness of the insulating layer in the first winding 200 along the circumferential direction of the stator body 100, and C is a constant.

[0050] It should be noted that the original depth h of the stator slot 110 is s It refers to the depth of the stator slot 110 obtained according to the conventional open slot design. At this time, the side of the slot wedge 300 away from the bottom of the stator slot 110 is substantially flush with the inner edge of the stator body 100, and the stator slot 110 substantially only includes the first slot body 111, and the initial depth H2 of the second slot body 112 is zero.

[0051] In the motor design process, on the one hand, according to the tooth pitch t1, air gap magnetic flux density B δ , Punching lamination coefficient K Fe 、Gear 130 magnetic density B t The tooth width required for electromagnetic design can be calculated; on the other hand, in h ex = 0 (conventional stator slot 110 design), according to the inner diameter D of the stator body 100 i1 , the original depth h of the stator slot 110 s , the number Z of the stator slots 110 , the width b of the first slot body 111 s The actual tooth width can be calculated.

[0052] Since the formed winding adopts a wide and short design, the actual tooth width is usually smaller than the tooth width required to meet the electromagnetic design. At this time, the stator slot 110 is extended to the yoke 120 by a certain distance h ex , the tooth width between two adjacent first slot bodies 111 can be increased until the actual tooth width is the same as the tooth width required to meet the electromagnetic design.

[0053] Finally, the depth of the stator slot 110 can be calculated according to the original depth of the stator slot 110 and the distance the stator slot 110 extends toward the yoke 120 .

[0054] It can be understood that the stator slot 110 extends toward the yoke 120 by a certain distance h ex After that, the first slot body 111 and the slot wedge 300 are moved outward by the same distance h along the radial direction of the stator body 100. ex At this time, the slot wedge 300 is no longer flush with the inner edge of the stator body 100, and the space between the slot wedge 300 and the inner edge of the stator body 100 serves as the second slot body 112, and the depth of the second slot body 112 is equal to h ex .

[0055] In addition, the dimension of each conductor in the first winding 200 along the radial direction of the stator body 100 can be obtained by subtracting the total thickness of the insulating layer in the first winding 200 along the radial direction of the stator body 100 from the depth of the first slot 111. The dimension of each conductor in the first winding 200 along the circumferential direction of the stator body 100 can be obtained by subtracting the total thickness of the insulating layer in the first winding 200 along the circumferential direction of the stator body 100 from the width of the first slot 111. As mentioned above, the sum of the cross-sectional areas of each conductor needs to remain unchanged, so the product of the dimension of each conductor along the radial direction of the stator body 100 and the dimension of each conductor along the circumferential direction of the stator body 100 is a constant. After confirming the depth of the first slot 111, the width b of the first slot 111 can be calculated. s , and then calculate the actual tooth width.

[0056] Similarly, in the process of motor design, for different motor stator structures 10, the tooth pitch t1, air gap flux density B δ , Punching lamination coefficient K Fe 、Gear 130 magnetic density B t , the inner diameter D of the stator body 100 i1 , the number Z of the stator slots 110, the preset increment ΔH of the stator slots 110, the total thickness Δh of the insulating layer in the first winding 200 along the radial direction of the stator body 100, and the total thickness Δb of the insulating layer in the first winding 200 along the circumferential direction of the stator body 100 are not necessarily the same, but can be adjusted as needed. However, when calculating the depth H of the stator slot 110, each parameter is considered a constant.

[0057] See also Figure 8 In some embodiments, the second groove body 112 has a first groove wall 112 a and a second groove wall 112 b that are arranged opposite to each other, and the distance between the first groove wall 112 a and the second groove wall 112 b gradually decreases in a direction away from the first groove body 111 .

[0058] At this time, the tooth portion 130 between two adjacent second slot bodies 112 still has a sufficient width to meet the requirements of electromagnetic design.

[0059] Exemplarily, the first slot wall 112a and the second slot wall 112b are respectively provided with protrusions on one side close to the first slot body 111. A limiting space for the slot wedge 300 to be inserted is formed between the two protrusions and the first winding 200 inserted into the first slot body 111. Along the radial direction of the stator body 100, one end of the slot wedge 300 abuts against the first winding 200, and the other end abuts against the two protrusions, thereby preventing the first winding 200 from being separated from the first slot body 111 along the radial direction of the stator body 100.

[0060] See also Fig. 9 Alternatively, the first slot wall 112a and the second slot wall 112b may be respectively provided with recesses on one side close to the first slot body 111, and the two sides of the slot wedge 300 are respectively inserted into the two recesses.

[0061] Please refer again Figure 2 Furthermore, a protrusion 112c is provided at one end of the first slot wall 112a close to the first slot body 111, which can fully utilize the slot space at the slot wedge 300 and reduce the magnetic density of the tooth portion 130.

[0062] See also Fig.10 In other embodiments, the second groove body 112 has a first groove wall 112a and a second groove wall 112b that are arranged opposite to each other, the first groove wall 112a and the second groove wall 112b are parallel to each other, and the width of the second groove body 112 is smaller than the width of the first groove body 111.

[0063] Although the second slot body 112 is closer to the center of the stator body 100 , since the width of the second slot body 112 is smaller, the tooth portion 130 between two adjacent second slot bodies 112 still has a sufficient width to meet the requirements of electromagnetic design.

[0064] In some embodiments, the first winding 200 includes two first coils. The first coils are embedded in the first slot 111 along the radial direction of the stator body 100 , and the two first coils are arranged side by side along the width direction of the first slot 111 .

[0065] Since the slot width of the stator slot 110 is smaller than the width of the first slot body 111 and the width of the first winding 200 is close to the width of the effective first slot body 111 , the first winding 200 is divided into two independent parallel coils in the slot width direction.

[0066] During assembly, the two first coils can be sequentially inserted into the stator slots 110 from the inner circular notch. The two first coils arranged side by side are processed together in pairs during drawing and re-forming to ensure that the end dimensions match. The first coils are individually wrapped with insulation and numbered in pairs, and are used in pairs during wire insertion. During wiring, the two first coils arranged side by side are connected in parallel and regarded as one.

[0067] By adopting the above-mentioned wire embedding method, there are fewer welding points and the coil consistency is high.

[0068] In other embodiments, the first winding 200 includes a second coil. The second coil is embedded in the first slot 111 along the axial direction of the stator body 100, and the end of the second coil along the axial direction of the stator body 100 is welded to the adjacent second coil.

[0069] Specifically, the first winding 200 is an open coil and is a single conductor along the slot width direction. During assembly, the second coil is inserted into the first slot body 111 along the axial direction of the stator body 100, and the opening at the end of the second coil is connected by welding or the like, similar to the hair pin structure of the flat wire winding of an electric vehicle.

[0070] By adopting the above-mentioned wire embedding method, the proportion of the insulation layer along the slot width direction is small and the slot fill rate is high.

[0071] See also Fig.11 In some embodiments, the stator structure 10 further includes a second winding 400 . The second winding 400 is disposed in the second slot body 112 . The second winding 400 is electrically connected to the first winding 200 , and the area of ​​the stator slot 110 can be fully utilized.

[0072] The second winding 400 and the first winding 200 may be connected in series or in parallel.

[0073] It should be noted that the electromagnetic wire material in the coil can be copper wire or aluminum wire. The electromagnetic wire structure can be flat wire, Litz wire or other types of conductors. The first winding 200 in the first slot 111 can be single-layer or double-layer.

[0074] In summary, the stator structure 10 adopts a deep slot design to replace the slot width space with the radial space, which reduces the magnetic density and eddy current loss of the tooth 130 and is more conducive to the manufacture and assembly of the coil and the stator.

[0075] See also Fig.12 This embodiment also provides a motor, including the above-mentioned stator structure 10.

[0076] In addition, the motor further includes a housing 20 and a rotor 30. The stator body 100 is fixedly disposed on the inner wall of the housing 20 and is disposed around the rotor 30. The rotor 30 passes through the stator body 100 and the housing 20 at the same time and is rotatably disposed on the housing 20.

[0077] Furthermore, the motor further includes a bearing 40 , and at least a portion of the bearing 40 is located inside the first winding 200 .

[0078] Accordingly, the rotor 30 is rotatably connected to the housing 20 via the bearing 40 .

[0079] At this time, the axial length of the motor is reduced, the critical speed of the rotor 30 is increased, and the high-speed motor can safely operate below the first-order critical speed.

[0080] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0081] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0082] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A stator structure, characterized in that: comprising a stator body and a first winding; The stator body is provided in a cylindrical shape, and a plurality of stator slots are provided on the inner side wall of the stator body. The stator slots are extended along the radial direction of the stator body, and the plurality of stator slots are arranged along the circumferential direction of the stator body; The stator slot comprises a first slot body and a second slot body which are connected to each other, the first winding is arranged in the first slot body, and the second slot body is located on a side of the first slot body facing the center of the stator body; The depth of the stator slot is H, the depth of the first slot body is H1, the thickness of the stator body along its radial direction is W, 1:2.2≤H:W≤1:1.1, and the determination of the first slot body depth needs to consider the eddy current loss of the first winding, and the eddy current loss coefficient is calculated by the following formula: ； ； k ACR is the eddy current loss coefficient of the first winding, h is the height of a single conductor in the first winding, is the skin depth, is the phase angle of the first winding between two adjacent layers.

2. The stator structure according to claim 1, characterized in that: The stator body comprises a yoke and a plurality of teeth, the yoke is arranged in a cylindrical shape, the teeth are extended along the radial direction of the yoke, one end of the teeth is connected to the inner edge of the yoke, the plurality of teeth are arranged along the circumference of the yoke, a stator slot is formed between two adjacent teeth, a slot wedge is arranged in the stator slot, and the slot wedge is located on the side of the first slot body facing the center of the stator body; The depth of the stator slot is calculated by the following formula: ； ； ； ； t1 is the tooth pitch, B δ is the air gap flux density, K Fe is the lamination stacking coefficient, B t is the tooth magnetic flux density, D i1 is the inner diameter of the stator body, h ex is the distance that the stator slot extends toward the yoke, h s is the original depth of the stator slot, Z is the number of the stator slots, b s is the width of the first slot body, H2 is the initial depth of the second slot body, ΔH is the thickness of the slot wedge along the radial direction of the stator body, Δh is the total thickness of the insulating layer in the first winding along the radial direction of the stator body, Δb is the total thickness of the insulating layer in the first winding along the circumferential direction of the stator body, and C is a constant.

3. The stator structure according to claim 1, characterized in that: The second slot body comprises a first slot wall and a second slot wall which are arranged opposite to each other, and a distance between the first slot wall and the second slot wall gradually decreases in a direction away from the first slot body.

4. The stator structure according to claim 3, characterized in that: A protrusion is provided at one end of the first slot wall close to the first slot body.

5. The stator structure according to claim 1, characterized in that: The second groove body has a first groove wall and a second groove wall which are arranged opposite to each other, the first groove wall and the second groove wall are parallel to each other, and the width of the second groove body is smaller than the width of the first groove body.

6. The stator structure according to any one of claims 1 to 5, characterized in that: The first winding includes two first coils, the first coils are embedded in the first slot body along the radial direction of the stator body, and the two first coils are arranged side by side along the width direction of the first slot body.

7. The stator structure according to any one of claims 1 to 5, characterized in that: The first winding includes a second coil, the second coil is embedded in the first slot along the axial direction of the stator body, and the end of the second coil along the axial direction of the stator body is welded to the adjacent second coil.

8. The stator structure according to any one of claims 1 to 5, characterized in that: The stator structure further includes a second winding, the second winding is arranged in the second slot body, and the second winding is electrically connected to the first winding.

9. A motor, characterized in that: The invention comprises the stator structure according to any one of claims 1 to 8.

10. The motor according to claim 9, characterized in that The motor further comprises a bearing, at least part of which is located inside the first winding.

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