A rotor structure, permanent magnet motor and application

Abstract

The present invention provides a rotor structure, a permanent magnet motor and an application. According to the rotor structure of the present invention, it includes a rotor core and a plurality of permanent magnets; wherein, a plurality of sets of slots are circumferentially formed on the end surface of the rotor core; each permanent magnet is correspondingly embedded in each slot, the permanent magnet contains heavy rare earth elements, and the permanent magnets are divided into a diffusion region and a non-diffusion region according to the content of heavy rare earth elements. The diffusion region contains heavy rare earth elements with a mass percentage of g%, and the non-diffusion region contains heavy rare earth elements with a mass percentage of g`, g`<g. A first magnetic isolation bridge is provided between the permanent magnets. When the relevant parameters meet the relationship defined by the present invention, it is possible to improve the local anti-demagnetization ability of the permanent magnet on the premise of ensuring the demagnetization reliability and not increasing the volume of the permanent magnet, thereby improving the anti-demagnetization ability of the rotor, reducing the rotor cost, and meeting the application requirements of the motor performance on the whole machine. The present invention also provides a permanent magnet motor and an application.

Description

Technical Field

[0001] The present invention belongs to the technical field of motors, and in particular relates to a rotor structure, a permanent magnet motor and applications. Background Art

[0002] In the current household air conditioning compressor market, fixed-speed models are gradually being phased out, and variable-frequency motors have become the mainstream technology. These motors typically use permanent magnet motors, in which the rotor is excited by permanent magnets. Due to the high power density of current permanent magnet motors and the need to reduce costs, the rotor's permanent magnets' resistance to demagnetization has weakened. Irreversible demagnetization of permanent magnets can affect the performance and reliability of the motor and compressor, severely impacting the product's lifespan. Furthermore, with the rising price of rare earth materials, the price of rare earth permanent magnets and the cost of motors have skyrocketed.

[0003] To ensure reliable motor operation, cost reduction for permanent magnets and motors is imperative. The fundamental reason for the price increase of permanent magnets is the rising price of heavy rare earth elements (HREs). The HRE content affects the magnet's remanence and coercivity. Coercivity directly reflects its resistance to demagnetization. For magnets of the same size and used in the same motor, magnets with low coercivity have poor rotor demagnetization resistance, resulting in a higher risk of rotor demagnetization and more pronounced demagnetization. Therefore, to meet the performance requirements of the motor within the entire machine, the rotor structure needs to be redesigned. Summary of the Invention

[0004] The present invention aims to solve at least one of the above-mentioned technical problems in the prior art. To this end, the present invention provides a rotor structure.

[0005] The present invention also provides a permanent magnet motor, which includes the rotor structure.

[0006] The present invention also provides a compressor comprising the rotor structure.

[0007] The present invention also provides a refrigeration device, which includes the permanent magnet motor or the compressor.

[0008] A first aspect of the present invention provides a rotor structure comprising a rotor core and a plurality of permanent magnets, wherein:

[0009] A plurality of slots are provided on the end surface of the rotor core along the circumferential direction;

[0010] Each of the permanent magnets is correspondingly embedded in each of the slots. The permanent magnets contain heavy rare earth elements, and are divided into a diffusion zone and a non-diffusion zone according to the content of the heavy rare earth elements.

[0011] The diffusion zone contains heavy rare earth elements in a mass percentage of g%.

[0012] In the non-diffusion region, it contains heavy rare earth elements with a mass percentage of g`%.

[0013] The relationship between g` and g is: g`<g.

[0014] A first magnetic isolation bridge is provided between the permanent magnets, and y1 is the thickness of the first magnetic isolation bridge.

[0015] L max , B ,

[0025] ,

[0024] ,

[0023] ,

[0022] , , max , A , , , is the maximum length of the diffusion region along the width direction of the permanent magnet.

[0016] W max is the maximum length of the diffusion region along the thickness direction of the permanent magnet.

[0017] D is the outer diameter of the rotor core.

[0018] T is the stack thickness of the rotor core.

[0019] P is the number of pole pairs of the permanent magnet.

[0020] Among the above parameters, y1, L max , W max , D, T and P simultaneously satisfy the relational expressions of formula (A) and formula (B):

[0021] At least, the technical solution of the rotor structure in the technical solution of the present invention has the following beneficial effects:

[0022] In formula (A) and formula (B), 0.01≤k A ≤2.00, 0.01≤k B ≤2.00.

[0023] One technical solution in the technical solution of the rotor structure of the present invention has at least the following beneficial effects:

[0024] The rotor structure of the present invention includes a rotor core and multiple permanent magnets. Specifically:

[0025] On the end face of the rotor core, multiple groups of slots are circumferentially opened, and each permanent magnet is correspondingly embedded in each slot. The permanent magnet contains heavy rare earth elements. The permanent magnet is divided into a diffusion region and a non-diffusion region according to the content of the heavy rare earth elements. Among them, in the diffusion region, it contains heavy rare earth elements with a mass percentage of g%, and in the non-diffusion region, it contains heavy rare earth elements with a mass percentage of g`, and g`<g. A first magnetic isolation bridge is provided between the permanent magnets, with a thickness of y1. The maximum length of the diffusion region along the width direction of the permanent magnet is L max , and the maximum length of the diffusion region along the thickness direction of the permanent magnet is W maxThe outer diameter of the rotor core is D, the thickness of the rotor core is T, and the number of permanent magnet pole pairs is P. Among the above parameters, y1, L max 、W max When , D, T and P satisfy the relationship of formula (A) and formula (B) at the same time, the local anti-demagnetization ability of the permanent magnet can be improved without increasing the volume of the permanent magnet while ensuring the demagnetization reliability, thereby improving the anti-demagnetization ability of the rotor, reducing the rotor cost, and meeting the application requirements of the motor performance in the whole machine.

[0026] The rotor structure of the present invention sets the key parameters y1, L max 、W max , D, T and P are combined with the coating position of the heavy rare earth coating to form a formula. If the overall anti-demagnetization ability of the motor structure design is poor, in order to ensure reliability, the coating position (length, width, area) is required to be larger; on the contrary, if the overall anti-demagnetization ability of the motor structure design is good, the coating position (length, width, area) can be designed to be relatively small.

[0027] The magnetic isolation bridge can, to a certain extent, act as a magnetic barrier. By installing a magnetic isolation bridge, the possibility of magnetic circuit disorder and magnetic leakage problems within the rotor structure can be effectively reduced. Specifically, the smaller the width of the magnetic isolation bridge, the greater the reverse magnetic field experienced by the areas on both sides of the permanent magnet (under the same conditions, demagnetization is more likely). Furthermore, the magnetic isolation bridge primarily affects the magnitude of the motor's magnetic leakage coefficient. The larger the magnetic leakage coefficient, the less affected the permanent magnet is by the reverse magnetic field, and the better the demagnetization resistance.

[0028] The diffusion zone refers to a layer of heavy rare earth coating applied to the surface of the permanent magnet substrate during the permanent magnet manufacturing process. Different formulations can be formulated to meet specific requirements. For higher demagnetization resistance requirements, a higher heavy rare earth content is required. Applying two different concentrations of heavy rare earth formulations to the permanent magnet substrate creates diffusion zones with varying demagnetization resistance. After the heavy rare earth coating is applied, it undergoes a high-temperature treatment to allow the heavy rare earth elements to diffuse into the permanent magnet, forming a stable grain boundary state.

[0029] In order to adapt to the application environment of household air conditioners, the permanent magnets of variable frequency motors are mostly NdFeB permanent magnets containing heavy rare earth elements and high coercivity. 14 B-based permanent magnet materials are primarily composed of neodymium, iron, and boron. To achieve different performance characteristics, heavy rare earth metals such as dysprosium and terbium can be used to replace some of the neodymium in permanent magnets. Heavy rare earth metals refer to those with atomic numbers ranging from 64 to 71, plus element 39: gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium.

[0030] y1, L max 、W max The units of , D and T are all millimeters.

[0031] The thickness of the magnetic isolation bridge may range from 0.4 mm to 0.9 mm.

[0032] The maximum length L of the diffusion zone along the width of the permanent magnet max The range can be 1mm to 15mm.

[0033] The maximum length W of the diffusion zone along the thickness direction of the permanent magnet max The range can be 1mm to 3.5mm.

[0034] The outer diameter D of the rotor core may be in the range of 60 mm to 90 mm.

[0035] The thickness T of the rotor core may be in the range of 50 mm to 120 mm.

[0036] The number of permanent magnet pole pairs P may range from 2 to 5.

[0037] According to some embodiments of the present invention, the shape of the permanent magnet comprises a cuboid.

[0038] For the convenience of description, the permanent magnet is divided into length direction, width direction and thickness direction.

[0039] According to some embodiments of the present invention, the diffusion regions are distributed along the width direction of the permanent magnet to form a plurality of diffusion regions.

[0040] According to some embodiments of the present invention, the diffusion region may be distributed along the width direction of the permanent magnet to form one diffusion region.

[0041] According to some embodiments of the present invention, the diffusion regions may be distributed along the width direction of the permanent magnet to form two diffusion regions.

[0042] According to some embodiments of the present invention, the diffusion regions may be distributed along the width direction of the permanent magnet to form a plurality of diffusion regions.

[0043] According to some embodiments of the present invention, the distribution shape of the diffusion region includes a U-shaped structure.

[0044] According to some embodiments of the present invention, the distribution shape of the diffusion region includes a quadrangular structure.

[0045] According to some embodiments of the present invention, the distribution shape of the diffusion region includes a three-strip structure.

[0046] According to some embodiments of the present invention, the diffusion region includes a first diffusion region and / or a second diffusion region.

[0047] According to some embodiments of the present invention, the first diffusion region contains g1% by mass of heavy rare earth elements, and the second diffusion region contains g2% by mass of heavy rare earth elements.

[0048] According to some embodiments of the present invention, the mass percentage of heavy rare earth elements in the first diffusion region is g1%, and g1% is 1.0% to 2.0%.

[0049] According to some embodiments of the present invention, the mass percentage of heavy rare earth elements in the first diffusion region is g1%, and g1% is 1.05% to 2.00%.

[0050] According to some embodiments of the present invention, the mass percentage of heavy rare earth elements in the second diffusion region is g2%, and g2% is 0.5% to 1.4%.

[0051] According to some embodiments of the present invention, the mass percentage of heavy rare earth elements in the second diffusion region is g2%, and g2% is 0.59% to 1.25%.

[0052] According to some embodiments of the present invention, the mass percentage of the heavy rare earth element in the non-diffusion region is 0 to 0.6%.

[0053] According to some embodiments of the present invention, the mass percentage of the heavy rare earth element in the non-diffusion region is 0 to 0.55%.

[0054] According to some embodiments of the present invention, the mass percentage of heavy rare earth elements in the non-diffusion region is 0 to 0.53%.

[0055] According to some embodiments of the present invention, the slot is V-shaped.

[0056] According to some embodiments of the present invention, the V-shaped opening faces the stator of the motor.

[0057] Because heavy rare earth magnets have lower intrinsic coercivity than conventional rare earth magnets, their direct use can reduce the motor's demagnetization resistance. However, V-shaped slots enhance the motor's demagnetization resistance. The V-shaped slots also achieve a magnetic field concentration effect, increasing the main magnetic flux and, in turn, the back EMF, ultimately boosting motor efficiency.

[0058] According to some embodiments of the present invention, a second magnetic isolation bridge is further provided between each of the permanent magnets.

[0059] According to some embodiments of the present invention, the second magnetic isolation bridge is provided at the bottom of the V-shape.

[0060] According to some embodiments of the present invention, y2 is the thickness of the second magnetic isolation bridge.

[0061] L 1max is the maximum length of the first diffusion region along the width direction of the permanent magnet.

[0062] W 1max is the maximum length of the first diffusion region along the thickness direction of the permanent magnet.

[0063] L 2max is the maximum length of the second diffusion region along the width direction of the permanent magnet.

[0064] W 2max is the maximum length of the second diffusion region along the thickness direction of the permanent magnet.

[0065] Formula (1) to formula (4) are:

[0066]

[0067]

[0068] When the diffusion region includes a first diffusion region and a second diffusion region, y1, y2, L 1max 、L 2max 、W 1max 、W 2max , D, T and P simultaneously satisfy the relationships of equations (1) to (4).

[0069] In formulas (1) to (4), 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, and 0.02≤k4≤1.37.

[0070] L 1max 、L 2max 、W 1max 、W 2max It is the coating position defined in the present invention.

[0071] y1, y2, L 1max 、L 2max 、W 1max 、W 2max The units of , D and T are all millimeters.

[0072] According to some embodiments of the present invention, the thickness of the second magnetic isolation bridge is y2.

[0073] The maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max .

[0074] The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max .

[0075] The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max .

[0076] The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max .

[0077] When the diffusion region only has the first diffusion region or the second diffusion region, y1, y2, L 1max 、L 2max 、W 1max 、W 2max , D, T and P satisfy equations (1) and (3), or the relationship satisfies equations (2) and (4).

[0078] According to some embodiments of the present invention, the slot is in a straight line shape.

[0079] According to some embodiments of the present invention, the maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max .

[0080] The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max .

[0081] The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max .

[0082] The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max .

[0083] Formulas (5) to (8) are:

[0084]

[0085]

[0086] When the diffusion region includes a first diffusion region and a second diffusion region, y1, L 1max 、L 2max 、W 1max 、W 2max , D, T and P simultaneously satisfy the relationships of equations (5) to (8).

[0087] In formulas (5) to (8), 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, and 0.02≤k4≤1.37.

[0088] According to some embodiments of the present invention, the maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max .

[0089] The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max .

[0090] The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max .

[0091] The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max .

[0092] When the diffusion region is only the first diffusion region or the second diffusion region, y1, L 1max 、L 2max 、W 1max 、W 2max , D, T, and P satisfy equations (5) and (7), or satisfy equations (6) and (8).

[0093] According to some embodiments of the present invention, a cross-sectional area of ​​the first diffusion region perpendicular to the axis of the rotor core is S1.

[0094] According to some embodiments of the present invention, a cross-sectional area of ​​the second diffusion region perpendicular to the axis of the rotor core is S2.

[0095] Formula (9) and formula (10) are:

[0096]

[0097] When the diffusion region is the first diffusion region and the second diffusion region, y1, S1, S2, D, T and P simultaneously satisfy the relationship of formula (9) and formula (10).

[0098] In formula (9) and formula (10), 0.01≤k1≤1.2, 0.01≤k2≤1.2.

[0099] When the diffusion region is only the first diffusion region or the second diffusion region, y1, S1, S2, D, T and P satisfy the relationship of formula (9) or formula (10).

[0100] According to some embodiments of the present invention, the diffusion regions of the permanent magnet in cross sections with different widths and thicknesses may have the same area.

[0101] According to some embodiments of the present invention, the diffusion zone areas of the permanent magnet in cross sections with different widths and thicknesses may also be different.

[0102] According to some embodiments of the present invention, the heavy rare earth element may be uniformly distributed in the diffusion zone.

[0103] According to some embodiments of the present invention, the heavy rare earth element may also be distributed non-uniformly in the diffusion zone.

[0104] According to some embodiments of the present invention, the permanent magnet comprises a radially magnetized permanent magnet.

[0105] According to some embodiments of the present invention, the permanent magnet further comprises a parallel magnetized permanent magnet.

[0106] According to some embodiments of the present invention, the heavy rare earth element includes dysprosium, terbium or a combination thereof.

[0107] According to some embodiments of the present invention, the number of pole pairs P of the permanent magnet is ≥2.

[0108] According to some embodiments of the present invention, the rotor core is formed by stacking a plurality of silicon steel sheets.

[0109] A second aspect of the present invention provides a permanent magnet motor comprising the above-mentioned rotor structure.

[0110] The main components of a permanent magnet motor include a stator structure and a rotor structure, wherein the stator structure and the rotor structure are coaxially arranged, and the rotor structure can rotate relative to the stator structure.

[0111] The stator core, when winding wire around the stator teeth and setting up stator windings within the winding slots, provides a normal magnetic field driving the rotor structure, thereby enabling the rotor structure to rotate. Specifically, the rotor structure is coaxial with the stator structure and primarily consists of two components: the rotor core and permanent magnets. When the stator structure is energized to generate a vector magnetic field, the magnetic components rotate under the magnetic force, thereby enabling the rotor structure to move.

[0112] It should be noted that the axis of the stator core is collinear with the axis of the rotor core, and the stator teeth and permanent magnets are arranged around the axis, and are generally evenly arranged.

[0113] One of the technical solutions of the present invention regarding the permanent magnet motor has at least the following beneficial effects:

[0114] The permanent magnet motor of the present invention includes the rotor structure of the present invention, and thus the permanent magnet motor of the present invention has all the effects of the rotor structure. Specifically:

[0115] The rotor structure includes a rotor core and a plurality of permanent magnets. Among them, a plurality of sets of slots are circumferentially formed on the end surface of the rotor core, and each permanent magnet is correspondingly embedded in each slot. The permanent magnet contains heavy rare earth elements. The permanent magnet can be divided into a diffusion region and a non-diffusion region according to the content of the heavy rare earth elements. In the diffusion region, the heavy rare earth elements account for g% by mass. In the non-diffusion region, the heavy rare earth elements account for g'% by mass. The relationship between g' and g is: g' < g. A first magnetic isolation bridge with a thickness of y1 is provided between the permanent magnets. The maximum length of the diffusion region in the width direction of the permanent magnet is L max The maximum length of the diffusion region in the thickness direction of the permanent magnet is W max The outer diameter of the rotor core is D. The stack thickness of the rotor core is T. The number of pole pairs of the permanent magnet is P. Among these parameters, when y1, L max 、W max 、D, T, and P simultaneously satisfy the relational expressions of formula (A) and formula (B), it is possible to improve the local demagnetization resistance ability of the permanent magnet on the premise of ensuring demagnetization reliability and not increasing the volume of the permanent magnet, thereby improving the demagnetization resistance ability of the rotor, reducing the rotor cost, and the motor performance can meet the application requirements on the whole machine.

[0116] The third aspect of the present invention provides a compressor including the rotor structure described above.

[0117] One technical solution in the technical solution of the compressor of the present invention has at least the following beneficial effects:

[0118] The compressor of the present invention includes the rotor structure of the present invention. Therefore, the compressor of the present invention also has all the effects of this rotor structure. Specifically:

[0119] The rotor structure includes a rotor core and a plurality of permanent magnets. Among them, a plurality of sets of slots are circumferentially formed on the end surface of the rotor core, and each permanent magnet is correspondingly embedded in each slot. The permanent magnet contains heavy rare earth elements. The permanent magnet can be divided into a diffusion region and a non-diffusion region according to the content of the heavy rare earth elements. In the diffusion region, the heavy rare earth elements account for g% by mass. In the non-diffusion region, the heavy rare earth elements account for g'% by mass. The relationship between g' and g is: g' < g. A first magnetic isolation bridge with a thickness of y1 is provided between the permanent magnets. The maximum length of the diffusion region in the width direction of the permanent magnet is L max The maximum length of the diffusion region in the thickness direction of the permanent magnet is W max The outer diameter of the rotor core is D. The stack thickness of the rotor core is T. The number of pole pairs of the permanent magnet is P. Among these parameters, when y1, L max 、W maxWhen D, T, and P simultaneously satisfy the relational expressions of formula (A) and formula (B), the ability of the permanent magnet to resist local demagnetization can be improved on the premise of ensuring demagnetization reliability and not increasing the volume of the permanent magnet, thereby improving the demagnetization resistance ability of the rotor, reducing the rotor cost, and the motor performance can meet the application requirements of the whole machine. Thus, the performance of the final compressor is improved.

[0120] The fourth aspect of the present invention provides a refrigeration device, including the permanent magnet motor or the compressor described above.

[0121] One technical solution in the technical solution of the present invention regarding the refrigeration device has at least the following beneficial effects:

[0122] The refrigeration device of the present invention includes the rotor structure of the present invention. Thus, the compressor of the present invention also has all the effects of this rotor structure. Specifically:

[0123] The rotor structure includes a rotor core and a plurality of permanent magnets. Among them, a plurality of groups of slots are circumferentially formed on the end surface of the rotor core, and each permanent magnet is correspondingly embedded in each slot. The permanent magnet contains heavy rare earth elements. The permanent magnet can be divided into a diffusion region and a non-diffusion region according to the content of the heavy rare earth elements. In the diffusion region, the heavy rare earth elements contain g% by mass percentage. In the non-diffusion region, the heavy rare earth elements contain g'% by mass percentage. The relationship between g' and g is: g' < g. A first magnetic isolation bridge with a thickness of y1 is provided between the permanent magnets. The maximum length of the diffusion region along the width direction of the permanent magnet is L max The maximum length of the diffusion region along the thickness direction of the permanent magnet is W max The outer diameter of the rotor core is D. The product thickness of the rotor core is T. The number of pole pairs of the permanent magnet is P. Among these parameters, when y1, L max 、W max 、D, T, and P simultaneously satisfy the relational expressions of formula (A) and formula (B), the ability of the permanent magnet to resist local demagnetization can be improved on the premise of ensuring demagnetization reliability and not increasing the volume of the permanent magnet, thereby improving the demagnetization resistance ability of the rotor, reducing the rotor cost, and the motor performance can meet the application requirements of the whole machine. Thus, the performance of the final refrigeration device is improved.

[0124] According to some embodiments of the present invention, the refrigeration device includes an air conditioner.

[0125] According to some embodiments of the present invention, the air conditioner is a household air conditioner. BRIEF DESCRIPTION OF THE DRAWINGS

[0126] Figure 1 It is one of the schematic diagrams of the rotor structure when the slot is V-shaped.

[0127] Figure 2 This is the second schematic diagram of the rotor structure when the slot is V-shaped.

[0128] Figure 3 It is a schematic diagram of the width and thickness directions of the permanent magnet.

[0129] Figure 4 Schematic diagram of a permanent magnet with only one diffusion region.

[0130] Figure 5 This is a schematic diagram of a permanent magnet with a U-shaped diffusion region.

[0131] Figure 6 This is a schematic diagram of a permanent magnet with a quadrilateral diffusion region.

[0132] Figure 7 This is a schematic diagram of a permanent magnet with a three-strip diffusion region.

[0133] Figure 8 This is a schematic diagram when the diffusion zones are distributed at both ends of the permanent magnet in the width direction.

[0134] Figure 9 This is one of the schematic diagrams of the rotor structure when the slots are in a straight line.

[0135] Figure 10 This is the second schematic diagram of the rotor structure when the slots are in a straight line.

[0136] Figure 11 This is a partially enlarged schematic diagram of the diffusion zone when the slot is V-shaped.

[0137] Figure 12 This is a partially enlarged schematic diagram of the diffusion zone when the slot is in a straight line shape.

[0138] Figure 13 This is a schematic diagram of the permanent magnet motor structure when the slot is V-shaped.

[0139] Figure 14 This is a schematic diagram of the permanent magnet motor structure when the slots are in a straight line.

[0140] Reference numerals:

[0141] 100: rotor core;

[0142] 110: slot;

[0143] 120: Permanent magnet;

[0144] 130: diffusion zone;

[0145] 1310: first diffusion zone;

[0146] 1320: Second diffusion zone;

[0147] 1330: third diffusion zone;

[0148] 140: first magnetic isolation bridge;

[0149] 150: second magnetic isolation bridge;

[0150] 200: stator. DETAILED DESCRIPTION

[0151] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0152] In the description of the present invention, if there are descriptions of first, second, third, etc., they are only used to distinguish technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0153] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0154] In the description of the present invention, it should be noted that, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0155] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0156] refer to Figure 1 and Figure 2 As shown, in some embodiments of the present invention, the present invention provides a rotor structure, including a rotor core 100 and a plurality of permanent magnets 120. Specifically:

[0157] The rotor core 100 has multiple slots 110 circumferentially formed on its end surface. Each permanent magnet 120 is embedded in a corresponding slot 110. The permanent magnets 120 contain heavy rare earth elements and can be divided into a diffusion region 130 and a non-diffusion region based on the content of heavy rare earth elements.

[0158] The diffusion region 130 contains heavy rare earth elements with a mass percentage of g%, while the non-diffusion region contains heavy rare earth elements with a mass percentage of g`, where g`<g.

[0159] A first magnetic isolation bridge 140 is provided between the permanent magnets 120.

[0160] The thickness of the first magnetic isolation bridge 140 is y1, and the maximum length of the diffusion region 130 along the width direction of the permanent magnet 120 is L max The maximum length of the diffusion region 130 along the thickness direction of the permanent magnet 120 is W max The outer diameter of the rotor core 100 is D, the stack thickness of the rotor core 100 is T, and the number of pole pairs of the permanent magnet 120 is P. Among the above parameters, y1, L max W max D, T, and P simultaneously satisfy the relational expressions of formula (A) and formula (B):

[0161]

[0162] In formula (A) and formula (B), 0.01≤k A ≤2.00, 0.01≤k B ≤2.00.

[0163] It can be understood that the rotor structure of the present invention includes a rotor core and multiple permanent magnets.

[0164] Among them, multiple groups of slots are circumferentially provided on the end face of the rotor core, and each permanent magnet is correspondingly embedded in each slot. The permanent magnet contains heavy rare earth elements. According to the content of the heavy rare earth elements, the permanent magnet can be divided into a diffusion region and a non-diffusion region. In the diffusion region, it contains heavy rare earth elements with a mass percentage of g%. In the non-diffusion region, it contains heavy rare earth elements with a mass percentage of g`. The relationship between g` and g is: g`<g. A first magnetic isolation bridge is provided between the permanent magnets, with a thickness of y1. The maximum length of the diffusion region along the width direction of the permanent magnet is L max The maximum length of the diffusion region along the thickness direction of the permanent magnet is W max The outer diameter of the rotor core is D. The stack thickness of the rotor core is T. The number of pole pairs of the permanent magnet is P. Among these parameters, y1, L max W max When D, T, and P simultaneously satisfy the relational expressions of formula (A) and formula (B), it is possible to improve the local demagnetization resistance ability of the permanent magnet on the premise of ensuring demagnetization reliability and not increasing the volume of the permanent magnet, thereby improving the demagnetization resistance ability of the rotor, reducing the rotor cost, and the performance of the motor can meet the application requirements on the whole machine. Thus, the performance of the final refrigeration equipment is improved.

[0165] It can also be understood that the rotor structure of the present invention makes the key parameters y1, L max Wmax , D, T and P are combined with the coating position of the heavy rare earth coating to form a formula. If the overall anti-demagnetization ability of the motor structure design is poor, in order to ensure reliability, the coating position (length, width, area) is required to be larger; on the contrary, if the overall anti-demagnetization ability of the motor structure design is good, the coating position (length, width, area) can be designed to be relatively small.

[0166] It should be noted that the magnetic isolation bridge can play a magnetic isolation role to a certain extent. By setting up the magnetic isolation bridge, the possibility of magnetic circuit disorder and leakage problems inside the rotor structure can be effectively reduced. Specifically, the smaller the width of the magnetic isolation bridge, the greater the reverse magnetic field on both sides of the permanent magnet (under the same conditions, it is easier to demagnetize). Furthermore, the magnetic isolation bridge mainly affects the size of the motor's leakage magnetic coefficient. The larger the leakage magnetic coefficient, the weaker the permanent magnet is affected by the reverse magnetic field, and the better the demagnetization resistance.

[0167] It should also be noted that the thickness of the magnetic isolation bridge refers to the distance between the edge of the permanent magnet placement slot, close to the outer diameter of the rotor core, and the side of the outer diameter of the rotor core. Figure 2 、 Figure 10 、 Figure 11 and Figure 12 It can help with understanding.

[0168] It should also be noted that the diffusion zone refers to a layer of heavy rare earth coating applied to the surface of the permanent magnet substrate during the permanent magnet manufacturing process. Different formulations can be formulated to meet specific requirements. For higher demagnetization resistance requirements, the heavy rare earth content in the formulation should be higher. Applying two different concentrations of heavy rare earth formulations to the permanent magnet substrate creates diffusion zones with varying demagnetization resistance. After the heavy rare earth coating is applied, it undergoes a high-temperature treatment to allow the heavy rare earth elements to diffuse into the permanent magnet, forming a stable grain boundary state.

[0169] It should be noted that, in order to adapt to the application environment of household air conditioners, the permanent magnets of variable frequency motors are mostly NdFeB permanent magnets containing heavy rare earth elements and high coercivity. 14 B-based permanent magnet materials are primarily composed of neodymium, iron, and boron. To achieve different performance characteristics, heavy rare earth metals such as dysprosium and terbium can be used to replace some of the neodymium in permanent magnets. Heavy rare earth metals refer to those with atomic numbers ranging from 64 to 71, plus element 39: gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium.

[0170] It should also be noted that y1, L max 、W max The units of , D and T are all millimeters.

[0171] The thickness of the magnetic isolation bridge may range from 0.4 mm to 0.9 mm.

[0172] The maximum length L of the diffusion zone along the width of the permanent magnet max The range can be 1mm to 15mm.

[0173] The maximum length W of the diffusion zone along the thickness direction of the permanent magnet max The range can be 1mm to 3.5mm.

[0174] The outer diameter D of the rotor core may be in the range of 60 mm to 90 mm.

[0175] The thickness T of the rotor core may be in the range of 50 mm to 120 mm.

[0176] The number of permanent magnet pole pairs P may range from 2 to 5.

[0177] In some embodiments of the present invention, the shape of the permanent magnet includes a cuboid, which is divided into a length direction, a width direction, and a thickness direction for ease of description and understanding.

[0178] In some embodiments of the present invention, the diffusion regions are distributed along the width direction of the permanent magnet to form a plurality of diffusion regions.

[0179] In some embodiments of the present invention, the diffusion regions are distributed along the width of the permanent magnet to form a plurality of diffusion regions. The distribution shapes of these diffusion regions include a U-shaped structure, a quadrangular structure, and a three-strip structure. Detailed description will be given below with reference to the accompanying drawings.

[0180] refer to Figure 3 It can be better understood that the width direction and thickness direction of the permanent magnet referred to in the present invention are reversed.

[0181] In some embodiments of the present invention, the diffusion regions may be distributed along the width direction of the permanent magnet to form one, two or more diffusion regions.

[0182] In some embodiments of the present invention, the diffusion zone can be distributed along the width direction of the permanent magnet, with only one diffusion zone. Figure 4 As shown in the figure, the advantage of having only one diffusion zone is that it uses less heavy rare earth elements and is cost-effective. However, its disadvantages are that rotor production is complex, requiring orientation confirmation, and the diffusion zone needs to be close to the stator winding side, making it the most susceptible to demagnetization. The case of having only one diffusion zone is suitable for highly automated applications, eliminating the need for manual identification and positioning.

[0183] In some embodiments of the present invention, the diffusion regions are distributed along the width direction of the permanent magnet. The first diffusion region 1310, the second diffusion region 1320 and the third diffusion region 1330 may form a U-shaped structure. Figure 5 The advantage of the U-shaped structure is that it covers the entire area prone to demagnetization of the permanent magnet, resulting in excellent demagnetization resistance. However, its disadvantage is the high cost due to the high use of heavy rare earth elements. The U-shaped structure is suitable for applications requiring high demagnetization resistance.

[0184] In some embodiments of the present invention, the diffusion regions are distributed along the width direction of the permanent magnet, and the first diffusion region 1310 and the second diffusion region 1320 can also form a quadrangular structure. Figure 6 The advantage of the quadrangular structure is that it uses less heavy rare earth elements and is low cost. Its disadvantage is that some areas susceptible to demagnetization are not fully included. The quadrangular structure is suitable for applications with small permanent magnet heights, that is, when the rotor thickness is small.

[0185] In some embodiments of the present invention, the diffusion regions are distributed along the width direction of the permanent magnet. The first diffusion region 1310, the second diffusion region 1320 and the third diffusion region 1330 can also form a three-strip structure. Figure 7 The advantage of the three-stripe structure is that different diffusion zones can correspond to different demagnetization resistance characteristics, allowing for targeted design. The disadvantage is the complex manufacturing process for the permanent magnets. The three-stripe structure is suitable for special rotor structures and can specifically improve demagnetization resistance.

[0186] refer to Figure 1 and Figure 2 As shown, in some embodiments of the present invention, the diffusion region includes a first diffusion region 1310 and a second diffusion region 1320, the first diffusion region 1310 contains heavy rare earth elements with a mass percentage of g1%, and the second diffusion region 1320 contains heavy rare earth elements with a mass percentage of g2%.

[0187] In some embodiments of the present invention, the mass percentage of the heavy rare earth element in the non-diffusion region is 0-0.6%.

[0188] In some embodiments of the present invention, the mass percentage of the heavy rare earth element in the non-diffusion region is 0-0.55%.

[0189] In some embodiments of the present invention, the mass percentage of heavy rare earth elements in the non-diffusion region is 0-0.53%.

[0190] In some embodiments of the present invention, the mass percentage g1% of the heavy rare earth element in the first diffusion region 1310 is 1.0% to 2.0%.

[0191] In some embodiments of the present invention, the mass percentage g1% of the heavy rare earth element in the first diffusion region 1310 is 1.05% to 2.00%.

[0192] In some embodiments of the present invention, the mass percentage g2% of the heavy rare earth element in the second diffusion region 1320 is 0.5% to 1.4%.

[0193] In some embodiments of the present invention, the mass percentage g2% of the heavy rare earth element in the second diffusion region 1320 is 0.59% to 1.25%.

[0194] In some embodiments of the present invention, the slot is V-shaped.

[0195] In some embodiments of the present invention, the V-shaped opening faces the stator of the motor.

[0196] It's understandable that because heavy rare earth magnets have lower intrinsic coercivity than conventional rare earth magnets, their direct use can reduce the motor's demagnetization resistance. However, the V-shaped slots enhance the motor's demagnetization resistance. The V-shaped slots also achieve a magnetic field concentration effect, increasing the main magnetic flux and, in turn, the back EMF, ultimately boosting motor efficiency.

[0197] The reverse magnetic field strength applied when the sum of the microscopic magnetic dipole moment vector inside the magnet is reduced to 0 is called the intrinsic coercive force (H cj ).

[0198] Intrinsic coercivity is different from coercivity (H cb ). When the reverse magnetic field H=H cb When the external magnetic induction intensity is zero, the residual magnetization intensity (B r ) is not zero, but the reverse magnetic field applied is different from B r effects cancel each other out.

[0199] When the reverse magnetic field H=H cj When the residual magnetization of the magnet drops to 0.

[0200] The magnitude of the intrinsic coercive force is closely related to the temperature stability of the rare earth permanent magnet. The higher the intrinsic coercive force, the better the temperature stability.

[0201] refer to Figure 1 and Figure 2 As shown, in some embodiments of the present invention, a second magnetic isolation bridge 150 is further provided between each permanent magnet, and the second magnetic isolation bridge 150 is provided at the bottom of the V-shape.

[0202] In some embodiments of the present invention, y2 is the thickness of the second magnetic isolation bridge 150, L 1max is the maximum length of the first diffusion region 1310 along the width direction of the permanent magnet, W 1max is the maximum length of the first diffusion region 1310 along the thickness direction of the permanent magnet, L 2max is the maximum length of the second diffusion region 1320 along the width direction of the permanent magnet, W 2max is the maximum length of the second diffusion region 1320 along the thickness direction of the permanent magnet. When the diffusion regions are the first diffusion region 1310 and the second diffusion region 1320, y1, y2, and L 1max 、L 2max 、W 1max 、W2max , D, T and P simultaneously satisfy the relationship between formula (1) to formula (4):

[0203]

[0204]

[0205] In formulas (1) to (4), 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, and 0.02≤k4≤1.37.

[0206] L 1max 、L 2max 、W 1max 、W 2max It is the coating position defined in the present invention.

[0207] It should be noted that when the thickness of the magnetic isolation bridge is uneven, y1 and y2 take the minimum value.

[0208] A specific embodiment will be described below to better understand the technical solution of the present invention.

[0209] This embodiment provides a rotor structure, in which the relevant parameters are as follows:

[0210] D: 88mm; T: 90mm; P: 3; y1: 0.5mm; y2: 0.8mm;

[0211] L 1max =L 2max =4mm; W 1max =W 2max =2.50mm.

[0212] K1=k2=0.1752, k3=k4=0.219.

[0213] The permanent magnet has a length of 89 mm, a width of 18 mm, a thickness of 2.5 mm, and a brand of 52SH.

[0214] The diffusion zone is distributed at both ends of the permanent magnet in the width direction. Figure 8 shown.

[0215] The diffusion zone has a length of 89 mm, a width of 4 mm, and a thickness of 2.5 mm.

[0216] The intrinsic coercive force of the non-diffusion region of the permanent magnet is 1920KA / m.

[0217] The intrinsic coercive force of the permanent magnet diffusion region is ≥2070KA / m.

[0218] The demagnetization rate of the permanent magnet at 130°C / 35A is 3.89%.

[0219] The demagnetization rate of the permanent magnet at 130°C / 43A is 6.73%.

[0220] For permanent magnets of the same size and without diffusion zone, the demagnetization rate is 6.5% at 130℃ / 35A and 8.63% at 130℃ / 43A.

[0221] In some embodiments of the present invention, the thickness of the second magnetic isolation bridge 150 is y2, and the maximum length of the first diffusion region 1310 along the width direction of the permanent magnet is L. 1max The maximum length of the first diffusion region 1310 along the thickness direction of the permanent magnet is W 1max The maximum length of the second diffusion region 1320 along the width direction of the permanent magnet is L 2max The maximum length of the second diffusion region 1320 along the thickness direction of the permanent magnet is W 2max When the diffusion region is the first diffusion region 1310 or the second diffusion region 1320, y1, y2, L 1max 、L 2max 、W 1max 、W 2max , D, T and P satisfy equations (1) and (3), or the relationship satisfies equations (2) and (4):

[0222]

[0223]

[0224] In formulas (1) to (4), 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, and 0.02≤k4≤1.37.

[0225] It should be noted that when the thickness of the magnetic isolation bridge is uneven, y1 and y2 take the minimum value.

[0226] refer to Figure 9 and Figure 10 As shown, in some embodiments of the present invention, the slot is in a straight line shape.

[0227] In some embodiments of the present invention, the maximum length of the first diffusion region 1310 along the width direction of the permanent magnet 120 is L 1max The maximum length of the first diffusion region 1310 along the thickness direction of the permanent magnet 120 is W 1max The maximum length of the second diffusion region 1320 along the width direction of the permanent magnet 120 is L 2max The maximum length of the second diffusion region 1320 along the thickness direction of the permanent magnet 120 is W 2max When the diffusion regions are the first diffusion region 1310 and the second diffusion region 1320, y1, L 1max 、L2max 、W 1max 、W 2max , D, T and P simultaneously satisfy the relationship between formula (5) to formula (8):

[0228]

[0229]

[0230] Among them, 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, and 0.02≤k4≤1.37.

[0231] In some embodiments of the present invention, the maximum length of the first diffusion region 1310 along the width direction of the permanent magnet 120 is L 1max The maximum length of the first diffusion region 1310 along the thickness direction of the permanent magnet 120 is W 1max The maximum length of the second diffusion region 1320 along the width direction of the permanent magnet 120 is L 2max The maximum length of the second diffusion region 1320 along the thickness direction of the permanent magnet 120 is W 2max When the diffusion region is the first diffusion region 1310 or the second diffusion region 1320, y1, L 1max 、L 2max 、W 1max 、W 2max , D, T and P satisfy equations (5) and (7), or the relationship satisfies equations (6) and (8):

[0232]

[0233]

[0234] In formulas (5) to (8), 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, and 0.02≤k4≤1.37.

[0235] refer to Figure 11 and Figure 12 As shown, in some embodiments of the present invention, the cross-sectional area of ​​the first diffusion region perpendicular to the axis of the rotor core is S1, and the cross-sectional area of ​​the second diffusion region perpendicular to the axis of the rotor core is S2. When the diffusion regions are the first diffusion region and the second diffusion region, y1, S1, S2, D, T, and P simultaneously satisfy the relationship between equations (9) and (10):

[0236]

[0237] Among them, 0.01≤k1≤1.2, 0.01≤k2≤1.2.

[0238] A specific embodiment will be described below to better understand the technical solution of the present invention.

[0239] This embodiment provides a rotor structure, in which the relevant parameters are as follows:

[0240] D: 88mm; T: 90mm; P: 3; y1: 0.5mm;

[0241] S1=S2=10.0mm 2 .

[0242] K1=k2=0.1599.

[0243] The permanent magnet has a length of 89 mm, a width of 18 mm, a thickness of 2.5 mm, and a brand of 52SH.

[0244] The diffusion zone is distributed at both ends of the permanent magnet in the width direction. Figure 8 shown.

[0245] The diffusion zone has a length of 89 mm, a width of 4 mm, and a thickness of 2.5 mm.

[0246] The intrinsic coercive force of the non-diffusion region of the permanent magnet is 1920KA / m.

[0247] The intrinsic coercive force of the permanent magnet diffusion region is ≥2070KA / m.

[0248] The demagnetization rate of the permanent magnet at 130°C / 35A is 4.1%.

[0249] The demagnetization rate of the permanent magnet at 130°C / 43A is 6.94%.

[0250] For permanent magnets of the same size and without diffusion zone, the demagnetization rate is 6.5% at 130℃ / 35A and 8.63% at 130℃ / 43A.

[0251] It should be noted that the demagnetization rate test method is mainly:

[0252] First, place the magnetized saturated rotor at room temperature and measure the rotor magnetic flux.

[0253] Then, the rotor after the initial magnetic flux test is placed in a constant temperature box for more than 4 hours, and the constant temperature box is set to the specified temperature (130℃);

[0254] Then connect the test DC motor to the DC power supply and set the demagnetization current according to the pre-set demagnetization current value (43A, 50A, etc.);

[0255] When ready, remove the rotor from the constant temperature box, install the demagnetization test fixture, and rotate the rotor one circle under the DC demagnetization current;

[0256] After completion, place the rotor at room temperature for more than 4 hours, and then measure the rotor temperature and magnetic flux after demagnetization

[0257] Data collation, calculation of demagnetization rate, the calculation formula is as follows ( Need to be converted to Same temperature):

[0258]

[0259] The rotor flux at the beginning of the demagnetization test.

[0260] The magnetic flux of the rotor after the demagnetization test at the i-th demagnetization current value.

[0261] In some embodiments of the present invention, the cross-sectional area of ​​the first diffusion region perpendicular to the axis of the rotor core is S1, and the cross-sectional area of ​​the second diffusion region perpendicular to the axis of the rotor core is S2. When the diffusion region is the first diffusion region or the second diffusion region, y1, S1, S2, D, T, and P satisfy the relationship of formula (9) or formula (10):

[0262]

[0263] Among them, 0.01≤k1≤1.2, 0.01≤k2≤1.2.

[0264] In some embodiments of the present invention, the diffusion regions of the permanent magnet have the same area in cross sections with different widths and thicknesses.

[0265] In some embodiments of the present invention, the diffusion regions of the permanent magnet have different areas in cross sections with different widths and thicknesses.

[0266] In some embodiments of the present invention, the heavy rare earth elements are uniformly distributed in the diffusion zone.

[0267] In some embodiments of the present invention, the heavy rare earth elements are non-uniformly distributed in the diffusion region.

[0268] In some embodiments of the present invention, the permanent magnet comprises a radially magnetized permanent magnet.

[0269] In some embodiments of the present invention, the permanent magnets include parallel-magnetized permanent magnets.

[0270] It can be understood that radial magnetization is magnetization in the diameter direction. If the two magnets are adsorbed on the side, it is radial magnetization.

[0271] In some embodiments of the present invention, the heavy rare earth element includes dysprosium, terbium, or a combination thereof.

[0272] Dysprosium is a silvery-white metal with the symbol Dy. It is soft and can be cut with a knife. Its melting point is 1412°C, boiling point is 2562°C, and density is 8.55g / cm 3 Dysprosium exhibits superconductivity near absolute zero. Dysprosium is quite stable in air but readily oxidized by air and water at high temperatures, forming dysprosium oxide. Dysprosium is primarily used in the manufacture of new lighting sources, such as dysprosium lamps. Dysprosium can also be used as a control material in reactors, and dysprosium compounds can be used as catalysts in the oil refining industry.

[0273] Terbium is a member of the lanthanide series, with an atomic number of 65 and an element symbol of Tb. Its elemental form is a silvery-white metal.

[0274] In some embodiments of the present invention, the number of permanent magnet pole pairs P is ≥2.

[0275] According to some embodiments of the present invention, the rotor core is formed by laminating a plurality of silicon steel sheets.

[0276] In some other embodiments of the present invention, the present invention further provides a permanent magnet motor including a rotor structure.

[0277] It is understood that the main components of a permanent magnet motor include a stator structure and a rotor structure, wherein the stator structure and the rotor structure are coaxially arranged, and the rotor structure can rotate relative to the stator structure.

[0278] The stator core, when winding wire around the stator teeth and setting up stator windings within the winding slots, provides a normal magnetic field driving the rotor structure, thereby enabling the rotor structure to rotate. Specifically, the rotor structure is coaxial with the stator structure and primarily consists of two components: the rotor core and permanent magnets. When the stator structure is energized to generate a vector magnetic field, the magnetic components rotate under the magnetic force, thereby enabling the rotor structure to move.

[0279] It should be noted that the axis of the stator core is collinear with the axis of the rotor core, and the stator teeth and permanent magnets are arranged around the axis, and are generally evenly arranged.

[0280] It can be understood that the permanent magnet motor of the present invention includes the rotor structure of the present invention, and thus the permanent magnet motor of the present invention has all the effects of the rotor structure. Specifically, the rotor structure includes a rotor core and a plurality of permanent magnets.

[0281] Among them, multiple groups of slots are provided on the end surface of the rotor core along the circumferential direction, and each permanent magnet is correspondingly embedded in each slot.

[0282] Permanent magnets contain heavy rare earth elements. Permanent magnets can be divided into diffusion zone and non-diffusion zone according to the content of heavy rare earth elements.

[0283] The diffusion zone contains heavy rare earth elements with a mass percentage of g%, and the non-diffusion zone contains heavy rare earth elements with a mass percentage of g'%.

[0284] The relationship between g` and g is g` <g。

[0285] A first magnetic isolation bridge is provided between the permanent magnets; the thickness of the first magnetic isolation bridge is y1.

[0286] The maximum length of the diffusion zone along the width of the permanent magnet is L max .

[0287] The maximum length of the diffusion zone along the thickness direction of the permanent magnet is W max .

[0288] The outer diameter of the rotor core is D.

[0289] The thickness of the rotor core is T.

[0290] The number of permanent magnet pole pairs is P.

[0291] Among the above parameters, y1, L max 、W max When , D, T and P satisfy the relationship of formula (A) and formula (B) at the same time, the local anti-demagnetization ability of the permanent magnet can be improved without increasing the volume of the permanent magnet while ensuring the demagnetization reliability, thereby improving the anti-demagnetization ability of the rotor and reducing the rotor cost. The motor performance can meet the application requirements of the whole machine.

[0292] In some other embodiments of the present invention, the present invention further provides a compressor including a rotor structure. Figure 13 and Figure 14 As shown, the compressor includes a rotor structure and a stator 200 wound around the rotor structure.

[0293] It can be understood that the compressor of the present invention includes the rotor structure of the present invention, and thus the compressor of the present invention also has all the effects of the rotor structure.

[0294] Specifically, the rotor structure includes a rotor core and a plurality of permanent magnets.

[0295] A plurality of slots are provided on the end surface of the rotor core along the circumferential direction, and each permanent magnet is correspondingly embedded in each slot.

[0296] Permanent magnets contain some heavy rare earth elements. Permanent magnets can be divided into diffusion zone and non-diffusion zone according to the content of heavy rare earth elements.

[0297] The diffusion zone contains heavy rare earth elements with a mass percentage of g%.

[0298] The non-diffusion zone contains heavy rare earth elements with a mass percentage of g`%.

[0299] The relationship between g` and g is g` <g。

[0300] A first magnetic isolation bridge is provided between the permanent magnets, and has a thickness of y1.

[0301] The maximum length of the diffusion zone along the width of the permanent magnet is L max .

[0302] The maximum length of the diffusion zone along the thickness direction of the permanent magnet is W max .

[0303] The outer diameter of the rotor core is D.

[0304] The thickness of the rotor core is T.

[0305] The number of permanent magnet pole pairs is P.

[0306] Among the above parameters, y1, L max 、W max When , D, T, and P simultaneously satisfy the relationships of equations (A) and (B), the permanent magnet's local demagnetization resistance can be improved while ensuring demagnetization reliability and without increasing the size of the permanent magnet. This, in turn, improves the rotor's demagnetization resistance, reduces rotor costs, and ensures that motor performance meets the application requirements of the entire machine. Ultimately, compressor performance is improved.

[0307] In some other embodiments of the present invention, the present invention further provides a refrigeration device including a permanent magnet motor or a compressor.

[0308] It can be understood that the refrigeration equipment of the present invention includes the rotor structure of the present invention, and thus the compressor of the present invention also has all the effects of the rotor structure.

[0309] Specifically, the rotor structure includes a rotor core and a plurality of permanent magnets.

[0310] A plurality of slots are provided on the end surface of the rotor core along the circumferential direction, and each permanent magnet is correspondingly embedded in each slot.

[0311] Permanent magnets contain some heavy rare earth elements. Permanent magnets can be divided into diffusion zone and non-diffusion zone according to the content of heavy rare earth elements.

[0312] The diffusion zone contains heavy rare earth elements with a mass percentage of g%.

[0313] The non-diffusion zone contains heavy rare earth elements with a mass percentage of g'%.

[0314] The relationship between g` and g is g` <g。

[0315] A first magnetic isolation bridge is provided between the permanent magnets, and has a thickness of y1.

[0316] The maximum length of the diffusion zone along the width of the permanent magnet is L max .

[0317] The maximum length of the diffusion zone along the thickness direction of the permanent magnet is W max .

[0318] The outer diameter of the rotor core is D.

[0319] The thickness of the rotor core is T.

[0320] The number of permanent magnet pole pairs is P.

[0321] Among the above parameters, y1, L max 、W max When , D, T, and P simultaneously satisfy the relationships of equations (A) and (B), the permanent magnet's local demagnetization resistance can be improved while ensuring demagnetization reliability and without increasing the size of the permanent magnet. This, in turn, improves the rotor's demagnetization resistance, reduces rotor costs, and ensures that motor performance meets the application requirements of the entire machine. Ultimately, the performance of the refrigeration equipment is improved.

[0322] In some embodiments of the present invention, refrigeration equipment includes but is not limited to refrigerators, freezers, air conditioners and other equipment with refrigeration functions.

[0323] The compressor is a core component of an air conditioner, compressing and driving the refrigerant in the air conditioner's refrigerant circuit. The air conditioner's compressor is typically installed in the outdoor unit. The compressor draws refrigerant from a low-pressure area, compresses it, and then sends it to a high-pressure area for cooling and condensation. Heat is dissipated into the air through the heat sink, and the refrigerant changes from a gas to a liquid, increasing its pressure.

[0324] The compressor's operating circuit is divided into an evaporation zone (low-pressure zone) and a condensation zone (high-pressure zone). The indoor and outdoor units of the air conditioner belong to either the low-pressure or high-pressure zone, depending on the operating conditions. The refrigerant then flows from the high-pressure zone to the low-pressure zone, where it is ejected through a capillary tube into the evaporator. The pressure drops dramatically, and the liquid refrigerant immediately turns to a vapor state. This vapor then absorbs a significant amount of heat from the air through the heat sink. As the air conditioner compressor continues to operate, it continuously absorbs heat from the low-pressure zone into the refrigerant, which is then transferred to the high-pressure zone for dissipation into the air, regulating the temperature.

[0325] In some embodiments of the present invention, the air conditioner is a household air conditioner.

[0326] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0327] Furthermore, 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 the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0328] In the present invention, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0329] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0330] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A rotor structure, characterized in that: Comprising: A rotor core, on the end face of which a plurality of groups of slots are circumferentially provided; A plurality of permanent magnets, each of which is correspondingly embedded in each of the slots. The permanent magnets contain heavy rare earth elements and are divided into a diffusion region and a non-diffusion region according to the content of the heavy rare earth elements. The diffusion region contains heavy rare earth elements with a mass percentage of g%, and the non-diffusion region contains heavy rare earth elements with a mass percentage of g`. g`<g. A first magnetic isolation bridge is provided between the permanent magnets; The thickness of the first magnetic isolation bridge is y1, and the maximum length of the diffusion region along the width direction of the permanent magnet is L max The maximum length of the diffusion zone along the thickness direction of the permanent magnet is W max The outer diameter of the rotor core is D, the thickness of the rotor core is T, and the number of pole pairs of the permanent magnet is P, wherein y1, L max 、W max , D, T and P satisfy the relationship between formula (A) and formula (B) at the same time: Where, 0.01≤k A ≤2.00、0.01≤k B ≤2.

00.

2. The rotor structure according to claim 1, characterized in that: The diffusion regions are distributed along the width direction of the permanent magnet and the number is several.

3. The rotor structure according to claim 2, characterized in that: The diffusion region includes a first diffusion region and / or a second diffusion region. The first diffusion region contains heavy rare earth elements with a mass percentage of g1%, and the second diffusion region contains heavy rare earth elements with a mass percentage of g2%.

4. The rotor structure according to claim 3, characterized in that: The mass percentage g1% of the heavy rare earth elements in the first diffusion region is 1.0% to 2.0%.

5. The rotor structure according to claim 3, characterized in that: The mass percentage g2% of the heavy rare earth elements in the second diffusion region is 0.5% to 1.4%.

6. The rotor structure according to claim 3, characterized in that: The slots are V-shaped.

7. The rotor structure according to claim 6, characterized in that: A second magnetic isolation bridge is further provided between each of the permanent magnets, and the second magnetic isolation bridge is provided at the bottom of the V shape.

8. The rotor structure according to claim 7, characterized in that: The thickness of the second magnetic isolation bridge is y2, and the maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max , when the diffusion region is the first diffusion region and the second diffusion region, y1, y2, L 1max 、L 2max 、W 1max 、W 2max , D, T and P simultaneously satisfy the relationship between formula (1) to formula (4): Where 0.02≤k1≤1.60, 0.02≤k2≤L60, 0.02≤k3≤1.37, 0.02≤k4≤1.

37.

9. The rotor structure according to claim 7, characterized in that: The thickness of the second magnetic isolation bridge is y2, and the maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max , when the diffusion region is the first diffusion region or the second diffusion region, y1, y2, L 1max 、L 2max 、W 1max 、W 2max , D, T and P satisfy the relationship between formula (1) and formula (3), or satisfy the relationship between formula (2) and formula (4): [[ID=I0]]Where 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, 0.02≤k4≤1.

37.

10. The rotor structure according to claim 3, characterized in that: The slots are linear.

11. The rotor structure according to claim 10, characterized in that: The maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max , when the diffusion region is the first diffusion region and the second diffusion region, y1, L 1max 、L 2max 、W 1max 、W 2max , D, T and P simultaneously satisfy the relationship between formula (5) to formula (8): Where 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, 0.02≤k4≤1.

37.

12. The rotor structure according to claim 10, characterized in that: The maximum length of the first diffusion region along the width direction of the permanent magnet is L 1max The maximum length of the first diffusion region along the thickness direction of the permanent magnet is W 1max The maximum length of the second diffusion region along the width direction of the permanent magnet is L 2max The maximum length of the second diffusion region along the thickness direction of the permanent magnet is W 2max When the diffusion region is the first diffusion region or the second diffusion region, y1, L 1max 、L 2max 、W 1max 、W 2max , D, T and P satisfy equations (5) and (7), or the relationship satisfies equations (6) and (8): Where 0.02≤k1≤1.60, 0.02≤k2≤1.60, 0.02≤k3≤1.37, 0.02≤k4≤1.

37.

13. The rotor structure according to claim 10, characterized in that: The cross-sectional area perpendicular to the axis of the rotor core of the first diffusion region is S1, and the cross-sectional area perpendicular to the axis of the rotor core of the second diffusion region is S2. When the diffusion region is the first diffusion region and the second diffusion region, the relationship formulas of y1, S1, S2, D, T and P simultaneously satisfy formula (9) and formula (10): Where 0.01≤k1≤1.2, 0.01≤k2≤1.

2.

14. The rotor structure according to claim 10, characterized in that The cross-sectional area perpendicular to the axis of the rotor core of the first diffusion region is S1, and the cross-sectional area perpendicular to the axis of the rotor core of the second diffusion region is S2. When the diffusion region is the first diffusion region or the second diffusion region, the relationship formulas of y1, S1, S2, D, T and P satisfy formula (9) or formula (10): Where 0.01≤k1≤1.2, 0.0 I≤k2≤1.

2.

15. The rotor structure according to any one of claims 1 to 14, characterized in that: The heavy rare earth elements include dysprosium element, terbium element or a combination thereof.

16. The rotor structure according to any one of claims 1 to 14, characterized in that: The number of pole pairs P of the permanent magnet is P≥2.

17. A permanent magnet motor, characterized in that: Comprising the rotor structure according to any one of claims 1 to 16.

18. A compressor, characterized in that: Comprising the rotor structure according to any one of claims 1 to 16.

19. A refrigeration device, characterized in that: Comprising the permanent magnet motor according to claim 17 or the compressor according to claim 18.

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