A motor rotor and its application

Abstract

The present invention discloses a motor rotor and its application, wherein the motor rotor comprises: an iron core provided with magnet slots, and permanent magnets arranged in a V shape in the magnet slots; the permanent magnets comprise at least one diffusion region and a non-diffusion region, wherein the content of heavy rare earth in the diffusion region is greater than that in the non-diffusion region; the permanent magnets are cut through a plane perpendicular to the axis of the iron core to obtain multiple cross sections; on at least one cross section, the area of ​​any diffusion region is S mm 2 A first magnetic isolation bridge with a thickness of y1 mm is provided at the tip of the V-shape, and a second magnetic isolation bridge with a thickness of y2 mm is provided at a position away from the tip of the V-shape. The number of pole pairs of the rotor is P. The relationship between the outer diameter and thickness of the core and the aforementioned parameters satisfies a corresponding mathematical relationship. The motor rotor provided by the present invention has a high cost advantage and anti-demagnetization performance. The present invention also provides applications of the motor rotor.

Description

Technical Field

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

[0002] The core component of temperature control equipment such as air conditioners is the compressor (or the motor in the compressor), specifically a variable frequency permanent magnet motor. The core component of a permanent magnet motor is the motor rotor containing permanent magnets. Therefore, the cost of permanent magnets affects the cost of temperature control equipment such as air conditioners to a certain extent. Compared with other types of permanent magnets, rare earth permanent magnets have better performance. Rare earth permanent magnets contain a certain amount of heavy rare earth elements such as praseodymium and neodymium. Although these permanent magnets have excellent anti-demagnetization properties, the reserves of heavy rare earth elements are limited and expensive. Furthermore, the prices of products such as rotors, motors, and compressors containing these traditional permanent magnets are also high.

[0003] The heavy rare earth content in rare earth permanent magnets is positively correlated with the demagnetization resistance of the permanent magnets, and even of motors containing such permanent magnets. Therefore, while conventional techniques can reduce the heavy rare earth content in permanent magnets to mitigate raw material sourcing and high costs, the resulting permanent magnets' demagnetization resistance is correspondingly weakened. This weakening trend becomes more pronounced as the power density of permanent magnet motors increases. Irreversible demagnetization of permanent magnets can negatively impact the performance and reliability of motors and compressors, severely reducing the product's service life.

[0004] In summary, how to balance the cost of motor components and the overall performance of the motor is imminent. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a motor rotor that can effectively improve the motor rotor's comprehensive performance, such as anti-demagnetization efficiency, while effectively suppressing a significant increase in cost.

[0006] The present invention also provides a permanent magnet motor comprising the motor rotor.

[0007] The present invention also provides a compressor comprising the above motor rotor or permanent magnet motor.

[0008] The present invention also provides a temperature regulating device comprising the compressor.

[0009] According to an embodiment of the first aspect of the present invention, a motor rotor is provided, comprising:

[0010] An iron core, wherein a magnet slot is provided on the iron core, and the outer diameter of the iron core is D mm and the thickness is T mm;

[0011] A permanent magnet, the permanent magnets being arranged in a V-shape and disposed in the magnet slot; the permanent magnets comprising at least one diffusion region and a non-diffusion region, the content of heavy rare earth in the diffusion region being greater than the content of heavy rare earth in the non-diffusion region;

[0012] Cutting the permanent magnet through a plane perpendicular to the axis of the core to obtain a plurality of cross sections;

[0013] On at least one cross section, the area of ​​any of the diffusion regions is S mm 2 ;

[0014] A magnetic isolation bridge, wherein the magnetic isolation bridge comprises a first magnetic isolation bridge with a thickness of y1 mm and a second magnetic isolation bridge with a thickness of y2 mm;

[0015] The first magnetic isolation bridge is provided at the tip of the V-shape, and the second magnetic isolation bridge is provided at a position of the V-shape away from the tip;

[0016] The number of pole pairs of the rotor is P;

[0017] and:

[0018]

[0019] Where 0.01≤k i ≤1.2.

[0020] The motor rotor according to the embodiment of the present invention has at least the following beneficial effects:

[0021] The fundamental reason for the price increase of permanent magnets and motors including permanent magnets is the price increase of heavy rare earth elements. The content of heavy rare earth elements will affect the remanence and coercive force of permanent magnets (positive correlation). The direct manifestation of coercive force is the anti-demagnetization ability. When the permanent magnets are of the same size and equipped with the same motor (motor rotor), permanent magnets with low coercive force have poor anti-demagnetization ability of the motor rotor, and the risk of rotor demagnetization is higher and the demagnetization is more obvious.

[0022] The thickness of the magnetic isolation bridge (y1 and y2) is related to the size of the motor's magnetic leakage coefficient, that is, the size of the reverse magnetic field directly opposite the permanent magnet. The larger the size of the magnetic isolation bridge, the better the anti-demagnetization ability, and the strength of the reverse magnetic field is relatively weaker.

[0023] The area of ​​the diffusion zone on a certain cross section affects the overall anti-demagnetization performance of the resulting motor rotor. If the overall anti-demagnetization capability of the motor rotor structure design is poor, S is required to be larger to ensure reliability. On the contrary, if the overall anti-demagnetization capability of the motor rotor structure design is good, S can be designed to be smaller.

[0024] The core's outer diameter (D) and thickness (T) are key dimensions of the motor rotor. Rotor sizes vary, as do the placement of the permanent magnets and related dimensions (such as the number and location of slits). The number of pole pairs (P) is also related to the rotor's structure. Different motor sizes generate varying centrifugal forces during rotor rotation, and the size of the magnetic isolation bridge plays a crucial role in ensuring rotor reliability. These parameters shape the rotor's structural design, determining whether the rotor possesses superior anti-demagnetization properties.

[0025] The inventors of the present invention have found that if the rotor structure design of the motor, the area of ​​the diffusion zone and the size of the magnetic isolation bridge are limited to the relationship in formula (I), and k is limited to i By adding a relatively low content of heavy rare earth elements to the diffusion zone, the anti-demagnetization performance of the motor rotor can be significantly improved. This means that the overall performance of the resulting motor rotor can be maximized while reducing costs. Alternatively, the production cost of the resulting motor rotor can be significantly reduced while maintaining its performance.

[0026] Furthermore, motor rotors that satisfy equation (I) cover a wide range of motor types and sizes commonly used in the market. Therefore, fine-tuning the permanent magnets can significantly improve the performance of motor rotors, both during the manufacturing and operational stages.

[0027] Furthermore, the technical solution provided by the present invention can improve the local anti-demagnetization ability of the magnet without increasing the volume of the permanent magnet (generally, increasing the volume of the permanent magnet can improve the anti-demagnetization ability of the motor rotor to a certain extent) while ensuring demagnetization reliability, thereby improving the anti-demagnetization ability of the motor rotor and reducing the rotor cost.

[0028] According to some embodiments of the present invention, the number of pole pairs P is ≥2.

[0029] According to some embodiments of the present invention, in the V-shaped arrangement, the tip of the V-shape is positioned toward the axis of the iron core, and in the V-shape, the angle between the two permanent magnets is one of an acute angle, a right angle, and an obtuse angle.

[0030] According to some embodiments of the present invention, the number of pole pairs P is ≤ 5, for example, it can be 3, 4 or 5. In a motor rotor in which permanent magnets are arranged in a V shape, one V shape constitutes one pole. For example, when P = 2, there are 4 poles and a total of 8 permanent magnets in the motor rotor.

[0031] According to some embodiments of the present invention, each permanent magnet may include at least one permanent magnet piece. In the permanent magnet, the stacking method of the permanent magnet pieces is not limited, as long as it satisfies the mathematical relationship required by the present invention.

[0032] According to some embodiments of the present invention, the iron core is formed by stacking a plurality of silicon steel sheets.

[0033] Furthermore, the cumulative thickness T is the thickness of the iron core along the axial direction.

[0034] According to some embodiments of the present invention, the cumulative thickness T mm ranges from 50 to 120 mm.

[0035] According to some embodiments of the present invention, the outer diameter D mm of the iron core ranges from 60 to 90 mm.

[0036] By limiting the numerical values ​​of D, T and P, it is equivalent to limiting the size of the motor rotor to the common motor rotors on the market. Within this size range, further limiting the size of the magnetic isolation bridge and the parameters of the diffusion zone is more targeted, and the designed motor rotor has better performance and can better match the current application range and production process of the motor rotor.

[0037] According to some embodiments of the present invention, the magnetization direction of the permanent magnet is radial magnetization.

[0038] According to some embodiments of the present invention, the magnetization direction of the permanent magnet is parallel magnetization.

[0039] According to some embodiments of the present invention, the directions of the magnetic forces in the diffusion region and the non-diffusion region are consistent and are along the length direction of the permanent magnet.

[0040] According to some embodiments of the present invention, the heavy rare earth element includes at least one of Dy and Tb. A higher heavy metal content in a permanent magnet results in a higher coercive force and improved demagnetization resistance. Therefore, increasing the heavy rare earth element content in the diffusion zone can improve the demagnetization resistance of a motor rotor.

[0041] According to some embodiments of the present invention, the number of the diffusion regions is 1 to 5. For example, the diffusion region may include only one diffusion region, or may include 2, 3, 4, or 5 diffusion regions.

[0042] According to some embodiments of the present invention, the diffusion region includes an area of ​​S1 mm 2 The first diffusion zone and area is S2 mm 2 The second diffusion region, and:

[0043]

[0044]

[0045] Among them, 0.01≤k1≤1.2, 0.01≤k2≤1.2.

[0046] It should be noted that as long as a diffusion region is displayed on any cross section, the area of ​​the diffusion region must satisfy the relationship of formula (I).

[0047] According to some embodiments of the present invention, the mass percentage of heavy rare earth in the first diffusion zone is 1.05%-2.0%.

[0048] According to some embodiments of the present invention, the mass percentage of heavy rare earth in the second diffusion zone is 0.59%-1.25%.

[0049] According to some embodiments of the present invention, the contents of heavy rare earth in the first diffusion region and the second diffusion region are equal.

[0050] According to some embodiments of the present invention, the content of heavy rare earth in the first diffusion region is greater than the content of heavy rare earth in the second diffusion region.

[0051] According to some embodiments of the present invention, the content of heavy rare earth in the first diffusion region is less than the content of heavy rare earth in the second diffusion region.

[0052] According to some embodiments of the present invention, the mass percentage of heavy rare earth in the non-diffusion zone is ≤0.53%.

[0053] According to some embodiments of the present invention, the difference in intrinsic coercivity between the diffusion region and the non-diffusion region is 50-200 kA / m.

[0054] According to some embodiments of the present invention, the difference in intrinsic coercivity between the diffusion region and the non-diffusion region is 70-150 kA / m.

[0055] According to some embodiments of the present invention, a method for achieving the difference in intrinsic coercivity between the diffusion region and the non-diffusion region is to reduce the intrinsic coercivity of the non-diffusion region.

[0056] According to some embodiments of the present invention, a method for achieving the difference in intrinsic coercivity between the diffusion region and the non-diffusion region is to increase the intrinsic coercivity of the diffusion region.

[0057] According to some embodiments of the present invention, the heavy rare earth is evenly distributed in the diffusion zone.

[0058] According to some embodiments of the present invention, the distribution of heavy rare earth in the diffusion region is non-uniform.

[0059] Whether the distribution is uniform is related to the method of increasing the content of heavy rare earth. Whether it is uniform has no obvious effect on the performance of the resulting motor rotor. In actual working conditions, whether the distribution of heavy rare earth in the diffusion zone is uniform can be selected according to actual conditions.

[0060] According to some embodiments of the present invention, the heavy rare earth in the diffusion zone is distributed nearly linearly, that is, the distance of a certain position from the edge of the diffusion zone is almost linearly correlated with the concentration of the heavy rare earth in the position.

[0061] According to some embodiments of the present invention, in a certain cross section, the area of ​​the first diffusion region is 1≤S1≤45.

[0062] According to some embodiments of the present invention, in a certain cross section, the area of ​​the first diffusion region is 10≤S1≤15.

[0063] According to some embodiments of the present invention, in a certain cross section, the area of ​​the second diffusion region is 1≤S2≤45.

[0064] According to some embodiments of the present invention, in a certain cross section, the area of ​​the second diffusion region is 10≤S2≤15.

[0065] Generally, a larger diffusion zone area results in greater demagnetization resistance, but also results in higher intrinsic coercivity and required heavy rare earth content, leading to higher costs. However, if the diffusion zone area is too small, demagnetization resistance may not be achieved. Therefore, limiting the diffusion zone area to the above range balances cost and demagnetization resistance. In particular, when S1 = S2 = 10, the resulting motor rotor offers the best price-performance ratio.

[0066] According to some embodiments of the present invention, the first diffusion region is provided at one end of the permanent magnet along the width direction, and the second diffusion region is provided at the other end of the permanent magnet along the width direction.

[0067] According to some embodiments of the present invention, the first diffusion zone is provided at one end of the permanent magnet along the width direction, close to the axis of the iron core, and the second diffusion zone is provided at the other end of the permanent magnet along the width direction, away from the axis of the iron core.

[0068] According to some embodiments of the present invention, the first diffusion region is composed of a plurality of first diffusion sub-regions. Specifically, a plurality of disconnected first diffusion sub-regions are disposed on a side of the permanent magnet close to the core axis. Each first diffusion sub-region has the same heavy rare earth content, and each first diffusion sub-region may have the same or different shapes on the same cross-section.

[0069] According to some embodiments of the present invention, the second diffusion region is composed of a plurality of second diffusion sub-regions. Specifically, a plurality of disconnected second diffusion sub-regions are disposed on a side of the permanent magnet away from the core axis. Each second diffusion sub-region has the same heavy rare earth content, and each second diffusion sub-region may have the same or different shapes on the same cross-section.

[0070] According to some embodiments of the present invention, the diffusion region has the same shape in multiple cross sections.

[0071] That is, the first diffusion region and the second diffusion region are regular in shape, for example, cylindrical or prism-shaped, and run through the length direction of the permanent magnet.

[0072] According to some embodiments of the present invention, the diffusion region has different shapes in at least two cross sections.

[0073] That is, the shapes of the first diffusion region and the second diffusion region are irregular, but still run through the length direction of the permanent magnet.

[0074] Alternatively, the first diffusion zone or (one of) the second diffusion zone does not extend through the length direction of the permanent magnet. For example, the first diffusion zone only extends through half the length of the permanent magnet, and the second diffusion zone extends through the length direction of the permanent magnet. In this case, half of the cross section should only display the second diffusion zone, but not the first diffusion zone.

[0075] According to some embodiments of the present invention, the diffusion region is not included in at least one cross section.

[0076] That is, neither the first diffusion region nor the second diffusion region extends through the length direction of the permanent magnet.

[0077] According to some embodiments of the present invention, the maximum length of the diffusion region in the length direction of the permanent magnet accounts for 25-100% of the length of the permanent magnet, for example, may be 50% or 75%.

[0078] According to some embodiments of the present invention, the diffusion region further includes a third diffusion region.

[0079] According to some embodiments of the present invention, a content of heavy rare earth in the third diffusion region is higher than a content of heavy rare earth in the non-diffusion region.

[0080] According to some embodiments of the present invention, the mass percentage of heavy rare earth in the third diffusion zone is 0.59% to 2.0%.

[0081] According to some embodiments of the present invention, along the width direction of the permanent magnet, the third diffusion region is located between the first diffusion region and the second diffusion region.

[0082] According to some embodiments of the present invention, the third diffusion region consists of one or more third diffusion sub-regions.

[0083] According to some embodiments of the present invention, the third diffusion region has the same shape in multiple cross sections.

[0084] According to some embodiments of the present invention, the third diffusion region has different shapes in at least two cross sections.

[0085] According to some embodiments of the present invention, at least one cross section does not include the third diffusion region.

[0086] According to some embodiments of the present invention, the thickness y1 of the first magnetic isolation bridge is the shortest distance between the slots for accommodating the magnets arranged in a V-shape.

[0087] According to some embodiments of the present invention, the value range of y1 is 0.4≤y1≤0.9, for example, it may be approximately 0.5.

[0088] According to some embodiments of the present invention, the thickness y2 of the second magnetic isolation bridge is the shortest distance between the magnet slot and the edge of the iron core.

[0089] According to some embodiments of the present invention, the value range of y2 is 0.4≤y2≤0.9, for example, it may be approximately 0.5.

[0090] According to an embodiment of the second aspect of the present invention, a permanent magnet motor is provided. The permanent magnet motor includes the motor rotor.

[0091] Since the permanent magnet motor adopts all the technical solutions of the motor rotor of the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment.

[0092] According to some embodiments of the present invention, the permanent magnet motor further includes a rotor surrounding the motor rotor and stator.

[0093] According to an embodiment of the third aspect of the present invention, a compressor is provided, which includes the motor rotor or the permanent magnet motor.

[0094] Since the compressor adopts the permanent magnet motor or all the technical solutions of the permanent magnet motor in the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment.

[0095] According to an embodiment of a fourth aspect of the present invention, a temperature regulating device is provided, wherein the temperature regulating device includes the compressor.

[0096] Since the temperature regulating device adopts all the technical solutions of the compressor of the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment.

[0097] According to some embodiments of the present invention, the temperature regulating device includes at least one of an air conditioner and a refrigerator.

[0098] Unless otherwise specified, the term “about” in the present invention actually means that the error is allowed to be within the range of ±2%, for example, about 100 actually means 100±2%×100.

[0099] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0100] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0101] Figure 1 1 is a schematic structural diagram of the motor rotor in Example 1 of the present invention;

[0102] Figure 2 Schematic diagram of the dimensions of the motor rotor in Example 1 of the present invention;

[0103] Figure 3 is a schematic structural diagram of a permanent magnet motor in Example 9 of the present invention;

[0104] Figure 4 2 is a schematic structural diagram of a motor rotor in Embodiment 2 of the present invention;

[0105] Figure 5 Schematic diagram of the structure of the permanent magnet used in the motor rotor in Example 3 of the present invention;

[0106] Figure 6 yes Figure 5 Schematic diagram of the cross section in the AA` direction;

[0107] Figure 7 yes Figure 5 Schematic diagram of the cross section in the middle BB` direction;

[0108] Figure 8 1 is a schematic structural diagram of a permanent magnet used in a motor rotor in Example 4 of the present invention;

[0109] Figure 9 yes Figure 8 Schematic diagram of the cross section in the AA` direction;

[0110] Figure 10 yes Figure 8 Schematic diagram of the cross section in the middle BB` direction;

[0111] Figure 11 1 is a schematic structural diagram of a permanent magnet used in a motor rotor in Example 5 of the present invention;

[0112] Figure 12 1 is a schematic structural diagram of a permanent magnet used in a motor rotor in Example 6 of the present invention;

[0113] Figure 13 1 is a schematic structural diagram of a permanent magnet used in a motor rotor in Example 7 of the present invention;

[0114] Reference numerals:

[0115] Iron core 110, magnet slot 111;

[0116] Permanent magnet 120, diffusion region 121, first diffusion region 1211, second diffusion region 1212, third diffusion region 1213;

[0117] The magnetic isolation bridge 130 , the first magnetic isolation bridge 131 , and the second magnetic isolation bridge 132 .

[0118] Stator 200. DETAILED DESCRIPTION

[0119] 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.

[0120] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing 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.

[0121] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientation or positional relationship indicated by up, down, etc., are based on the orientation or positional 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 operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0122] 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.

[0123] Example 1

[0124] This embodiment provides a motor rotor, the structure and size of which are as follows: Figures 1-2 As shown, the motor rotor of this embodiment includes:

[0125] The iron core 110 is provided with a magnet slot 111 . The outer diameter of the iron core 110 is D mm and the thickness is T mm.

[0126] The permanent magnets 120 are arranged in a V-shape and disposed in the magnet slot 111 . The permanent magnets 120 include a diffusion region 121 and a non-diffusion region, wherein the content of heavy rare earth in the diffusion region 121 is greater than that in the non-diffusion region.

[0127] The content of heavy rare earth in the first diffusion region 1211 is g1, the content of heavy rare earth in the second diffusion region 1212 is g2, and the content of heavy rare earth in the non-diffusion region is g3;

[0128] The permanent magnet 120 is cut through a plane perpendicular to the axis of the core 110 to obtain a plurality of cross sections;

[0129] In at least one cross section, the diffusion region 121 includes an area of ​​S1 mm 2 The first diffusion region 1211 has an area of ​​S2mm 2 a second diffusion region 1212;

[0130] The magnetic isolation bridge 130 includes a first magnetic isolation bridge 131 with a thickness of y1 mm and a second magnetic isolation bridge 132 with a thickness of y2 mm;

[0131] The first magnetic isolation bridge 131 is provided at the tip of the V-shape, and the second magnetic isolation bridge 132 is provided at a position of the V-shape away from the tip;

[0132] In this embodiment, the number of pole pairs of the rotor is P;

[0133] And the above parameters should satisfy the following formulas (1) to (2);

[0134]

[0135]

[0136] Among them, 0.01≤k1≤1.2, 0.01≤k2≤1.2.

[0137] It can be understood that the iron core 110 is formed by stacking a plurality of silicon steel sheets of the same shape, and finally stacking them into an iron core with a thickness of T mm;

[0138] It is understandable that the heavy rare earth mentioned in the permanent magnet 120 is at least one of Dy and Tb. As long as the corresponding intrinsic coercive force is achieved, one of them or any ratio of the two can be selected in specific production.

[0139] The distribution of the heavy rare earth content in the diffusion zone 121 is not uniform. Specifically, the distance of a certain position in the diffusion zone 121 from the edge of the diffusion zone 121 is almost linearly correlated with the concentration of the heavy rare earth in the position.

[0140] It is further understood that the first diffusion region 1211 is provided at one end of the permanent magnet 120 along the width direction, close to the axis of the core 110 , and the second diffusion region 1212 is provided at the other end of the permanent magnet 120 along the width direction, away from the axis of the core 110 .

[0141] It can be further understood that the shapes of the first diffusion region 1211 and the second diffusion region 1212 are irregular, that is, the shapes of the first diffusion region 1211 and the second diffusion region 1212 on each cross section formed in a direction perpendicular to the axis of the core 110 are irregular, and the shapes of the first diffusion region 1211 and the second diffusion region 1212 may be the same across multiple cross sections.

[0142] It can be further understood that the first diffusion region 1211 and the second diffusion region 1212 run through the length direction of the permanent magnet 120 .

[0143] The size and model of the permanent magnet used in this embodiment are 54.5mm*18mm*2.5mm / 52SH.

[0144] The thickness y1 of the first magnetic isolation bridge 131 is the shortest distance between the magnet slots 111 arranged in a V-shape.

[0145] The thickness y2 of the second magnetic isolation bridge 132 is the shortest distance between the magnet slot 111 and the edge of the iron core 110 .

[0146] Example 2

[0147] This embodiment provides a motor rotor having a structure such as Figure 4 As shown, the motor rotor of this embodiment differs from that of embodiment 1 in that:

[0148] The permanent magnet 120 used in this embodiment forms a third diffusion region 1213 between the first diffusion region 1211 and the second diffusion region 1212;

[0149] The area of ​​the third diffusion region 1213 is S3 mm 2 , of which the content of heavy rare earth is g i , g i >g3.

[0150] It can be understood that the shape of the third diffusion region 1213 is irregular, but the shapes in multiple cross sections are the same and the third diffusion region 1213 runs through the length direction of the permanent magnet 120 .

[0151] and:

[0152]

[0153] Among them, 0.01≤k3≤1.2.

[0154] Example 3

[0155] This embodiment provides a motor rotor. The motor rotor of this embodiment differs from that of Embodiment 1 in that:

[0156] The permanent magnet 120 in Example 1 is replaced by Figures 5-7 The permanent magnet 120 shown; specifically:

[0157] The permanent magnet 120 used in this embodiment includes a first diffusion region 1211 in the shape of a quadrangular prism extending along the length of the permanent magnet 120 , a second diffusion region 1212 in the shape of a quadrangular prism extending along the length of the permanent magnet 120 , and a third diffusion region 1213 consisting of two third diffusion sub-regions.

[0158] It should be noted that the first diffusion region 1211 and the second diffusion region 1212 are distributed at both ends of the width direction of the permanent magnet 120; the two third diffusion sub-regions are respectively located at both ends of the length direction of the permanent magnet 120, and are shaped like quadrangular prisms and do not penetrate the length direction of the permanent magnet 120.

[0159] In this embodiment, the area of ​​the third diffusion region 1213 is S3 mm 2 (When the cross section shows the third diffusion region 1213), the content of heavy rare earth is g i , g i >g3. And:

[0160]

[0161] Among them, 0.01≤k3≤1.2.

[0162] Example 4

[0163] This embodiment provides a motor rotor. The motor rotor of this embodiment differs from that of Embodiment 1 in that:

[0164] The permanent magnet 120 in Example 1 is replaced by Figures 8-10 The permanent magnet 120 shown; specifically:

[0165] In the permanent magnets used in this embodiment:

[0166] The first diffusion region 1211 is composed of two first diffusion sub-regions. Each of the first diffusion sub-regions is in the shape of a quadrangular prism and does not pass through the length direction of the permanent magnet 120. In other words, in the multiple cross sections formed perpendicular to the axis direction of the iron core 110,

[0167] The first diffusion region 1211 is not shown in some cross sections;

[0168] The two first diffusion sub-regions are distributed at both ends of the length direction of the permanent magnet 120;

[0169] The second diffusion region 1212 is similar to the first diffusion region 1211 and is composed of two second diffusion sub-regions. It does not run through the length direction of the permanent magnet 120 but is distributed at both ends of the length direction of the permanent magnet 120 .

[0170] Example 5

[0171] This embodiment provides a motor rotor. The motor rotor of this embodiment differs from that of Embodiment 1 in that:

[0172] The permanent magnet 120 in Example 1 is replaced by Figure 11 The permanent magnet 120 shown; specifically:

[0173] In the permanent magnets used in this embodiment:

[0174] The first diffusion region 1211 and the second diffusion region 1212 are both quadrangular prism-shaped, both pass through the length direction of the permanent magnet 120, and are distributed at both ends of the width direction of the permanent magnet 120;

[0175] In the width direction of the permanent magnet 120, a third diffusion region 1213 is further provided;

[0176] The third diffusion region 1213 does not contact the first diffusion region 1211 or the second diffusion region 1212 , and is in a quadrangular shape, running through the length direction of the permanent magnet 120 .

[0177] In this embodiment, the area of ​​the third diffusion region 1213 is S3 mm 2 , of which the content of heavy rare earth is g i , g i >g3. And:

[0178]

[0179] Among them, 0.01≤k3≤1.2.

[0180] Example 6

[0181] This embodiment provides a motor rotor. The motor rotor of this embodiment differs from that of Embodiment 1 in that:

[0182] The permanent magnet 120 in Example 1 is replaced by Figure 12 The permanent magnet 120 shown; specifically:

[0183] The permanent magnet used in this embodiment does not include the first diffusion region 1211 , but only includes a second diffusion region 1212 in the shape of a quadrangular prism that runs through the length direction of the permanent magnet 120 . The second diffusion region 1212 is located at one end of the width direction of the permanent magnet 120 .

[0184] That is, the area of ​​the second diffusion region only needs to satisfy equation (2).

[0185] Example 7

[0186] This embodiment provides a motor rotor. The motor rotor of this embodiment differs from that of Embodiment 1 in that:

[0187] The permanent magnet 120 in Example 1 is replaced by Figure 13 The permanent magnet 120 shown; specifically:

[0188] The size and model of the permanent magnet used in this embodiment are 54.5mm*18mm*2.5mm / 52SH.

[0189] The first diffusion region 1211 and the second diffusion region 1212 are both in the shape of quadrangular prisms and both extend through the length direction of the permanent magnet 120 .

[0190] The first diffusion region 1211 and the second diffusion region 1212 are distributed at both ends of the permanent magnet 120 in the width direction.

[0191] The first diffusion region 1211 and the second diffusion region 1212 have the same size, which is 54.5 mm*4 mm*2.5 mm.

[0192] The parameters of the motor rotor in this embodiment are shown in Table 1. This embodiment is equivalent to improving the intrinsic coercive force in the diffusion region 121 .

[0193] Substituting the following parameters into equations (1) to (2), we obtain k1 = k2 = 0.1315, which meets the range required by the present invention.

[0194] Example 8

[0195] This embodiment provides a motor rotor. The motor rotor of this embodiment differs from that of Embodiment 7 in that:

[0196] The intrinsic coercivity of the diffusion region 121 and the non-diffusion region is different, and the specific parameters are summarized in Table 1. This embodiment is equivalent to reducing the intrinsic coercivity of the non-diffusion region.

[0197] According to the parameters in Table 1, k1=k2=0.1315 is calculated, which is within the scope of protection required by the present invention.

[0198] Table 1 Summary of rotor parameters in Example 1

[0199]

[0200] Example 9

[0201] This embodiment provides a permanent magnet motor, the specific structure of which is as follows Figure 3 As shown:

[0202] The permanent magnet motor of this embodiment includes the motor rotor in Embodiment 1 and a stator 200 surrounding the motor rotor.

[0203] Embodiments 10 to 16 each provide a permanent magnet motor, which differs from embodiment 9 in that:

[0204] The motor rotor used in the permanent magnet motor of Example 10 is from Example 2;

[0205] The motor rotor used in the permanent magnet motor of Example 11 is from Example 3;

[0206] The motor rotor used in the permanent magnet motor of Example 12 is from Example 4;

[0207] The motor rotor used in the permanent magnet motor of Example 13 is from Example 5;

[0208] The motor rotor used in the permanent magnet motor of Example 14 is from Example 6;

[0209] The motor rotor used in the permanent magnet motor of Example 15 is from Example 7;

[0210] The motor rotor used in the permanent magnet motor of Example 16 comes from Example 8.

[0211] Comparative Example

[0212] This comparative example provides a motor rotor, which differs from Example 7 in that:

[0213] The permanent magnet 120 used does not include the diffusion region 121 .

[0214] That is, the intrinsic coercive force of the permanent magnet 120 at all positions is 1920 kA / m.

[0215] This comparative example also provides a permanent magnet motor, which differs from Example 9 in that:

[0216] The motor rotor used in the permanent magnet motor of this comparative example is from comparative example 1.

[0217] Test example

[0218] This test example tests the anti-demagnetization performance of the motor rotors obtained in Examples 7 to 8 and Comparative Example 1. The specific test method includes the following steps:

[0219] Place the motor rotor at room temperature and measure the initial magnetic flux of the rotor After testing the initial magnetic flux, place the rotor in a constant temperature box for more than 4 hours, and set the temperature of the constant temperature box to the specified temperature;

[0220] The stator (the same as the stator in Examples 9 to 16) is fixed using a device, the DC motor for testing is connected to a DC power supply, and the demagnetization current is set according to a preset demagnetization current value.

[0221] After preparation, remove the rotor from the constant temperature box, install the demagnetization test tooling, and pass a constant DC current through any two-phase windings of the stator. At this time, the two-phase windings of the stator generate a constant magnetic field. Rotate the rotor one circle through the device so that all 6 magnets are demagnetized by the reverse magnetic field (the magnetic field of the energized winding) (this step should be completed within 30 seconds).

[0222] After completion, place the rotor at room temperature for more than 4 hours, and then measure the rotor temperature and magnetic flux after demagnetization After the experiment, the rotor was cooled and the magnetic flux was recorded.

[0223] The test conditions and test results of the anti-demagnetization performance are summarized in Table 2.

[0224] Table 2 Anti-demagnetization performance of the motor rotor in Examples 7-8 and Comparative Example 1

[0225] Example 7 Example 8 Control Example 130℃ / 43A 1.3％ 2.35％ 2.50％ 130℃ / 50A 3.2％ 6.86％ 6.70％

[0226] According to the results in Table 2, the motor rotor provided by the present invention has anti-demagnetization properties that meet industrial requirements by limiting the relationships and values ​​between P, D, T, y1, y2, S1, S2, k1, and k2. Specifically:

[0227] If the diffusion zone is obtained by increasing the intrinsic coercive force of the diffusion zone (Example 7), the anti-demagnetization performance of the obtained motor rotor can be greatly improved with a small cost increase compared to not forming the diffusion zone (Comparative Example 1).

[0228] If a diffusion zone is obtained by reducing the intrinsic coercive force of the non-diffusion zone (Example 8), the anti-demagnetization performance of the resulting motor rotor is comparable to that of a motor without forming a diffusion zone (Comparative Example 1). However, since the intrinsic coercive force of the non-diffusion zone is reduced, that is, the content of heavy rare earth in the non-diffusion zone is reduced, the cost of the permanent magnet in the resulting motor rotor is significantly reduced.

[0229] Furthermore, since the motor rotor provided by the present invention has high anti-demagnetization performance and low cost, the permanent magnet motor, compressor and temperature control equipment including the above-mentioned motor rotor all have the above-mentioned advantages, and further have broad application prospects in industrial and civilian fields.

[0230] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A motor rotor, characterized in that: The motor rotor comprises: An iron core, wherein a magnet slot is provided on the iron core, and the outer diameter of the iron core is D mm and the thickness is T mm; A permanent magnet, the permanent magnets being arranged in a V-shape and disposed in the magnet slot; the permanent magnets comprising at least one diffusion region and a non-diffusion region, the content of heavy rare earth in the diffusion region being greater than the content of heavy rare earth in the non-diffusion region; Cutting the permanent magnet through a plane perpendicular to the axis of the core to obtain a plurality of cross sections; On at least one cross section, the area of ​​any of the diffusion regions is S mm 2 ; A magnetic isolation bridge, wherein the magnetic isolation bridge comprises a first magnetic isolation bridge with a thickness of y1 mm and a second magnetic isolation bridge with a thickness of y2 mm; The first magnetic isolation bridge is provided at the tip of the V-shape, and the second magnetic isolation bridge is provided at a position of the V-shape away from the tip; The number of pole pairs of the rotor is P; and: Where 0.01≤k i ≤1.

2.

2. The rotor according to claim 1, characterized in that The number of the diffusion zones is 1 to 5.

3. The rotor according to claim 2, characterized in that The diffusion zone includes an area of ​​S1 mm 2 The first diffusion zone has an area of ​​S2 mm 2 The second diffusion region, and: Among them, 0.01≤k1≤1.2, 0.01≤k2≤1.

2.

4. The motor rotor according to claim 3, characterized in that: The first diffusion region is provided at one end of the permanent magnet along the width direction, and the second diffusion region is provided at the other end of the permanent magnet along the width direction.

5. The motor rotor according to claim 1, characterized in that: The diffusion region has the same shape in multiple cross sections.

6. The motor rotor according to claim 1, characterized in that: The diffusion regions have different shapes at least in cross section.

7. The motor rotor according to claim 6, characterized in that: The diffusion region is not included in at least one cross section.

8. The motor rotor according to any one of claims 1 to 7, characterized in that: The diffusion region further includes a third diffusion region.

9. The motor rotor according to any one of claims 1 to 7, characterized in that: The heavy rare earth includes at least one of Dy and Tb.

10. A permanent magnet motor, characterized in that: The permanent magnet motor comprises the motor rotor according to any one of claims 1 to 9.

11. A compressor, characterized in that: The compressor comprises the motor rotor according to any one of claims 1 to 9, or the permanent magnet motor according to claim 10.

12. A temperature regulating device, characterized in that: The temperature regulating device comprises the compressor of claim 11 .

13. The temperature regulating device according to claim 12, characterized in that Includes at least one of an air conditioner and a refrigerator.

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