Stator and rotor lamination for new energy vehicle field and motor thereof

Abstract

The present application relates to a kind of new energy automobile field's stator and rotor lamination and motor thereof, including stator lamination and rotor lamination, stator lamination includes stator yoke and several stator teeth, each stator tooth is formed from the inner side of stator yoke along radial direction and extends inward, stator slot is formed between each stator tooth, stator slot is provided with opening along the radial direction of stator lamination, opening is provided with first concave arc along the radial direction of stator lamination;The outer side of rotor lamination is provided with several second concave arcs around its circumferential direction.The present application is a kind of new energy automobile field's stator and rotor lamination, by being respectively arranged in the inner side of stator lamination and the outer side of rotor lamination first concave arc and second concave arc that can reduce tooth slot torque, first concave arc and second concave arc can form unequal air gap structure between, to change the size of magnetic resistance, it is favorable for the reduction of tooth slot torque of motor, and then improve motor efficiency, motor power density and motor back electromotive force harmonic content, reduce motor cost.

Description

Technical Field

[0001] This invention relates to the field of parking motor technology for new energy vehicles, and in particular to a stator and rotor lamination and motor for use in the field of new energy vehicles. Background Technology

[0002] Currently, electric motors are widely used in the field of new energy vehicles. An electric motor is a device that converts electrical energy into mechanical energy. It utilizes the rotating magnetic field generated by the stator windings to act on the rotor, creating magnetoelectric torque. An electric motor mainly consists of a stator and a rotor. The direction of the force on a current-carrying conductor in a magnetic field depends on the direction of the current and the direction of the magnetic field lines. The working principle of an electric motor is that the magnetic field exerts a force on the current, causing the motor to rotate. The stator and rotor laminations are key components of an electric motor; their materials, inner diameter, outer diameter, and slot size directly affect the motor's energy consumption, efficiency, noise, and service life.

[0003] Cogging torque is the circumferential torque generated by the interaction between the permanent magnet and the stator teeth when the armature winding is not energized. This torque varies with the rotor position, and is therefore a pulsating torque. It originates from the resultant tangential force between the permanent magnet and the stator teeth. This tangential force always attempts to align the axis of the permanent magnet's magnetic field with the axis of the stator teeth, thus giving the rotor a tendency to be positioned at a certain location. It can also be simply understood as the principle that when the magnetic reluctance distribution in the magnetic circuit is uneven, the magnetic lines of force will always close along the magnetic path with the least magnetic reluctance, i.e., the "principle of minimum magnetic reluctance".

[0004] Currently used motors suffer from drawbacks such as low efficiency, low power density, and high back EMF harmonic content due to unreasonable stator and rotor lamination structures. Therefore, there is a need for a stator and rotor lamination and motor for use in the field of new energy vehicles. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and provide a stator and rotor lamination and motor for use in the field of new energy vehicles.

[0006] A stator and rotor lamination for use in the field of new energy vehicles includes a stator lamination and a rotor lamination. The stator lamination includes a stator yoke and a plurality of stator teeth. Each stator tooth extends radially inward from the inner periphery of the stator yoke and forms a stator slot between each stator tooth. The stator slot has an opening along the radial inner side of the stator lamination, and the opening has a first concave arc along the radial inner side of the stator lamination. The outer periphery of the rotor lamination has a plurality of second concave arcs around its circumference.

[0007] The present invention discloses a stator and rotor lamination for use in the field of new energy vehicles. By setting a first concave arc and a second concave arc on the inner side of the stator lamination and the outer side of the rotor lamination respectively, a first concave arc and a second concave arc can be formed between the first concave arc and the second concave arc, thereby changing the magnitude of magnetic reluctance. This is beneficial to reducing the cogging torque of the motor, thereby improving the motor efficiency, motor power density and motor back EMF harmonic content, and reducing motor cost.

[0008] Furthermore, the center of the first concave arc is located on the circumference of a virtual circle a, the center of which coincides with the center of the stator lamination; the diameter of the first concave arc satisfies the following formula and condition:

[0009] (A / B)*A*2=D;

[0010] 0.95 < A / B < 1;

[0011] In the formula, A is the diameter of the virtual circle a, B is the diameter of the first concave arc, and D is the inner diameter of the stator lamination.

[0012] The beneficial effect of adopting the above-mentioned further solution is that the diameter and position of the first concave arc are determined by the diameter of the virtual circle a and the inner diameter of the stator lamination. The number of the first concave arcs is the same as the number of stator slots. The diameter of the virtual circle a, the first concave arc, and the inner diameter of the stator lamination meet the above-mentioned conditional relationship, which effectively reduces the cogging torque and torque pulsation.

[0013] Furthermore, the center of the second concave arc is located on the circumference of a virtual circle b, the center of which is located on the outer diameter circumference of the stator lamination. The virtual circle b is inscribed within the complete circle of the second concave arc, and the line connecting the center of the virtual circle b and the center of the second concave arc passes through the center of the rotor lamination. The diameter of the second concave arc satisfies the following formula and condition:

[0014] E / F = 1 / 2;

[0015] 1 / 6 < E / G < 1 / 5.8;

[0016] In the formula, E is the diameter of the virtual circle b, F is the diameter of the second concave arc, and G is the outer diameter of the rotor lamination.

[0017] The beneficial effect of adopting the above-mentioned further scheme is that the number of the second concave arcs is consistent with the number of poles of the rotor laminations, and the diameters of the virtual circle b and the second concave arcs satisfy the above-mentioned conditions, which can effectively reduce the cogging torque and torque pulsation of the motor.

[0018] Furthermore, the dimensions of the stator laminations and rotor laminations satisfy the following formula:

[0019] C = (A / B) * D * (F / E) * g / 0.53;

[0020] g = 0.5 * (DG);

[0021] In the formula, C is the outer diameter of the stator lamination, and g is the value of the single-sided air gap between the stator lamination and the rotor lamination.

[0022] The beneficial effect of adopting the above-mentioned further scheme is that, based on the above-mentioned relationship conditions, the diameters of the first and second concave arcs of the stator laminations and rotor laminations, as well as the distance between them, reduce the cogging torque and torque pulsation of the motor to achieve the optimal effect.

[0023] Furthermore, the rotor lamination has a shaft hole at its center, and a plurality of magnetic slots are arranged around its center in an array; the second concave arc is correspondingly located on the outer side of the magnetic slot; the distance between the outer end of the magnetic slot and the corresponding second concave arc satisfies the following condition:

[0024] t < H < 1.1t;

[0025] In the formula, H is the distance between the outer end of the magnet slot and the corresponding second concave arc, and t is the thickness of the rotor lamination.

[0026] The beneficial effects of adopting the above-mentioned further solution are that H is the distance between the outer end of the magnet slot and the corresponding second concave arc, which is 1 to 1.1 times the thickness of the rotor lamination. This optimizes the thickness of the rotor lamination at this distance, which is beneficial to enhance the leakage flux of the magnet and thus improve the utilization rate of the magnetic flux. This thickness also facilitates the stamping production of the magnet slot. In addition, the thickness of the rotor lamination at this distance forms a closed slot, which can also reduce the cogging torque and torque pulsation of the motor. The commonly used thicknesses of rotor laminations are 0.35mm and 0.5mm. These two lamination thicknesses are relatively common. There are also lamination forms with less commonly used thicknesses, such as 0.25mm, which are also within the scope of protection of this invention.

[0027] Furthermore, the magnet slot is T-shaped; a boss is provided at the middle position of the inner end of the magnet slot, extending radially outward along the rotor lamination.

[0028] The beneficial effect of adopting the above-mentioned further solution is that the magnet slot of the rotor lamination is set in an inverted T-shaped slot manner, and a boss is set in the middle position of the T-shaped slot near the shaft hole of the rotor lamination, which plays the role of supporting and fixing the rotor magnet and isolating the magnet. The number of bosses is the same as the number of magnets.

[0029] Furthermore, the number of stator slots is 12, and the number of magnet slots is 14.

[0030] The beneficial effects of adopting the above-mentioned further scheme are that the number of magnet slots and rotor poles are the same, both being 14, and the number of stator slots is 12. The stator and rotor pole slot matching conforms to the relationship (14-12)*p=2*p in motor design, where p is an integer greater than or equal to 1 and less than or equal to 3, making the motor a fractional-slot concentrated winding motor with 14 poles and 12 slots, which conforms to the fixed pole slot matching method. This value selection conforms to the optimal design of the motor, with a winding coefficient of 0.933, effectively improving the motor efficiency.

[0031] Furthermore, the rotor lamination is provided with a number of anti-salient pole effect holes around its center, and two anti-salient pole effect holes are provided between every two magnet slots.

[0032] The beneficial effect of adopting the above-mentioned further scheme is that the saliency ratio is the quadrature axis inductance of the permanent magnet motor divided by the direct axis inductance value. Generally, the quadrature axis inductance is larger than the direct axis inductance. The anti-saliency effect is a phenomenon in which the direct axis inductance is larger than the quadrature axis inductance. To achieve this effect, the total number of holes is selected as an integer multiple of the number of magnetic poles. In this invention, it is preferably twice the number of holes, but it can also be selected as a multiple of 4 or 6.

[0033] Furthermore, the rotor laminations are provided with several rivet points around their center, with one rivet point between every two magnet slots.

[0034] The beneficial effect of adopting the above-mentioned further solution is that there are rivet points between the two magnet slots in the middle position of the rotor lamination. The number of rivet points is the same as the number of rotor magnetic poles, which is used to stack and fix multiple rotor laminations together to form a whole. The number of rivet points can be equal to the number of magnetic poles or half the number of magnetic poles.

[0035] The present invention also provides an electric motor, including rotor laminations and stator laminations as described above; and further including magnets, wherein the aspect ratio of the magnets is T / W = 4.5 to 5.5.

[0036] The beneficial effect of adopting the above-mentioned further scheme is that the thickness-to-width ratio of the magnet is T / W = 4.5 to 5.5, which can improve the cost-effectiveness of motor design while meeting the maximum allowable demagnetization of the motor.

[0037] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0038] Figure 1 This is a schematic diagram illustrating the fit between the stator and rotor laminations of the present invention;

[0039] Figure 2 This is a schematic diagram of the stator lamination structure of the present invention;

[0040] Figure 3 This is a schematic diagram of the structure of the splicing component of the present invention;

[0041] Figure 4 This is a schematic diagram of the rotor lamination structure of the present invention;

[0042] Figure 5 This is a schematic diagram showing the dimensions of the rotor laminations of the present invention;

[0043] Figure 6 This is a schematic diagram of the internal structure of the motor of the present invention;

[0044] Figure 7 This is a simplified schematic diagram of the rotor structure of the present invention;

[0045] Figure 8 This is a schematic diagram of the structure of the magnet of the present invention.

[0046] In the diagram: 10. Stator lamination; 11. Stator yoke; 12. Stator tooth; 13. Stator slot; 14. Opening; 15. First concave arc; 20. Rotor lamination; 21. Second concave arc; 22. Shaft hole; 23. Magnet slot; 24. Boss; 25. Anti-salient pole effect hole; 26. Riveting point; 30. Magnet. Detailed Implementation

[0047] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0048] It should be understood that in the description of this application, the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing this application and for simplifying the description, and 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. Therefore, they should not be construed as limitations on this application. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. That is, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, unless otherwise stated, "a plurality of" means two or more.

[0049] It should be noted that, in the description of this application, unless otherwise expressly specified and limited, the terms "set up," "connected," "linked," and "hollow" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0050] Please see Figure 1 The stator and rotor laminations 20 used in the field of new energy vehicles in this embodiment include stator laminations 10 and rotor laminations 20.

[0051] For details, please refer to Figure 2 and Figure 3 The stator lamination 10 includes a stator yoke 11 and 12 stator teeth 12, each stator tooth 12 extending radially inward from the inner periphery of the stator yoke 11; preferably, the stator lamination 10 can be formed by splicing and welding 12 T-shaped splicing pieces; a stator groove 13 is formed between each stator tooth 12 of the stator lamination 10, the stator groove 13 is provided with an opening 14 along the radial inner side of the stator lamination 10, and the opening 14 is provided with a first concave arc 15 along the radial inner side of the stator lamination 10;

[0052] More specifically, the center of the first concave arc 15 is located on the circumference of a virtual circle a, the center of which coincides with the center of the stator lamination 10; the diameter of the first concave arc 15 satisfies the following formula and condition:

[0053] (A / B)*A*2=D;

[0054] 0.95 < A / B < 1;

[0055] In the formula, A is the diameter of the virtual circle a, B is the diameter of the first concave arc 15, and D is the inner diameter of the stator lamination 10.

[0056] For details, please refer to Figure 4 and Figure 5 The outer periphery of the rotor lamination 20 is provided with a plurality of second concave arcs 21 around its circumference; the center of the second concave arc 21 is located on the circumference of a virtual circle b, the center of the virtual circle b is located on the outer diameter circumference of the stator lamination 10, the virtual circle b is inscribed in the complete circle of the second concave arc 21, and the line connecting the center of the virtual circle b and the center of the second concave arc 21 passes through the center of the rotor lamination 20; the diameter of the second concave arc 21 satisfies the following formula and condition:

[0057] E / F = 1 / 2;

[0058] 1 / 6 < E / G < 1 / 5.8;

[0059] In the formula, E is the diameter of the virtual circle b, F is the diameter of the second concave arc 21, and G is the outer diameter of the rotor lamination 20.

[0060] The stator and rotor laminations 20 of the present invention for use in the field of new energy vehicles have a first concave arc 15 and a second concave arc 21 respectively provided on the inner side of the stator lamination 10 and the outer side of the rotor lamination 20 to reduce cogging torque. The first concave arc 15 and the second concave arc 21 can form an unequal air gap structure, thereby changing the magnitude of magnetic reluctance, which is beneficial to reducing the cogging torque of the motor, thereby improving the motor efficiency, motor power density and motor back EMF harmonic content, and reducing motor cost.

[0061] In the preferred embodiment, see [reference] Figure 2 and Figure 5 To optimize the reduction of cogging torque and torque pulsation in the stator lamination 10 and rotor lamination 20, the diameters of the first concave arc 15 and the second concave arc 21, as well as the distance between them, satisfy the following formula:

[0062] C = (A / B) * D * (F / E) * g / 0.53;

[0063] g = 0.5 * (DG);

[0064] In the formula, C is the outer diameter of stator lamination 10, and g is the value of the single-sided air gap between stator lamination 10 and rotor lamination 20.

[0065] In the preferred embodiment, the diameter A of the virtual circle a is 29.5-31.5 mm; the outer diameter C of the stator lamination 10 is 86-89 mm; and the inner diameter D of the stator lamination 10 is 59-60 mm.

[0066] Preferably, the diameter A of the virtual circle a is 30 mm, the diameter B of the first concave arc 15 is 30.4 mm, the outer diameter C of the stator lamination 10 is 88.2 mm, the inner diameter D of the stator lamination 10 is 59.2 mm, the diameter E of the virtual circle b is 10 mm, the diameter F of the second concave arc 21 is 20 mm, and the outer diameter G of the rotor lamination 20 is 58.4 mm. In this embodiment, the number of stator slots 13 is 12, and the number of magnet slots 23 is 14.

[0067] The number of magnet slots 23 is the same as the number of rotor poles, both being 14. The number of stator slots 13 is 12. The stator and rotor pole slot matching conforms to the relationship (14-12)*p=2*p in motor design, where p is an integer greater than or equal to 1 and less than or equal to 3. This makes the motor a fractional-slot concentrated winding motor with 14 poles and 12 slots, which conforms to the fixed pole slot matching method. This value selection conforms to the optimal design of the motor, and the winding coefficient is 0.933, which effectively improves the motor efficiency.

[0068] In the preferred embodiment, see [reference] Figure 4 The rotor lamination 20 has a shaft hole 22 at its center, and 14 magnetic slots 23 are arranged in an array around its center. The second concave arc 21 is correspondingly arranged on the outer side of the magnetic slot 23. In order to optimize the length of the magnetic slot 23, the distance between the outer end of the magnetic slot 23 and the corresponding second concave arc 21 satisfies the following condition:

[0069] t < H < 1.1t;

[0070] In the formula, H is the distance between the outer end of the magnet slot 23 and the corresponding second concave arc 21, and t is the thickness of the rotor lamination 20;

[0071] The rotor laminations 20 commonly have thicknesses of 0.35mm and 0.5mm. These two lamination thicknesses are relatively common. There are also laminations with less common thicknesses, such as 0.25mm, which are also within the scope of protection of this invention.

[0072] In this preferred embodiment, the magnet slot 23 is T-shaped; a boss 24 is provided at the middle position of the inner end of the magnet slot 23, extending radially outward along the rotor lamination 20; the magnet slot 23 of the rotor lamination 20 is an inverted T-shaped slot, and the boss 24 is provided at the middle position of the T-shaped slot of the rotor lamination 20 near the shaft hole 22, which serves to support and fix the rotor magnet 30 and to isolate the magnets; the number of bosses 24 is the same as the number of magnets 30.

[0073] In the preferred embodiment, the rotor lamination 20 is provided with a plurality of anti-salient pole effect holes 25 around its center, and two anti-salient pole effect holes 25 are provided between every two magnet slots 23; the salient pole ratio is the quadrature axis inductance of the permanent magnet motor divided by the direct axis inductance value. Generally, the quadrature axis inductance is larger than the direct axis inductance. The anti-salient pole effect is a phenomenon in which the direct axis inductance is larger than the quadrature axis inductance. To achieve this effect, the total number of holes is selected as an integer multiple of the number of magnetic poles. The present invention preferably selects two times, but it can also select a multiple of 4 or 6.

[0074] In a preferred embodiment, the rotor lamination 20 is provided with a plurality of rivet points 26 around its center, and a rivet point 26 is provided between every two magnet slots 23; a rivet point 26 is provided between two magnet slots 23 in the middle position of the rotor lamination 20, and the number of rivet points 26 is the same as the number of rotor magnetic poles, which is used to stack and fix multiple rotor laminations 20 together to form a whole. The number of rivet points 26 can be equal to the number of magnetic poles, or it can be half the number of magnetic poles.

[0075] Please see Figure 6 and Figure 7 The motor of this embodiment includes rotor laminations 20 and stator laminations 10 as described above. Multiple rotor laminations 20 are stacked to form a rotor, and multiple stator laminations 10 are stacked to form a stator. The stator winding connection of the motor is a six-phase (double three-phase) winding structure.

[0076] Please see Figure 8 The motor in this embodiment also includes a magnet 30. In order to improve the cost-effectiveness of the motor design while meeting the maximum allowable demagnetization of the motor, the thickness-to-width ratio of the magnet 30 is preferably T / W = 4.5 to 5.5. In this embodiment, the thickness-to-width ratio of the magnet 30 is preferably 5.

[0077] Compared to existing technologies, this invention reduces cogging torque by setting a first concave arc and a second concave arc on the inner side of the stator lamination and the outer side of the rotor lamination, respectively. The first and second concave arcs can form unequal air gap structures, thereby changing the magnitude of magnetic reluctance. This is beneficial for reducing cogging torque in the motor, thereby improving motor efficiency, power density, and back EMF harmonic content, and reducing motor cost. The motor of this invention has advantages such as high efficiency, high power density, low cost, low cogging torque, and low back EMF harmonic content.

[0078] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A stator and rotor lamination for use in the field of new energy vehicles, characterized in that, include: A stator lamination includes a stator yoke and a plurality of stator teeth. Each stator tooth extends radially inward from the inner periphery of the stator yoke, forming a stator groove between the teeth. The stator groove has an opening along the radially inner side of the stator lamination, and the opening has a first concave arc along the radially inner side of the stator lamination. The center of the first concave arc is located on the circumference of a virtual circle a, and the center of the virtual circle a coincides with the center of the stator lamination. The diameter of the first concave arc satisfies the following formula and condition: (A / B)·A·2=D; 0.95 < A / B < 1; In the formula, A is the diameter of the virtual circle a, B is the diameter of the first concave arc, and D is the inner diameter of the stator lamination; A rotor lamination has a plurality of second concave arcs circumferentially arranged on its outer periphery. The centers of the second concave arcs are located on the circumference of a virtual circle b, the center of which is located on the outer diameter circumference of the stator lamination. The virtual circle b is inscribed in the complete circle of the second concave arcs. The line connecting the center of the virtual circle b and the center of the second concave arcs passes through the center of the rotor lamination. The diameter of the second concave arcs satisfies the following formula and condition: E / F = 1 / 2; 1 / 6 < E / G < 1 / 5.8; In the formula, E is the diameter of the virtual circle b, F is the diameter of the second concave arc, and G is the outer diameter of the rotor lamination.

2. The stator and rotor laminations for use in the field of new energy vehicles according to claim 1, characterized in that, The dimensions of the stator laminations and rotor laminations satisfy the following formula: C=(A / B)·D·(F / E)·g / 0.53; g = 0.5·(DG); In the formula, C is the outer diameter of the stator lamination, and g is the value of the single-sided air gap between the stator lamination and the rotor lamination.

3. The stator and rotor laminations for use in the field of new energy vehicles according to claim 2, characterized in that, The rotor lamination has a shaft hole at its center, and a plurality of magnetic slots are arranged around its center in an array; the second concave arc is correspondingly located on the outer side of the magnetic slot; the distance between the outer end of the magnetic slot and the corresponding second concave arc satisfies the following condition: t < H < 1.1t; In the formula, H is the distance between the outer end of the magnet slot and the corresponding second concave arc, and t is the thickness of the rotor lamination.

4. The stator and rotor laminations for use in the field of new energy vehicles according to claim 3, characterized in that, The magnet slot is T-shaped; a boss is provided at the middle position of the inner end of the magnet slot, extending radially outward along the rotor lamination.

5. The stator and rotor laminations for use in the field of new energy vehicles according to claim 3, characterized in that, The number of stator slots is 12, and the number of magnet slots is 14.

6. The stator and rotor laminations for use in the field of new energy vehicles according to claim 3, characterized in that, The rotor laminations are provided with several anti-salient pole effect holes around their center, and two anti-salient pole effect holes are provided between every two magnet slots.

7. The stator and rotor laminations for use in the field of new energy vehicles according to claim 3, characterized in that, The rotor laminations are provided with several rivet points around their center, with one rivet point between every two magnet slots.

8. An electric motor, characterized in that, It includes rotor laminations and stator laminations as described in any one of claims 1 to 7; it also includes magnets, wherein the aspect ratio of the magnets is T / W = 4.5 to 5.5.

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