Stator lamination, stator core, stator, electric machine and compressor

Abstract

The application provides a kind of stator lamination, stator core, stator, motor and compressor, and the motor belongs to energy-saving motor. Wherein, the stator lamination includes annular yoke part and first stator tooth and second stator tooth arranged alternately along the circumferential direction of annular yoke part;The side of first stator tooth away from annular yoke part has first pole shoe, and the side of second stator tooth away from annular yoke part has second pole shoe;The end face of first pole shoe away from annular yoke part is defined as first face, and the end face of second pole shoe away from annular yoke part is defined as second face, and first face and second face are located on the same cylindrical surface;First pole shoe has first end along the circumferential direction of annular yoke part, and the radial thickness of first end is T1, second pole shoe has second end along the circumferential direction of annular yoke part, and the radial thickness of second end is t1;t1<T1. The application can reduce the cogging torque fluctuation, rely on harmonic to suppress electromagnetic vibration noise by mutual offset, and improve the operation comfort of machine.

Description

Technical Field

[0001] This invention belongs to the field of motor technology, specifically relating to a stator lamination, a stator core, a stator, a motor, and a compressor. The motor is an energy-saving electric motor. Background Technology

[0002] As core energy-consuming components of air conditioning systems, variable frequency scroll and rotary compressors require their driving permanent magnet synchronous motors to be upgraded towards higher efficiency, lower vibration, lower noise, wider speed range, and lower cost mass production. Currently, the mainstream household variable frequency air conditioner compressors are equipped with 12-slot, 8-pole fractional-slot concentrated winding permanent magnet synchronous motors. With the improvement of energy efficiency standards, the industry has begun to explore a new pole-slot ratio of 12 slots and 10 poles in order to achieve higher power density and efficiency.

[0003] For existing 12-slot, 10-pole permanent magnet synchronous motors, the stator teeth pole shoes all adopt a design with equal radial thickness, and the air gap magnetic permeability is periodically and uniformly distributed along the circumference. When the rotor magnetic poles sweep across the stator teeth, they will excite radial electromagnetic force waves with concentrated amplitude, resulting in large fluctuations in cogging torque. This causes coupled vibration in the compressor pump body, generating resonance and howling in the 1~8kHz frequency range, which is sensitive to human hearing, reducing the overall operating comfort of the machine. Therefore, this invention studies and designs a stator lamination, stator core, stator, motor, and compressor. The motor is an energy-saving type. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the pole shoes of each stator tooth adopt the same radial thickness design in the prior art, which leads to large fluctuations in tooth groove torque. Thus, a stator lamination, stator core, stator, motor and compressor are provided, and the motor is an energy-saving motor.

[0005] To address the aforementioned problems, this invention provides a stator lamination comprising an annular yoke and alternating first and second stator teeth arranged circumferentially along the annular yoke; the first stator teeth have a first pole shoe on the side facing away from the annular yoke, and the second stator teeth have a second pole shoe on the side facing away from the annular yoke; the end face of the first pole shoe facing away from the annular yoke is defined as a first face, and the end face of the second pole shoe facing away from the annular yoke is defined as a second face, the first face and the second face being located on the same cylindrical surface; the first pole shoe has a first end portion along the circumferential direction of the annular yoke, the radial thickness of the first end portion being T1, and the second pole shoe has a second end portion along the circumferential direction of the annular yoke, the radial thickness of the second end portion being t1; t1 <T1。

[0006] In some implementations, 0.5 ≤ t1 / T1 ≤ 0.75.

[0007] In some embodiments, the tooth body of the second stator tooth has a tapered section, the circumferential width of which gradually decreases from the annular yoke toward the second pole shoe.

[0008] In some embodiments, in a cross section perpendicular to the axis of the stator lamination, the tapered section has two symmetrically arranged planar sidewalls, the included angle between the two planar sidewalls being 2α, where 3°≤α≤9°.

[0009] In some embodiments, the tooth body of the second stator tooth further has a first straight segment, the width of which remains consistent from the annular yoke toward the second pole shoe; the first straight segment is located between the tapered section and the second pole shoe to connect the tapered section and the second pole shoe.

[0010] In some embodiments, the tooth body of the first stator tooth has a second straight segment, the circumferential width of which remains consistent from the annular yoke toward the first pole shoe.

[0011] In some embodiments, when the tooth body of the second stator tooth has a tapered section, and the circumferential width of the tapered section gradually decreases from the annular yoke towards the second pole shoe, the circumferential width of the second straight segment is B; the radial length of the second straight segment from the annular yoke towards the first pole shoe is L; wherein, in a section perpendicular to the axis of the stator lamination, the minimum circumferential width of the tapered section is b2, and the tapered section has two symmetrically arranged planar sidewalls, the included angle between the two planar sidewalls is 2α; b2 = BA × L × tanα, and the value range of the coefficient A is: 0.14 ≤ A ≤ 0.16;

[0012] And / or, in a cross section perpendicular to the axis of the stator lamination, the maximum circumferential width of the tapered section is b1, where b1 = B;

[0013] And / or, from the annular yoke toward the second pole shoe, the radial length of the tapered section is L1, 0.7≤L1 / L≤0.8.

[0014] In some embodiments, a stator slot is formed between the first stator tooth and the adjacent second stator tooth. The stator slot has an opening on the side opposite to the annular yoke. The opening has opposing first and second sidewalls along the circumference of the annular yoke. The radial end face of the first end forms the first sidewall, and the radial end face of the second end forms the second sidewall.

[0015] In some embodiments, the present invention also provides a stator core comprising the stator laminations described in any of the preceding embodiments.

[0016] In some embodiments, the present invention also provides a stator comprising any of the stator laminations described above; or comprising the stator core described above; wherein a first winding is wound on the first stator tooth, and a second winding is wound on the second stator tooth.

[0017] In some embodiments, when the first stator tooth has a second straight segment whose circumferential width remains consistent from the annular yoke towards the first pole shoe, and the second stator tooth has a tapered section whose circumferential width gradually decreases from the annular yoke towards the second pole shoe, the number of turns of the coil in the first winding is N1, and the number of turns of the coil in the second winding is N2; in a cross-section perpendicular to the axis of the stator lamination, the conducting cross-sectional area of ​​a single coil in the first winding is S1, and the conducting cross-sectional area of ​​a single coil in the second winding is S2, N1*S1 <N2*S2。

[0018] In some embodiments, when a stator slot is formed between the first stator tooth and the adjacent second stator tooth, the stator slot has an opening on the side opposite to the annular yoke, and the opening has opposing first and second sidewalls along the circumference of the annular yoke, with the radial end face of the first end forming the first sidewall and the radial end face of the second end forming the second sidewall, the distance between the first sidewall and the second sidewall is H, and the minimum distance between the first winding and the second winding is h, where 0.5 ≤ h / H ≤ 0.8.

[0019] In some embodiments, the number of the first stator teeth and the second stator teeth are both two or more. The first winding on each of the first stator teeth forms a first connection structure by wiring, and the second winding on each of the second stator teeth forms a second connection structure by wiring. One of the first connection structure and the second connection structure is a delta connection structure, and the other is a star connection structure.

[0020] In some embodiments, the stator tooth corresponding to the star connection structure in the first stator tooth and the second stator tooth is defined as the A stator tooth, and the winding on the A stator tooth is called the A winding. Each of the A windings is divided into three groups, namely the U1 winding, the V1 winding and the W1 winding. The U1 winding, the V1 winding and the W1 winding are staggered in sequence along the circumference of the annular yoke. Each U1 winding is connected in series to form a U1 branch, each V1 winding is connected in series to form a V1 branch, and each W1 winding is connected in series to form a W1 branch. One end of each of the U1 branch, the V1 branch and the W1 branch is electrically connected to form the star midpoint, and the other end of each branch forms a terminal.

[0021] In some embodiments, the stator tooth corresponding to the triangular connection structure in the first stator tooth and the second stator tooth is defined as the B stator tooth, and the winding on the B stator tooth is called the B winding. Each of the B windings is divided into three groups, namely the U2 winding, the V2 winding, and the W2 winding. The U2 winding, the V2 winding, and the W2 winding are staggered in sequence along the circumference of the annular yoke. Each U2 winding is connected in series to form a U2 branch, each V2 winding is connected in series to form a V2 branch, and each W2 winding is connected in series to form a W2 branch. One end of the U2 branch is electrically connected to one end of the V2 branch to form a first terminal. The other end of the U2 branch is electrically connected to one end of the W2 branch to form a second terminal. The other end of the V2 branch is electrically connected to the other end of the W2 branch to form a third terminal.

[0022] In some embodiments, when the stator tooth corresponding to the star connection structure in the first stator tooth and the second stator tooth is defined as the A stator tooth, and the winding on the A stator tooth is called the A winding; each of the A windings is divided into three groups, namely the U1 winding, the V1 winding and the W1 winding, the U1 winding, the V1 winding and the W1 winding are staggered in sequence along the circumference of the annular yoke, the U1 windings are connected in series to form the U1 branch, the V1 windings are connected in series to form the V1 branch, the W1 windings are connected in series to form the W1 branch, one end of the U1 branch, the V1 branch and the W1 branch are electrically connected to form the star midpoint, and the other ends of the three branches are respectively formed as terminals, the first terminal is connected in parallel with the other end of the V1 branch, the second terminal is connected in parallel with the other end of the U1 branch, and the third terminal is connected in parallel with the other end of the W1 branch.

[0023] In some embodiments, the present invention also provides an electric motor comprising the stator laminations described in any of the preceding claims; or comprising the stator core described in the preceding claims; or comprising the stator described in the preceding claims.

[0024] In some embodiments, the motor further includes a rotor having two or more magnetic poles, the polarities of which alternate sequentially along the circumference of the rotor; a stator slot is formed between each first stator tooth and an adjacent second stator tooth; wherein the number of magnetic poles is 10 and the number of stator slots is 12.

[0025] In some embodiments, the present invention also provides a compressor comprising the stator laminations described in any of the preceding claims; or the stator core described in the preceding claims; or the stator described in the preceding claims; or the motor described in the preceding claims.

[0026] The stator lamination, stator core, stator, motor, and compressor provided by this invention have the following beneficial effects:

[0027] 1. This invention designs the radial thickness of the pole shoe ends of adjacent stator teeth to be inconsistent. The radial thickness T1 of the first pole shoe end is relatively large, resulting in a smaller equivalent air gap and a larger air gap permeability between the first stator tooth and the rotor. The radial thickness t1 of the adjacent second pole shoe end is relatively small, resulting in a larger equivalent air gap and a smaller air gap permeability. This creates a high-low air gap permeability distribution in the circumferential direction of the motor. When the same magnetic pole sweeps across two adjacent pole shoes with different radial thicknesses, the resulting pulsating magnetic flux is strong and weak, and the pulsating components cancel each other out, thereby weakening the pulsating magnetic pull acting on the rotor, reducing cogging torque fluctuations, and further suppressing electromagnetic vibration noise through harmonic cancellation, thus improving the overall operating comfort of the machine. When stator laminations are applied to the motor, the motor is an energy-saving motor.

[0028] 2. The second stator tooth of the present invention adopts a trapezoidal tooth design with a large tooth cavity, which can wind more round copper wires, increase the conductor current-carrying area, reduce the DC resistance of the winding, reduce steady-state DC copper loss, and improve motor efficiency.

[0029] 3. This invention uses two sets of star-delta windings in parallel operation. In low-speed operation, the star branch dominates the output, resulting in low starting current and low loss. In high-speed operation, the delta branch is adapted to field weakening control, which has a higher back EMF utilization rate and significantly reduces the additional field weakening loss. Attached Figure Description

[0030] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the stator lamination structure of the present invention;

[0032] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0033] Figure 3 This is a schematic diagram illustrating the structure of the first stator tooth;

[0034] Figure 4 This is a schematic diagram illustrating the structure of the second stator tooth;

[0035] Figure 5 This is a schematic diagram reflecting the trapezoidal shape of the tapered section on the second stator tooth;

[0036] Figure 6 This is a schematic diagram illustrating the assembly of the stator and rotor of the present invention;

[0037] Figure 7This is a schematic diagram illustrating the connection between the triangular connection structure and the star connection structure of the present invention.

[0038] The attached figures are labeled as follows:

[0039] 1. Annular yoke; 2. First stator tooth; 3. Second stator tooth; 4. Stator slot; 5. First winding; 6. Second winding; 7. First terminal; 8. Second terminal; 9. Third terminal; 20. First face; 21. First pole shoe; 22. Second straight segment; 30. Second face; 31. Second pole shoe; 40. Slot opening; 71. U1 winding; 81. V1 winding; 91. W1 winding; 72. U2 winding; 82. V2 winding; 92. W2 winding; 211, First end; 311, Second end; 401, First sidewall; 402, Second sidewall; 2a, First B chamfered section; 2b, Second B chamfered section; 3a, Tapered section; 3b, First straight section; 3c, First A chamfered section; 3d, Second A chamfered section; 7a, U1 branch; 8a, V1 branch; 9a, W1 branch; 7b, U2 branch; 8b, V2 branch; 9b, W2 branch; 3a1, First outer sidewall; 3a2, Second outer sidewall; 3a3, Third straight section; 3a4, Fourth straight section; 7a1, Other end of U1 branch; 8a1, Other end of V1 branch; 9a1, Other end of W1 branch. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0042] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0043] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0044] like Figure 1-4 As shown, according to an embodiment of the present invention, a stator lamination is provided, comprising an annular yoke 1 and first stator teeth 2 and second stator teeth 3 alternately arranged circumferentially along the annular yoke 1. The side of the first stator tooth 2 facing away from the annular yoke 1 has a first pole shoe 21, and the side of the second stator tooth 3 facing away from the annular yoke 1 has a second pole shoe 31. The end face of the first pole shoe 21 facing away from the annular yoke 1 is defined as a first face 20, and the end face of the second pole shoe 31 facing away from the annular yoke 1 is defined as a second face 30. The first face 20 and the second face 30 are located on the same cylindrical surface. The first pole shoe 21 has a first end portion 211 along the circumferential direction of the annular yoke 1, and the radial thickness of the first end portion 211 is T1. The second pole shoe 31 has a second end portion 311 along the circumferential direction of the annular yoke 1, and the radial thickness of the second end portion 311 is t1. Wherein, t1... <T1。

[0045] In the above example, the present invention designs the radial thicknesses of the pole shoe ends of adjacent stator teeth to be inconsistent. The radial thickness T1 of the end of the first pole shoe 21 is relatively large, resulting in a smaller equivalent air gap and a larger air gap permeability between the first stator tooth 2 and the rotor. The radial thickness t1 of the end of the adjacent second pole shoe 31 is relatively small, resulting in a larger equivalent air gap and a smaller air gap permeability. This creates a high-low air gap permeability distribution in the circumferential direction of the motor. When the same magnetic pole sweeps across two adjacent pole shoes with different radial thicknesses, the resulting pulsating magnetic flux is strong and weak, and the pulsating components cancel each other out, thereby weakening the pulsating magnetic pull acting on the rotor, reducing cogging torque fluctuations, and further suppressing electromagnetic vibration noise by mutually canceling harmonics, thus improving the overall operating comfort of the machine. When stator laminations are applied to the motor, the motor is an energy-saving motor.

[0046] It should be noted that the aforementioned first pole shoe 21 is symmetrically arranged at both ends along the circumference of the annular yoke 1. The first end 211 is the outer end of the first pole shoe 21 along the circumference of the annular yoke 1, and the radial thickness of the first pole shoe 21 gradually increases from the first end 211 towards the tooth body of the first stator tooth 2. The aforementioned second pole shoe 31 is symmetrically arranged at both ends along the circumference of the annular yoke 1. The second end 311 is the outer end of the second pole shoe 31 along the circumference of the annular yoke 1, and the radial thickness of the second pole shoe 31 gradually increases from the second end 311 towards the tooth body of the second stator tooth 3.

[0047] In some implementations, 0.5 ≤ t1 / T1 ≤ 0.75. Preferably, t1 / T1 = 0.68.

[0048] In the above example, if t1 / T1 < 0.5, the radial thickness of the second pole piece 31 is too small, the equivalent air gap permeability is too low, the permeability difference is too large, and the periodic fluctuation of the air gap magnetic flux density will induce new second-order harmonics. Furthermore, the mechanical stiffness of the pole piece is insufficient, and warping deformation is likely to occur during stamping. If t1 / T1 is greater than 0.75, the permeability difference of the first pole piece 21 is insufficient, the harmonic cancellation effect is low, and the noise reduction target of differentiated permeability modulation cannot be achieved.

[0049] In some implementations, such as Figure 4 As shown, the tooth body of the aforementioned second stator tooth 3 has a tapered section 3a, and the circumferential width of the tapered section 3a gradually decreases from the annular yoke 1 toward the second pole shoe 31.

[0050] In the above example, the design of the tapered section 3a on the second stator tooth 3 can increase the slot cavity space of the stator slot 4, allowing more turns of enameled round copper wire to be arranged in the slot, increasing the effective cross-sectional area of ​​the conductor, reducing the overall DC resistance of the winding, and effectively reducing copper loss.

[0051] In some implementations, such as Figure 5As shown, in a cross-section perpendicular to the axis of the stator lamination, the aforementioned tapered section 3a has opposing first outer walls 3a1 and second outer walls 3a2, which are symmetrically arranged about the centerline of the second stator tooth 3. The ends of the first outer walls 3a1 and 3a2 closest to the center of the stator lamination are connected by a third straight segment 3a3, and the ends of the first outer walls 3a1 and 3a2 furthest from the center of the stator lamination are connected by a fourth straight segment 3a4. The first outer wall 3a1, the third straight segment 3a3, the second outer wall 3a2, and the fourth straight segment 3a4 form a trapezoidal shape, with the length of the third straight segment 3a3 being less than the length of the fourth straight segment 3a4. Due to this trapezoidal design, the aforementioned second stator tooth 3 is sometimes referred to as a trapezoidal tooth.

[0052] In some implementations, such as Figure 4 As shown, in a cross-section perpendicular to the axis of the stator lamination, the tapered section 3a has two symmetrically arranged planar sidewalls, with an included angle of 2α, where 3°≤α≤9°. Preferably, α=4°.

[0053] In the above example, if α < 3°, the angle is too small, the expansion effect of stator slot 4 is small, and the advantage of reducing copper loss of delta winding cannot be realized. If α > 9°, the angle is too large, the contraction is too great, the magnetic cross-sectional area of ​​the tooth tip is greatly reduced, the magnetic tip is prone to magnetic saturation, iron loss increases, and the tooth tip structure is too narrow, which makes it easy for lamination to warp during the stamping process.

[0054] In some implementations, such as Figure 4 As shown, the tooth body of the aforementioned second stator tooth 3 also has a first straight segment 3b, the width of which remains consistent from the annular yoke 1 toward the second pole shoe 31. The first straight segment 3b is located between the tapered section 3a and the second pole shoe 31 to connect the tapered section 3a and the second pole shoe 31.

[0055] In the example above, by setting the first straight segment 3b, the cross-sectional area of ​​the main magnetic circuit on the second stator tooth 3 can be ensured to be sufficient, thus avoiding magnetic saturation of the tooth root of the second stator tooth 3.

[0056] In some implementations, such as Figure 4 As shown, the aforementioned first straight segment 3b is connected to the second pole shoe 31 through the first A chamfered segment 3c, and the end of the aforementioned tapered segment 3a that is away from the first straight segment 3b is connected to the annular yoke 1 through the second A chamfered segment 3d.

[0057] In some implementations, such as Figure 3As shown, the tooth body of the aforementioned first stator tooth 2 has a second straight segment 22, the circumferential width of which remains consistent from the annular yoke 1 toward the first pole shoe 21. Therefore, the first stator tooth 2 is also referred to as a square tooth in some contexts.

[0058] In the above example, the first stator tooth 2 forms a square tooth, which helps to regularize the stator slot 4 cavity and ensures that the lower conductors are arranged neatly. Among them, the square tooth has a regular tooth shape and a larger coupling area in the thick pole shoe air gap, which can stabilize the fundamental air gap magnetic field and reduce low-speed torque pulsation.

[0059] In some implementations, such as Figure 3 As shown, one end of the second straight segment 22 is connected to the first pole shoe 21 via the first B chamfered segment 2a, and the other end of the second straight segment 22 is connected to the annular yoke 1 via the second B chamfered segment 2b. It should be noted that while the trapezoidal tooth design of the second stator tooth 3 can increase the area of ​​the stator slot 4 cavity, if all stator teeth adopt a trapezoidal tooth design, it will cause a general contraction of the magnetic circuit at the tooth tip, making the tooth tip area more prone to magnetic saturation, increasing iron loss, and thus failing to achieve the desired efficiency improvement. The first stator tooth 2 forms a square tooth design with equal width and sufficient magnetic circuit at the tooth tip. Its alternating arrangement with the trapezoidal teeth helps to balance the circumferential magnetic flux density distribution of the stator and avoid localized overheating.

[0060] In some embodiments, when the tooth body of the second stator tooth 3 has a tapered section 3a, and the circumferential width of the tapered section 3a gradually decreases from the annular yoke 1 towards the second pole shoe 31, the circumferential width of the second straight segment 22 is B; the radial length of the second straight segment 22 from the annular yoke 1 towards the first pole shoe 21 is L. In a cross-section perpendicular to the axis of the stator lamination, the minimum circumferential width of the tapered section 3a is b2. The tapered section 3a has two symmetrically arranged planar sidewalls, and the included angle between the two planar sidewalls is 2α; b2 = BA × L × tanα, and the coefficient A ranges from 0.14 ≤ A ≤ 0.16.

[0061] In the example above, A is a proportional coefficient characterizing the degree of tooth width contraction in the tapered section 3a. The formula b2 = BA × L × tanα, as described above, is beneficial for defining the dimensions of the trapezoidal tooth.

[0062] In some embodiments, the maximum width of the tapered section 3a in a cross section perpendicular to the axis of the stator lamination is b1, where b1 = B.

[0063] In the above example, the root of the tooth is the position where the stator tooth is subjected to force. The uniform width ensures that the circumferential mechanical stiffness is consistent after the iron core is stacked, and the vibration distribution of the motor is balanced, avoiding the generation of local resonance noise.

[0064] In some embodiments, the radial length of the aforementioned tapered section 3a in the direction from the annular yoke 1 to the second pole shoe 31 is L1, 0.7≤L1 / L≤0.8, to ensure that the magnetic field lines at the top of the second stator tooth 3 pass through, and to avoid local magnetic saturation at the top of the second stator tooth 3.

[0065] In some implementations, such as Figure 2 As shown, a stator slot 4 is formed between the aforementioned first stator tooth 2 and the adjacent second stator tooth 3. The stator slot 4 has a slot opening 40 on the side opposite to the annular yoke 1, and the slot opening 40 has opposing first sidewalls 401 and second sidewalls 402 along the circumference of the annular yoke 1. The radial end face of the aforementioned first end 211 forms the first sidewall 401, and the radial end face of the second end 311 forms the second sidewall 402.

[0066] In the above example, the radial end face of the first end 211 corresponds to the first sidewall 401 of the slot 40, and the radial end face of the second end 311 corresponds to the second sidewall 402 of the slot 40.

[0067] like Figure 3 As shown, the aforementioned first stator tooth 2 is a square tooth with a thick pole shoe design. The radial sidewalls on both sides of the tooth body are completely parallel, and the overall structure is a standard rectangular square structure. The width of the tooth root is consistent with the width of the tooth tip. The pole shoe extends outward from the tooth tip and is thickened, with a larger radial thickness. The end face of the pole shoe is a smooth arc surface, without any noise reduction auxiliary slots. The thicker pole shoe can stabilize the fundamental air gap magnetic field waveform, ensuring stable magnetic flux coupling and smooth starting torque under low-speed starting conditions of the star winding. The slot 40 is surrounded by the square tooth sidewalls, and the slot cavity space is regular, which is suitable for the regular arrangement of round copper wires.

[0068] like Figure 4 As shown, the aforementioned second stator tooth 3 is a trapezoidal tooth with a thin pole shoe design. The width of the tooth base is consistent with the width of the tooth base of the adjacent first stator tooth 2. The tooth body slopes inward from the tooth base to the two side walls on both sides of the tooth tip, forming a trapezoidal structure where the tooth tip is smaller than the tooth base. A thin pole shoe extends from the tooth tip, and the overall thickness of the pole shoe is less than the thickness of the pole shoe of the first stator tooth 2. The trapezoidal structure allows for a larger open space at the top of the slot 40, enabling more turns of enameled round copper wire to be arranged in the slot. This increases the effective cross-sectional area of ​​the conductor, reduces the overall DC resistance of the winding, and effectively reduces copper loss. The thin pole shoe alters the local air gap permeability, creating a permeability difference with the adjacent thick pole shoe, thus achieving harmonic cancellation.

[0069] In some embodiments, the present invention also provides a stator core comprising any of the stator laminations described above.

[0070] In some embodiments, the present invention also provides a stator comprising any of the stator laminations described above; or comprising the stator core described above. For example... Figure 6As shown, a first winding 5 is wound on the first stator tooth 2, and a second winding 6 is wound on the second stator tooth 3.

[0071] In some embodiments, when the tooth body of the first stator tooth 2 has a second straight segment 22, and the circumferential width of the second straight segment 22 remains consistent from the annular yoke 1 towards the first pole shoe 21, and the tooth body of the second stator tooth 3 has a tapering segment 3a, and the circumferential width of the tapering segment 3a gradually decreases from the annular yoke 1 towards the second pole shoe 31, the number of turns of the coil in the first winding 5 is N1, and the number of turns of the coil in the second winding 6 is N2. In a cross-section perpendicular to the stator lamination axis, the conducting cross-sectional area of ​​a single coil in the first winding 5 is S1, and the conducting cross-sectional area of ​​a single coil in the second winding 6 is S2, N1*S1 <N2*S2。

[0072] In the above example, when the conduction cross-sectional area of ​​a single coil in the first winding 5 and the second winding 6 is equal, that is, S1 equals S2, more turns of enameled round copper wire can be arranged in the slot cavity at the second stator tooth 3, the effective cross-sectional area of ​​the conductor increases, the overall DC resistance of the winding decreases, and copper loss can be effectively reduced.

[0073] In some implementations, such as Figure 6 As shown, when a stator slot 4 is formed between the first stator tooth 2 and the adjacent second stator tooth 3, the stator slot 4 has a slot opening 40 on the side away from the annular yoke 1. The slot opening 40 has opposing first sidewalls 401 and second sidewalls 402 along the circumference of the annular yoke 1. When the radial end face of the aforementioned first end 211 forms the first sidewall 401 and the radial end face of the second end 311 forms the second sidewall 402, the distance between the first sidewall 401 and the second sidewall 402 is H, and the minimum distance between the first winding 5 and the second winding 6 is h, 0.5≤h / H≤0.8.

[0074] In the above example, the distance between the first sidewall 401 and the second sidewall 402 is the width of the slot 40. The present invention ensures that the minimum distance h between the first winding 5 and the second winding 6 satisfies: 0.5≤h / H≤0.8, so that the minimum distance h between the first winding 5 and the second winding 6 is not too large, which would result in too few turns of the winding coil, and the effective cross-sectional area of ​​the winding would be too small, thus increasing copper loss; it also ensures that the minimum distance h between the first winding 5 and the second winding 6 is not too small, which would affect the insertion of the subsequent spacer.

[0075] In some embodiments, there are two or more first stator teeth 2 and second stator teeth 3. The first windings on each first stator tooth 2 are connected to form a first connection structure, and the second windings on each second stator tooth 3 are connected to form a second connection structure. One of the first connection structure and the second connection structure is a delta connection structure, and the other is a star connection structure.

[0076] In the example above, the stator has two independent concentrated windings, forming a delta connection and a star connection, respectively. These two windings operate in parallel. At low speeds, the star connection dominates the output, resulting in low starting current and low losses. At high speeds, the delta connection is adapted for field weakening control, leading to higher back EMF utilization and significantly reduced additional field weakening losses. The delta and star connections operate in parallel in phase, balancing low-speed starting efficiency with high-speed field weakening efficiency.

[0077] In some implementations, such as Figure 7 As shown, the stator teeth corresponding to the star connection structure in the first stator tooth 2 and the second stator tooth 3 are defined as A stator teeth, and the windings on the A stator teeth are called A windings. Each A winding is divided into three groups: U1 winding 71, V1 winding 81, and W1 winding 91. The three U1 windings 71, V1 winding 81, and W1 winding 91 are staggered sequentially along the circumference of the annular yoke 1. Each U1 winding 71 is connected in series to form U1 branch 7a, each V1 winding 81 is connected in series to form V1 branch 8a, and each W1 winding 91 is connected in series to form W1 branch 9a. One end of each of the three branches is electrically connected to form the star midpoint, and the other ends of each branch form a terminal.

[0078] In the example above, the U1 winding 71, V1 winding 81 and W1 winding 91 are connected in the manner described above to form the aforementioned star connection structure.

[0079] In some implementations, such as Figure 7 As shown, the stator teeth corresponding to the triangular connection structure in the first stator tooth 2 and the second stator tooth 3 are defined as B stator teeth, and the windings on the B stator teeth are called B windings. Each B winding is divided into three groups: U2 winding 72, V2 winding 82, and W2 winding 92. The three windings are staggered along the circumference of the annular yoke 1. Each U2 winding 72 is connected in series to form U2 branch 7b, each V2 winding 82 is connected in series to form V2 branch 8b, and each W2 winding 92 is connected in series to form W2 branch 9b. One end of U2 branch 7b is electrically connected to one end of V2 branch 8b to form the first terminal 7. The other end of U2 branch 7b is electrically connected to one end of W2 branch 9b to form the second terminal 8. The other end of V2 branch 8b is electrically connected to the other end of W2 branch 9b to form the third terminal 9.

[0080] In the example above, the U2 winding 72, V2 winding 82 and W2 winding 92 are connected in the manner described above to form the aforementioned triangular connection structure.

[0081] In some implementations, such as Figure 7As shown, the aforementioned first terminal 7 is connected in parallel with the other end 8a1 of the V1 branch, forming a V-phase parallel terminal. The second terminal 8 is connected in parallel with the other end 7a1 of the U1 branch, forming a U-phase parallel terminal. The third terminal 9 is connected in parallel with the other end 9a1 of the W1 branch, forming a W-phase parallel terminal. This allows for parallel driving of both star and delta connection structures in the same phase, eliminating the need for separate power supplies and saving on the number of drive power supplies required.

[0082] In some implementations, the aforementioned V-phase parallel terminals, U-phase parallel terminals, and W-phase parallel terminals are electrically connected one-to-one with the corresponding phase control terminals of the frequency converter drive controller. Specifically, the star connection structure dominates the output in low-speed operation, while the delta connection structure adapts to field weakening control in high-speed operation, thus optimizing motor operating efficiency across the entire range.

[0083] In some embodiments, the aforementioned stator tooth A is the first stator tooth 2, and the stator tooth B is the second stator tooth 3. That is, the windings on each of the first stator teeth 2 form a star connection structure, and the windings on each of the second stator teeth 3 form a delta connection structure. Specifically, the first stator tooth 2 is a square tooth with thick pole shoes, which, combined with the star connection structure, is the mainstay for low-speed operation. The star winding has a high no-load back EMF, responsible for the low-frequency start-up and low-speed continuous operation of the air conditioning compressor. The square tooth has a regular tooth shape, and the thick pole shoes have a larger air gap coupling area, which can stabilize the fundamental air gap magnetic field and reduce low-speed torque pulsation. The second stator tooth 3 is a trapezoidal tooth with thin pole shoes, combined with the delta connection structure, which is the mainstay for high-speed operation. The delta connection weakens the magnetic field at high speed, aiming for low winding copper losses.

[0084] In some embodiments, the aforementioned stator lamination is a one-piece stamped structure of annular silicon steel. A stator slot 4 is formed between the first stator tooth 2 and the adjacent second stator tooth 3. The number of stator slots 4 is 12, suitable for a 12-slot, 10-pole built-in permanent magnet compressor motor. The aforementioned first stator tooth 2 and second stator tooth 3 each have 6 teeth, totaling 12, namely tooth 1, tooth 2, tooth 3, tooth 4, ..., tooth 12. The aforementioned first stator tooth 2 has an odd number of teeth (1, 3, 5, 7, 9, 11) and is a square tooth with a thick pole shoe structure. The aforementioned second stator tooth 3 has an even number of teeth (2, 4, 6, 8, 10, 12) and is a trapezoidal tooth with a wider bottom and narrower top, with a thin pole shoe structure. The first winding 5 and the second winding 6 mentioned above are both made of enameled round copper wire with single-tooth concentrated winding. The wire diameter is selected as φ0.5mm~1.2mm. According to the slot cavity space, the number of turns of the coil on the second stator tooth 3 is more than the number of turns of the coil on the first stator tooth 2.

[0085] The aforementioned star connection structure includes phases U1, V1, and W1. Phase U1: The windings on teeth 1 and 7 are connected in series. Phase V1: The windings on teeth 3 and 9 are connected in series. Phase W1: The windings on teeth 5 and 11 are connected in series. The neutral points at the ends of the three-phase windings U1, V1, and W1 are short-circuited, forming a star connection.

[0086] The aforementioned delta connection structure includes phases U2, V2, and W2. Phase U2: The windings on teeth 2 and 8 are connected in series. Phase V2: The windings on teeth 4 and 10 are connected in series. Phase W2: The windings on teeth 6 and 12 are connected in series. U2, V2, and W2 are connected end-to-end to form a delta connection. In the parallel connection structure, the input terminals of U1 and U2 are connected in parallel, the input terminals of V1 and V2 are connected in parallel, and the input terminals of W1 and W2 are connected in parallel. Both sets of windings are synchronously connected to the frequency converter drive controller.

[0087] In some embodiments, the present invention also provides an electric motor comprising any of the stator laminations described above; or comprising the stator core described above; or comprising the stator described above.

[0088] In some embodiments, the aforementioned motor further includes a rotor having two or more magnetic poles, the polarities of which alternate sequentially along the circumference of the rotor. Each first stator tooth 2 and adjacent second stator tooth 3 forms a stator slot 4. The number of magnetic poles is 10, and the number of stator slots 4 is 12, thus forming a 12-slot, 10-pole motor.

[0089] In some embodiments, each of the aforementioned magnetic poles is a permanent magnet pole. The aforementioned motor is a permanent magnet synchronous motor.

[0090] In some embodiments, the present invention also provides a compressor comprising any of the stator laminations described above; or comprising the stator core described above; or comprising the stator described above; or comprising the motor described above.

[0091] In some implementations, the aforementioned compressor is an air conditioning compressor.

[0092] The first stator tooth 2 of this invention is a square tooth, and the regular slot cavity ensures that the lower layer of conductors are arranged neatly. The second stator tooth 3 is a trapezoidal tooth with a large slot cavity, which can wind more turns of round copper wire, increase the conductor current-carrying area, reduce the DC resistance of the winding, reduce steady-state DC copper loss, and improve motor efficiency. The open slot of the second stator tooth 3 is suitable for multi-layer winding, reducing the additional high-frequency AC losses caused by conductor cross-stacking.

[0093] Formula for calculating motor efficiency: η = ( - ) / 100%.

[0094] Main total loss calculation formula: = + + .

[0095] in, For input power, This represents the total loss. Therefore, it can be seen that reducing motor losses is the only way to improve motor efficiency; reducing copper losses (P_cu1) and iron losses (P_Fe) can improve motor efficiency.

[0096] This invention employs a star-delta winding system operating in parallel. In low-speed operation, the star branch dominates the output, resulting in low starting current and low losses. In high-speed operation, the delta branch is adapted for field weakening control, leading to higher back EMF utilization and significantly reduced additional field weakening losses. Adjacent thick and thin pole shoes are arranged alternately, and the effective magnetic permeability of the air gap changes periodically on the circumference. When the rotor poles sweep across adjacent sets of teeth, the high-order harmonics generated are out of phase, and the harmonic components cancel each other out, significantly reducing cogging torque and radial electromagnetic excitation force. The air gap magnetic flux density waveform distortion rate is reduced, and torque pulsation under load conditions is significantly decreased, reducing compressor pump body impact vibration and suppressing high-frequency howling noise.

[0097] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0098] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A stator lamination, characterized in that: It includes an annular yoke (1) and a first stator tooth (2) and a second stator tooth (3) arranged alternately along the circumference of the annular yoke (1); the first stator tooth (2) has a first pole shoe (21) on the side away from the annular yoke (1), and the second stator tooth (3) has a second pole shoe (31) on the side away from the annular yoke (1); the end face of the first pole shoe (21) on the side away from the annular yoke (1) is defined as the first face (20), and the end face of the second pole shoe (31) on the side away from the annular yoke (1) is defined as the second face (30), and the first face (20) and the second face (30) are located on the same cylindrical surface; The first pole shoe (21) has a first end portion (211) along the circumference of the annular yoke (1), and the radial thickness of the first end portion (211) is T1. The second pole shoe (31) has a second end portion (311) along the circumference of the annular yoke (1), and the radial thickness of the second end portion (311) is t1. <T1。 2. The stator lamination according to claim 1, characterized in that: 0.5≤t1 / T1≤0.

75.

3. The stator lamination according to claim 1, characterized in that: The tooth body of the second stator tooth (3) has a tapered section (3a), the circumferential width of which gradually decreases from the annular yoke (1) toward the second pole shoe (31).

4. The stator lamination according to claim 3, characterized in that: In a cross section perpendicular to the axis of the stator lamination, the tapered section (3a) has two symmetrically arranged planar sidewalls, the included angle between the two planar sidewalls being 2α, where 3°≤α≤9°.

5. The stator lamination according to claim 3 or 4, characterized in that: The tooth body of the second stator tooth (3) also has a first straight segment (3b), the circumferential width of which is consistent from the annular yoke (1) toward the second pole shoe (31); the first straight segment (3b) is located between the tapered section (3a) and the second pole shoe (31) to connect the tapered section (3a) and the second pole shoe (31).

6. The stator lamination according to any one of claims 1-4, characterized in that: The tooth body of the first stator tooth (2) has a second straight segment (22), and the circumferential width of the second straight segment (22) is consistent from the annular yoke (1) toward the first pole shoe (21).

7. The stator lamination according to claim 6, characterized in that: When the tooth body of the second stator tooth (3) has a tapered section (3a), and the circumferential width of the tapered section (3a) gradually decreases from the annular yoke (1) towards the second pole shoe (31), the circumferential width of the second straight segment (22) is B; the radial length of the second straight segment (22) from the annular yoke (1) towards the first pole shoe (21) is L; wherein, In a cross section perpendicular to the axis of the stator lamination, the minimum circumferential width of the tapered section (3a) is b2. The tapered section (3a) has two symmetrically arranged planar sidewalls, and the included angle between the two planar sidewalls is 2α. b2 = BA × L × tanα, and the value range of the coefficient A is: 0.14 ≤ A ≤ 0.

16. And / or, in a section perpendicular to the axis of the stator lamination, the maximum circumferential width of the tapered section (3a) is b1, b1=B; And / or, from the annular yoke (1) toward the second pole shoe (31), the radial length of the tapered section (3a) is L1, 0.7≤L1 / L≤0.

8.

8. The stator lamination according to any one of claims 1-4 and 7, characterized in that: A stator groove (4) is formed between the first stator tooth (2) and the adjacent second stator tooth (3). The stator groove (4) has a slot (40) on the side away from the annular yoke (1). The slot (40) has a first sidewall (401) and a second sidewall (402) opposite to each other along the circumference of the annular yoke (1). The radial end face of the first end (211) forms the first sidewall (401), and the radial end face of the second end (311) forms the second sidewall (402).

9. A stator core, characterized in that: Includes the stator laminations according to any one of claims 1-8.

10. A stator, characterized in that: Includes the stator laminations according to any one of claims 1-8; or includes the stator core according to claim 9; The first stator tooth (2) is wound with a first winding (5), and the second stator tooth (3) is wound with a second winding (6).

11. The stator according to claim 10, characterized in that: When the tooth body of the first stator tooth (2) has a second straight segment (22), the circumferential width of the second straight segment (22) remains consistent from the annular yoke (1) toward the first pole shoe (21), and the tooth body of the second stator tooth (3) has a tapered section (3a), the circumferential width of the tapered section (3a) gradually decreases from the annular yoke (1) toward the second pole shoe (31), The number of turns of the coil in the first winding (5) is N1, and the number of turns of the coil in the second winding (6) is N2; in a cross section perpendicular to the axis of the stator lamination, the conducting cross-sectional area of ​​a single coil in the first winding (5) is S1, and the conducting cross-sectional area of ​​a single coil in the second winding (6) is S2, N1*S1 <N2*S2。 12. The stator according to claim 10 or 11, characterized in that: When a stator slot (4) is formed between the first stator tooth (2) and the adjacent second stator tooth (3), the stator slot (4) has a groove (40) on the side away from the annular yoke (1), and the groove (40) has opposing first sidewalls (401) and second sidewalls (402) along the circumference of the annular yoke (1), with the radial end face of the first end (211) forming the first sidewall (401) and the radial end face of the second end (311) forming the second sidewall (402), The distance between the first sidewall (401) and the second sidewall (402) is H, and the minimum distance between the first winding (5) and the second winding (6) is h, where 0.5 ≤ h / H ≤ 0.

8.

13. The stator according to any one of claims 10-12, characterized in that: The number of the first stator tooth (2) and the second stator tooth (3) are both two or more. The first winding (5) on each of the first stator teeth (2) forms a first connection structure by wiring, and the second winding (6) on each of the second stator teeth (3) forms a second connection structure by wiring. Among them, one of the first connection structure and the second connection structure is a delta connection structure and the other is a star connection structure.

14. The stator according to claim 13, characterized in that: The stator teeth corresponding to the star connection structure in the first stator teeth (2) and the second stator teeth (3) are defined as A stator teeth, and the windings on the A stator teeth are called A windings. Each A winding is divided into three groups, namely U1 winding (71), V1 winding (81) and W1 winding (91). The three U1 windings (71), V1 windings (81) and W1 windings (91) are staggered in sequence along the circumference of the annular yoke (1). Each U1 winding (71) is connected in series to form a U1 branch (7a), each V1 winding (81) is connected in series to form a V1 branch (8a), and each W1 winding (91) is connected in series to form a W1 branch (9a). One end of each of the three U1 branches (7a), V1 branches (8a) and W1 branches (9a) is electrically connected to form the star midpoint, and the other end of each of them forms a terminal.

15. The stator according to claim 13, characterized in that: The stator teeth corresponding to the triangular connection structure in the first stator teeth (2) and the second stator teeth (3) are defined as B stator teeth, and the windings on the B stator teeth are called B windings. Each B winding is divided into three groups, namely U2 winding (72), V2 winding (82) and W2 winding (92). The three U2 windings (72), V2 windings (82) and W2 windings (92) are staggered in sequence along the circumference of the annular yoke (1). Each U2 winding (72) is connected in series to form a U2 branch (7b), each V2 winding (82) is connected in series to form a V2 branch (8b), and each W2 winding (92) is connected in series to form a W2 branch (9b). One end of the U2 branch (7b) is electrically connected to one end of the V2 branch (8b) to form a first terminal (7); the other end of the U2 branch (7b) is electrically connected to one end of the W2 branch (9b) to form a second terminal (8); the other end of the V2 branch (8b) is electrically connected to the other end of the W2 branch (9b) to form a third terminal (9).

16. The stator according to claim 15, characterized in that: When the stator teeth corresponding to the star connection structure in the first stator tooth (2) and the second stator tooth (3) are defined as A stator teeth, and the windings on the A stator teeth are called A windings; each of the A windings is divided into three groups, namely U1 winding (71), V1 winding (81) and W1 winding (91), the three U1 windings (71), V1 windings (81) and W1 windings (91) are staggered in sequence along the circumference of the annular yoke (1), each U1 winding (71) is connected in series to form U1 branch (7a), each V1 winding (81) is connected in series to form V1 branch (8a), each W1 winding (91) is connected in series to form W1 branch (9a), one end of each of the three U1 branch (7a), V1 branch (8a) and W1 branch (9a) is electrically connected to form the star midpoint, and the other ends of each of the three form terminals respectively. The first terminal (7) is connected in parallel with the other end (8a1) of the V1 branch, the second terminal (8) is connected in parallel with the other end (7a1) of the U1 branch, and the third terminal (9) is connected in parallel with the other end (9a1) of the W1 branch.

17. An electric motor, characterized in that: It includes the stator laminations as described in any one of claims 1-8; or the stator core as described in claim 9; or the stator as described in any one of claims 10-16.

18. The motor according to claim 17, characterized in that: It also includes a rotor, which has two or more magnetic poles, and the polarity of each magnetic pole alternates sequentially along the circumference of the rotor; a stator slot (4) is formed between each of the first stator teeth (2) and the adjacent second stator teeth (3); The number of magnetic poles is 10, and the number of stator slots (4) is 12.

19. A compressor, characterized in that: It includes the stator laminations of any one of claims 1-8; or the stator core of claim 9; or the stator of any one of claims 10-16; or the motor of claim 17 or 18.

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