A stator structure and a motor

Abstract

The present invention provides a stator structure and a motor, relating to the technical field of motors. The stator structure includes a stator body and a first winding; the stator body is arranged in a cylindrical shape, and a plurality of stator slots are provided on the inner side wall of the stator body; the stator slots include a first slot body and a second slot body that are in communication with each other, the first winding is disposed through the first slot body, and the second slot body is located on the side of the first slot body facing the center of the stator body; the depth of the stator slot is H, and the thickness of the stator body in its radial direction is W, 1:2.2 ≤ H:W ≤ 1:1.1. The above-mentioned stator structure adopts a deep slot design. 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 there is a larger space in the circumferential direction of the stator body. Therefore, the first slot body can be made wider, thereby increasing the slot filling rate of the first winding in the first slot body, making the resistance of the first winding lower and the equivalent thermal conductivity higher.

Description

Technical Field

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

[0002] High-speed motors have the advantages of small volume 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 both the teeth and the slots are relatively narrow. As the driving load increases, formed windings are usually used in high-speed motors. At this time, the advantage of the small volume of the high-speed motor itself will bring the disadvantage of low slot fill factor. The reason is that the small stator volume of the high-speed motor means that the slots for accommodating the formed windings are very narrow, and the insulation thickness of the high-voltage formed winding is determined by the voltage level and does not become thinner as the slot becomes narrower, which results in a low slot fill factor of the winding. This not only increases the resistance of the winding and increases the copper loss of the winding, but also the high proportion of insulating materials causes a decrease in the equivalent thermal conductivity of the entire winding, thereby increasing the winding temperature rise and reducing the insulation life. Summary of the Invention

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

[0004] The present invention provides the following technical solutions:

[0005] A stator structure, comprising a stator body and a first winding;

[0006] The stator body is arranged in a cylindrical shape, and a plurality of stator slots are provided on the inner side wall of the stator body. The stator slots extend along the radial direction of the stator body, and the plurality of stator slots are arranged circumferentially along the stator body;

[0007] The stator slot includes a first slot body and a second slot body that are communicated with each other. The first winding is disposed through the first slot body, and the second slot body is located on the side of the first slot body facing the center of the stator body;

[0008] Wherein, 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 own radial direction is W, 1:2.2 ≤ H:W ≤ 1:1.1, and the determination of the depth of the first slot body needs to consider the eddy current loss of the first winding. The eddy current loss coefficient is calculated by the following formula:

[0009] ;

[0010] ;

[0011] 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 between two adjacent layers of the first winding.

[0012] As a further optional solution to the stator structure, the stator body includes a yoke and a plurality of tooth portions. The yoke is arranged in a cylindrical shape, and the tooth portions extend along the radial direction of the yoke. One end of each tooth portion is connected to the inner edge of the yoke, and the plurality of tooth portions are arranged circumferentially along the yoke. A stator slot is formed between two adjacent tooth portions, and a slot wedge is arranged in the stator slot. The slot wedge is located on the side of the first slot body facing the center of the stator body;

[0013] The depth of the stator slot is calculated by the following formula:

[0014] ;

[0015] ;

[0016] ;

[0017] ;

[0018] t1 is the tooth pitch, B δ is the air-gap magnetic flux density, K Fe is the stamping lamination 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 towards the yoke, h s is the original depth of the stator slot, Z is the number of 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.

[0019] As a further optional solution to the stator structure, the second slot body has a first slot wall and a second slot wall which are oppositely arranged, and the distance between the first slot wall and the second slot wall gradually decreases in the direction away from the first slot body.

[0020] As a further optional solution to the stator structure, a protruding portion is arranged at one end of the first slot wall close to the first slot body.

[0021] As a further alternative solution to the stator structure, the second slot has a first slot wall and a second slot wall arranged oppositely, the first slot wall and the second slot wall are parallel to each other, and the width of the second slot is smaller than the width of the first slot.

[0022] As a further alternative solution to the stator structure, the first winding includes two first coils, the first coils are embedded in the first slot 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.

[0023] As a further alternative solution to 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 ends of the second coil along the axial direction of the stator body are welded to the adjacent second coils.

[0024] As a further alternative solution to the stator structure, the stator structure further includes a second winding, the second winding passes through the second slot, and the second winding is electrically connected to the first winding.

[0025] Another object of the present invention is to provide a motor.

[0026] The present invention provides the following technical solutions:

[0027] A motor includes the above-mentioned stator structure.

[0028] As a further alternative solution to the motor, the motor further includes bearings, and at least part of the bearings are located inside the perimeter of the first winding.

[0029] The embodiments of the present invention have the following beneficial effects:

[0030] 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 own radial direction is between 1:2.2 and 1:1.1. When the volume of the stator remains unchanged, the first slot for the first winding to pass through is farther from the center of the stator body, and there is a larger space along the circumference of the stator body. Therefore, the first slot can be made wider. When the voltage is constant, that is, when the thickness of the insulating layer is constant, after the slot width of the first slot increases, the proportion of the insulating layer in the first slot becomes smaller and the proportion of copper becomes larger, thereby increasing the slot fill factor of the first winding in the first slot, 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 between adjacent two 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, can be calculated through the above formula, so as to design a stator slot with appropriate dimensions.

[0031] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following provides preferred embodiments in conjunction with the accompanying drawings and makes a detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 Shows an overall structural schematic diagram of a stator structure provided by an embodiment of the present invention;

[0034] Figure 2 Shows a partial structural schematic diagram of a stator structure provided by an embodiment of the present invention;

[0035] Figure 3 Shows a partial structural schematic diagram of the stator structure after increasing the stator slot depth;

[0036] Figure 4 Shows a simulation result diagram of the eddy current loss of 32-layer conductors;

[0037] Figure 5 Shows a partial structural schematic diagram of the stator structure after increasing the stator slot depth and width;

[0038] Figure 6 Shows a simulation result diagram of the eddy current loss of 16-layer conductors;

[0039] Figure 7 Shows a curve diagram of the relationship between the eddy current loss coefficient and the winding height ratio;

[0040] Figure 8 Shows a partial structural schematic diagram of a stator structure provided by an embodiment of the present invention;

[0041] Figure 9 Shows a partial structural schematic diagram of a stator structure provided by another embodiment of the present invention;

[0042] Figure 10 Shows a partial structural schematic diagram of a stator structure provided by yet another embodiment of the present invention;

[0043] Figure 11 Shows a partial structural schematic diagram of a stator structure provided by still another embodiment of the present invention;

[0044] Figure 12 Shows an overall structural schematic diagram of a motor provided by an embodiment of the present invention.

[0045] Description of Main Component Symbols:

[0046] 10 - Stator structure; 20 - Housing; 30 - Rotor; 40 - Bearing;

[0047] 100 - Stator body; 110 - Stator slot; 111 - First slot body; 112 - Second slot body; 112a - First slot wall; 112b - Second slot wall; 112c - Protrusion; 120 - Yoke; 130 - Tooth part; 200 - First winding; 300 - Slot wedge; 400 - Second winding. Specific Embodiments

[0048] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

[0049] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. On the contrary, 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.

[0050] In the present invention, unless otherwise clearly specified and defined, the terms "installed", "connected", "connected to", "fixed" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise clearly specifically defined.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of the template herein are for the purpose of describing specific embodiments only 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.

[0053] Embodiment

[0054] This embodiment provides a stator structure 10, which is applied to a motor, especially suitable for high-speed, high-voltage, and high-power motors. Among them, a high-speed motor usually refers to a motor with a rotational speed exceeding 10,000 rpm. In addition, the power of this motor exceeds 500 kW, and a formed winding is usually adopted. The formed winding is made of flat wire, and its cross-section is rectangular.

[0055] Please refer to Figure 1 and Figure 2 simultaneously, the above-mentioned stator structure 10 includes a stator body 100 and a first winding 200.

[0056] Specifically, the stator body 100 is arranged in a cylindrical shape, and a plurality of stator slots 110 are provided on the inner side wall of the stator body 100. The stator slots 110 extend along the radial direction of the stator body 100, and the plurality of stator slots 110 are arranged circumferentially along the stator body 100.

[0057] In addition, the stator slot 110 includes a first slot body 111 and a second slot body 112 that communicate with each other. The first winding 200 passes through the first slot body 111, and the second slot body 112 is located on the side of the first slot body 111 facing the center of the stator body 100.

[0058] Among them, 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 own 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:

[0059] ;

[0060] ;

[0061] 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 between adjacent two layers of the first winding 200.

[0062] Understandably, during the process of motor design, for the stator structures 10 of different motors, the height h of the conductor, the skin depth and the phase angle between two adjacent layers of the first windings 200 are not necessarily the same and can be adjusted as needed. However, when calculating the depth H1 of the first slot 111, h,[[]] , are all regarded as constants, and the size of H1 depends on the desired eddy current loss coefficient k ACR .

[0063] In particular, when only one layer of the first winding 200 is arranged in the first slot 111, the phase angle between two adjacent layers of the first windings 200 is regarded as 0.

[0064] The above-mentioned stator structure 10 adopts a deep-slot design. The ratio of the depth of the stator slot 110 to the thickness of the stator body 100 along its own radial direction is between 1:2.2 and 1:1.1. When the stator volume remains unchanged, the first slot 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. Therefore, the first slot 111 can be made wider, thereby increasing the slot filling rate of the first winding 200 in the first slot 111, making the resistance of the first winding 200 lower and the equivalent thermal conductivity higher. At the same time, when the height of a single conductor in the first winding 200, the skin depth, and the phase angle between two adjacent layers of the first windings 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 111, can be calculated through the above formula, so as to design a stator slot 110 with appropriate dimensions.

[0065] It should be noted that the high-voltage formed winding is made of flat wires and its cross-section is rectangular. Therefore, it is required that the slots in the stator of the high-voltage motor for accommodating the formed winding must be parallel slot structures, that is, the two side edges of the stator slot 110 are parallel. Based on this premise, as Figure 3 shown, if only 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 filling rate and reduced equivalent thermal conductivity.

[0066] In addition, according to Ampere's circuital law, the leakage magnetic field in the stator slot 110 is proportional to the distance from the formed winding to the bottom of the slot. Please combine Figure 4, it can be seen from the eddy current loss simulation results of the formed winding composed of 32 layers of conductors that the closer the formed winding is to the slot opening position, the more obvious the skin effect of the internal conductors and the greater the eddy current loss. 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. This is a fatal defect for high-speed motors (the frequency is usually above 300 Hz, much higher than the low-frequency motors with a traditional 50 Hz).

[0067] Secondly, this slot structure will cause the flare at the end of the formed winding along the axis direction of the stator body 100 to become smaller, making it impossible to accommodate the bearing 40, resulting in an increase in the axial length of the motor, which will lead to a low critical speed.

[0068] Furthermore, this narrow and tall formed winding is not conducive to production and manufacturing. The bending of the nose at the end is difficult, and it is easy to cause insulation damage. Finally, when wrapping insulation on the narrow and tall formed winding, since the height of its cross-section is much larger than the width, it will lead to unstable tension of the machine-wrapped insulation tape and loose wrapping on the side of the winding, and it is easy to generate insulation voids.

[0069] As Figure 5 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, resulting in serious saturation at the narrow part of the tooth part 130. For an induction motor, it means an increase in the exciting current and a decrease in the power factor. For a permanent magnet motor, it means more permanent magnets for excitation.

[0070] In contrast, while adopting the deep slot design for the above-mentioned stator structure 10, the stator slot 110 is divided into a first slot body 111 and a second slot body 112, and the first slot body 111 farther from the center of the stator body 100 is used 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, when the thickness of the insulation layer is constant, after the slot width of the first slot body 111 increases, the proportion of the insulation layer in the first slot body 111 becomes smaller and the proportion of copper becomes larger. In addition to increasing the slot fill factor 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, it also makes the width of the first winding 200 increase and the height decrease.

[0071] On this basis, the formed winding changes from a narrow and tall type to a wide and short type, and the distance between the side of the formed winding close to the center of the stator body 100 and the bottom of the stator slot 110 decreases, so the eddy current loss caused by the slot leakage magnetic field is reduced. Specifically, please refer to Figure 6 , it can be seen from the eddy current loss simulation results of the formed winding composed of 16 layers of conductors that the eddy current loss of the wide and short formed winding is significantly smaller.

[0072] In addition, the empty second slot 112 causes the bell mouth at the end of the first winding 200 along the axis direction of the stator body 100 to increase, which can accommodate the bearing 40, reduce the axial length of the motor, increase the critical speed of the rotor 30, and enable the high-speed motor to operate safely below the first critical speed. Finally, the bent nose at the end of the first winding 200 along the axis direction of the stator body 100 is easier to bend during bending, and the tension of the machine-wrapped insulating tape is more uniform and the winding is tighter, reducing the insulation gap.

[0073] Specifically, denote the AC resistance of the first winding 200 as R AC , and the DC resistance of the first winding 200 as R DC . Given a basic winding height, denoted as H W , and at the same time set the winding height ratio as k, then:

[0074] ;

[0075] .

[0076] Generally, the short-pitch factor of the motor is taken as 5 / 6. For the entire motor winding, the above formula can be simplified as:

[0077] .

[0078] 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 as:

[0079] .

[0080] Please refer to Figure 7 , taking the full-pitch winding as an example, draw the relationship curve between the eddy current loss coefficient and the winding height ratio according to the above formula, and it can be seen that:

[0081] When the winding height ratio is 1, the eddy current loss coefficient is 1.8. When the winding height ratio doubles, the eddy current loss coefficient is 4.21, which increases by 1.34 times. Since the winding copper loss accounts for a large proportion (about 15%-30%) in the total loss of the motor, the part of the eddy current loss increased due to the increase of the winding height ratio will significantly reduce the motor efficiency.

[0082] It should be noted that during the motor design process, regardless of how the depth H1 of the first slot 111 (i.e., the height of the first winding 200) changes, the DC resistance of the first winding 200 is R DC usually remains unchanged. In the first winding 200, since the conductors are connected in parallel, the sum of the cross-sectional areas of the conductors needs to remain unchanged.

[0083] On this basis, as the depth of the first slot body 111 decreases, the dimensions of the conductors in the first winding 200 in the radial direction of the stator body 100 become smaller, so the dimensions of the conductors in the circumferential direction of the stator body 100 increase correspondingly, which means the width of the first slot body 111 increases.

[0084] Thus, 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 dimensional parameters of the stator body 100.

[0085] In some embodiments, the stator body 100 includes a yoke portion 120 and a plurality of tooth portions 130. The yoke portion 120 is arranged in a cylindrical shape. The tooth portions 130 extend in the radial direction of the yoke portion 120, and one end of each tooth portion 130 is connected to the inner edge of the yoke portion 120. The plurality of tooth portions 130 are arranged circumferentially along the yoke portion 120, and a stator slot 110 is formed between two adjacent tooth portions 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.

[0086] In addition, the depth of the stator slot 110 is calculated by the following formula:

[0087] ;

[0088] ;

[0089] ;

[0090] ;

[0091] t1 is the tooth pitch, B δ is the air-gap magnetic density, K Fe is the lamination factor of the punching sheet, B t is the magnetic density of the tooth portion 130, D i1 is the inner diameter of the stator body 100, h ex is the distance that the stator slot 110 extends towards the yoke portion 120, h s is the original depth of the stator slot 110, Z is the number of 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 in the radial direction of the stator body 100, Δh is the total thickness of the insulating layer in the first winding 200 in the radial direction of the stator body 100, Δb is the total thickness of the insulating layer in the first winding 200 in the circumferential direction of the stator body 100, and C is a constant.

[0092] It should be noted that the original depth h of the stator slot 110s 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.

[0093] In the process of motor design, on the one hand, according to the tooth pitch t1, the air-gap magnetic density B δ , the lamination factor K of the punching sheet Fe , the magnetic density B of the tooth part 130 t the tooth width required for electromagnetic design can be calculated; on the other hand, in the case of h ex = 0 (conventional stator slot 110 design scheme), 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, and the width b of the first slot body 111 s the actual tooth width can be calculated.

[0094] Since the formed winding adopts a wide and short design, the actual tooth width is usually smaller than the tooth width required for electromagnetic design. At this time, the stator slot 110 is extended a certain distance h ex towards the yoke 120, so that 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 for electromagnetic design.

[0095] Finally, according to the original depth of the stator slot 110 and the distance that the stator slot 110 extends towards the yoke 120, the depth of the stator slot 110 can be calculated.

[0096] It can be understood that after the stator slot 110 extends a certain distance h ex towards the yoke 120, the positions of the first slot body 111 and the slot wedge 300 move outwards by the same distance h ex 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.

[0097] In addition, 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 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 circumferential direction of the stator body 100 from the width 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. As mentioned above, the sum of the cross-sectional areas of all conductors needs to remain unchanged. Therefore, 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 therefrom s , and then the actual tooth width can be calculated

[0098] Similarly, in the process of motor design, for the stator structures 10 of different motors, the tooth pitch t1, the air-gap magnetic density B δ , the lamination factor K Fe , the magnetic density B of the tooth part 130 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, all parameters are regarded as constants

[0099] Please refer to Figure 8 , in some embodiments, the second slot 112 has a first slot wall 112a and a second slot wall 112b which are oppositely arranged, and the distance between the first slot wall 112a and the second slot wall 112b gradually decreases in the direction away from the first slot 111

[0100] At this time, the tooth part 130 between two adjacent second slots 112 still has sufficient width to meet the requirements of electromagnetic design

[0101] Exemplarily, protrusions are respectively arranged on one side of the first slot wall 112a and the second slot wall 112b close to the first slot 111. A limiting space for the slot wedge 300 to be inserted is formed between the two protrusions and the first winding 200 disposed in the first slot 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, preventing the first winding 200 from disengaging from the first slot 111 along the radial direction of the stator body 100

[0102] Please refer to Figure 9, alternatively, recesses may be respectively provided on the sides of the first slot wall 112a and the second slot wall 112b close to the first slot body 111, and both sides of the slot wedge 300 are respectively snapped into the two recesses.

[0103] Please refer to again Figure 2 , further, a protrusion 112c is provided at one end of the first slot wall 112a close to the first slot body 111, which can make full use of the slot opening space at the slot wedge 300 and reduce the magnetic density of the tooth part 130.

[0104] Please refer to Figure 10 , in some other embodiments, the second slot body 112 has a first slot wall 112a and a second slot wall 112b arranged oppositely, the first slot wall 112a and the second slot wall 112b are parallel to each other, and the width of the second slot body 112 is smaller than the width of the first slot body 111.

[0105] Although the second slot body 112 is closer to the center of the stator body 100, due to the smaller width of the second slot body 112, the tooth part 130 between two adjacent second slot bodies 112 still has sufficient width to meet the requirements of electromagnetic design.

[0106] In some embodiments, the first winding 200 includes two first coils. The first coils are embedded in the first slot body 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 body 111.

[0107] Since the slot opening 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 side-by-side coils in the slot width direction.

[0108] During assembly, the two first coils can be sequentially inserted into the stator slot 110 from the inner circular slot opening. The two side-by-side first coils are processed together in pairs during stretching and restoring to ensure that the end dimensions match. The first coils are individually insulated by winding and then marked in pairs, and are used in pairs during wire insertion. When wiring, the two side-by-side first coils are connected in parallel and regarded as one body.

[0109] Adopting the above wire insertion method, there are fewer solder joints and the coils have high consistency.

[0110] In some other embodiments, the first winding 200 includes a second coil. The second coil is embedded in the first slot body 111 along the axial direction of the stator body 100, and the ends of the second coil along the axial direction of the stator body 100 are welded to adjacent second coils.

[0111] Specifically, the first winding 200 adopts an open-type coil and is a single conductor along the slot width direction. During assembly, the second coil is inserted into the first slot 111 along the axial direction of the stator body 100, and is connected at the opening of the end of the second coil by means such as welding, similar to the hair pin structure of the flat wire winding of an electric vehicle.

[0112] By adopting the above-mentioned wire embedding method, along the slot width direction, the proportion of the insulating layer is small and the slot fill factor is high.

[0113] Please refer to Figure 11 , in some embodiments, the above-mentioned stator structure 10 further includes a second winding 400. The second winding 400 is disposed through the second slot 112, and the second winding 400 is electrically connected to the first winding 200, which can make full use of the area of the stator slot 110.

[0114] Among them, the second winding 400 and the first winding 200 can be connected in series or in parallel.

[0115] 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.

[0116] In summary, the above-mentioned stator structure 10 adopts a deep slot design, exchanging radial space for slot width space, while reducing the magnetic density and eddy current loss of the tooth part 130, and is more conducive to the manufacture and assembly of the coil and the stator.

[0117] Please refer to Figure 12 , this embodiment also provides a motor, including the above-mentioned stator structure 10.

[0118] In addition, the above-mentioned motor further includes a housing 20 and a rotor 30. The stator body 100 is fixedly arranged on the inner wall of the housing 20 and is arranged around the rotor 30. The rotor 30 passes through the stator body 100 and the housing 20 at the same time and is rotatably arranged on the housing 20.

[0119] Furthermore, the above-mentioned motor further includes a bearing 40, and at least part of the bearing 40 is located inside the periphery of the first winding 200.

[0120] Correspondingly, the rotor 30 is rotatably connected to the housing 20 through the bearing 40.

[0121] 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 operate safely below the first critical speed.

[0122] In all the examples shown and described here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0123] It should be noted that like reference numerals and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it is not necessary to further define and explain it in subsequent figures.

[0124] The above-described embodiments merely represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A stator structure, characterized in that, It includes a stator body and a first winding; The stator body is arranged in a cylindrical shape. A plurality of stator slots are provided on the inner side wall of the stator body. The stator slots extend along the radial direction of the stator body, and the plurality of stator slots are arranged circumferentially along the stator body; The stator slot includes a first slot body and a second slot body that are communicated with each other. The first winding is disposed through the first slot body, and the second slot body is located on the side of the first slot body facing the center of the stator body; Wherein, 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 own radial direction is W, 1:2.2 ≤ H:W ≤ 1:1.1, and the determination of the depth of the first slot body needs to consider the eddy current loss of the first winding. 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 between two adjacent layers of the first winding; The stator body includes a yoke portion and a plurality of tooth portions. The yoke portion is arranged in a cylindrical shape. The tooth portions extend along the radial direction of the yoke portion. One end of the tooth portion is connected to the inner edge of the yoke portion. The plurality of tooth portions are arranged circumferentially along the yoke portion. The stator slot is formed between two adjacent tooth portions. 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 magnetic density, K Fe is the lamination factor of the punching sheet, B t is the tooth magnetic density, D i1 is the inner diameter of the stator body, h ex is the distance that the stator slot extends towards the yoke, h s is the original depth of the stator slot, Z is the number of 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, C is a constant.

2. The stator structure according to claim 1, wherein The second slot body has a first slot wall and a second slot wall arranged oppositely. The distance between the first slot wall and the second slot wall gradually decreases in the direction away from the first slot body.

3. The stator structure according to claim 2, wherein A convex portion is provided at one end of the first slot wall close to the first slot body.

4. The stator structure according to claim 1, wherein The second slot body has a first slot wall and a second slot wall arranged oppositely. 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.

5. The stator structure according to any one of claims 1-4, 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.

6. The stator structure according to any one of claims 1-4, characterized in that, The first winding includes a second coil. The second coil is embedded in the first slot body along the axial direction of the stator body, and the ends of the second coil along the axial direction of the stator body are welded to the adjacent second coil.

7. The stator structure according to any one of claims 1-4, characterized in that, The stator structure further includes a second winding. The second winding is disposed through the second slot body, and the second winding is electrically connected to the first winding.

8. A motor, characterized in that, It includes the stator structure according to any one of claims 1-7.

9. The motor according to claim 8, characterized in that, The motor further includes a bearing, and at least part of the bearing is located inside the periphery of the first winding.

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