Rotor assembly, motor and compressor

Abstract

The utility model discloses a rotor assembly, a motor and a compressor, belonging to the motor technology field, the rotor assembly comprises a rotor iron core, a plurality of first filling bodies and a plurality of second filling bodies, the rotor iron core is provided with a plurality of first installation grooves used for installing the first filling bodies and a plurality of second installation grooves used for installing the second filling bodies, the plurality of first mounting grooves and the plurality of second mounting grooves are arranged in a staggered manner along the circumferential direction of the rotor iron core, the length of the first filling body is greater than that of the second filling body along the circumferential direction of the rotor iron core, the first filling body is a magnet, the second filling body is a magnet or a non-magnetic material, and the residual magnetism of the first filling body is different from that of the second filling body. The distribution of the magnetic field in the space can be optimized, so that the motor can meet the working condition requirements of high load, low load or high rotating speed.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, and in particular to a rotor assembly, a motor and a compressor. Background Art

[0002] At present, permanent magnet motors include a stator assembly and a rotor assembly. The rotor assembly includes an iron core and multiple permanent magnets. The multiple permanent magnets are arranged in the iron core. Existing permanent magnet motors generally have problems such as low air gap magnetic field intensity and high torque pulsation, resulting in the motor's performance being not good enough under high load, low load or high speed conditions. In addition, the permanent magnets in the motor will undergo irreversible demagnetization when large current passes through, resulting in reduced reliability of the motor. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a rotor assembly that can optimize the spatial distribution of the magnetic field so that the motor can be suitable for high-load, low-load or high-speed working conditions, and can improve the irreversible demagnetization phenomenon of the second filling body when a large current passes through it, and the second filling body's ability to resist irreversible demagnetization is enhanced, thereby improving the reliability of the motor.

[0004] The utility model also provides a motor and a compressor comprising the rotor assembly.

[0005] According to the rotor assembly of the embodiment of the first aspect of the utility model, it includes: a rotor core, which is provided with a plurality of first mounting grooves and a plurality of second mounting grooves, and the plurality of first mounting grooves and the plurality of second mounting grooves are staggered along the circumferential direction of the rotor core; a plurality of first filling bodies and a plurality of second filling bodies, the plurality of first filling bodies are respectively arranged in the plurality of first mounting grooves, and the plurality of second filling bodies are respectively arranged in the plurality of second mounting grooves, along the circumferential direction of the rotor core, the length of the first filling body is greater than the length of the second filling body, the first filling body is a magnet, and the second filling body is a magnet or a non-magnetic material, and the residual magnetism of the first filling body is different from the residual magnetism of the second filling body.

[0006] According to the rotor assembly of the embodiment of the utility model, at least the following beneficial effects are achieved: during production and manufacturing, the remanence of the first filling body or the second filling body can be increased by adjusting the magnetization process, so that the remanence of the first filling body is different from the remanence of the second filling body. Specifically, under high-load working conditions, the remanence of the second filling body can be made greater than the remanence of the first filling body, which can be understood as enhancing the magnetic field of the second filling body. Since the first filling body and the second filling body are arranged alternately, the spatial distribution of the magnetic field can be optimized, so that the strength of the air gap magnetic field of the motor as a whole is enhanced, and the torque pulsation is reduced, which can improve the working performance of the motor. Since the length of the second filling body is less than the length of the first filling body, the spatial layout is optimized, the volume of the motor can be reduced, and the power density of the motor is improved; under low-load or high-speed working conditions, the remanence of the second filling body can be made less than the remanence of the first filling body, which can be understood as weakening the magnetic field of the second filling body. Since the first filling body and the second filling body are arranged alternately, the spatial distribution of the magnetic field will be changed, so that the efficiency of the motor is improved and the speed range is widened. In general, the residual magnetism of the first filling body and the residual magnetism of the second filling body are different from each other, which can be applicable to high load, low load or high speed working conditions.

[0007] According to some embodiments of the present invention, when the second filling body is a magnet, an opening is formed between the second filling body and a side wall of the second mounting slot away from the central axis of the rotor core, and the opening penetrates the rotor core along the axial direction of the rotor core.

[0008] According to some embodiments of the utility model, along the axial projection of the rotor core, the outer contour line of the rotor core includes multiple groups of curved segments, along the radial direction of the rotor core, the multiple groups of curved segments are arranged one by one opposite to the multiple first filling bodies, and each group of the curved segments is symmetrically arranged about the central axis of the first filling body.

[0009] According to some embodiments of the utility model, each group of the curved segments includes two first arc segments and two second arc segments, the two first arc segments and the two second arc segments are symmetrically arranged about the central axis, the center of the first arc segment and the center of the second arc segment do not coincide, and the radius of the first arc segment is greater than or equal to the radius of the second arc segment.

[0010] According to some embodiments of the utility model, the rotor core is provided with an axial hole, the radius of the axial hole is R0, the cross-sectional shape of the first filling body is a rectangle, along the circumference of the rotor core, the length of the first filling body is W1, the minimum distance between the first filling body and the axial hole is H0, the number of the first filling bodies is p, and satisfies: W1=2*(R0+H0)*tan(180° / p).

[0011] According to some embodiments of the present invention, the cross-sectional shapes of the first filling body and the second filling body are both rectangular, along the circumferential direction of the rotor core, the length of the second filling body is W2, along the radial direction of the rotor core, the width of the first filling body is H1, and the number of the first filling bodies is p, satisfying: 0<W2<2*H1*sin(180° / p).

[0012] According to some embodiments of the present invention, the rotor core is provided with an axial hole, the radius of the axial hole is R0, the minimum distance between the first filling body and the axial hole is H0, each group of the curved segments includes a first arc segment and a second arc segment, the radius of the first arc segment is greater than or equal to the radius of the second arc segment, the radius of the first arc segment is R1, along the radial direction of the rotor core, the width of the opening is H3, the minimum distance from the side wall of the opening to the outer peripheral contour line of the rotor core is H4, the width of the second filling body is H2, satisfying: 0<H2<R1-[0.5*W2 / tan(180° / p)+(R0+H0)*cos(180° / p)+H3+H4].

[0013] According to some embodiments of the present invention, in a radial cross section of the rotor core, the cross-sectional area of ​​the first filling body is S1, and the cross-sectional area of ​​the second filling body is S2, satisfying: 0.1≤S2 / S1≤0.3.

[0014] According to some embodiments of the present invention, the remanence of the first filling body is Br1, and the remanence of the second filling body is Br2, satisfying:

[0015] According to some embodiments of the utility model, the outer peripheral wall of the rotor core is provided with a plurality of slots, and the plurality of slots are distributed along the circumference of the rotor core and divided into a plurality of slot groups, each of the slot groups includes at least two slots, and along the radial direction of the rotor core, the plurality of slot groups and the plurality of the first filling bodies are arranged one by one opposite to each other, and at least two slots in each slot group are symmetrically arranged with the axial center axis of the first filling body along the rotor core as the symmetry axis.

[0016] According to some embodiments of the present invention, the width of the slot is less than or equal to 1 / 8 of the circumference of the rotor core, and the depth of the slot is less than or equal to 1 / 2 of the radius of the rotor core.

[0017] The motor according to the second embodiment of the utility model comprises a stator assembly and the rotor assembly described in the first embodiment, wherein a rotor hole is provided in the stator assembly, and the rotor assembly is rotatably disposed in the rotor hole.

[0018] The motor according to the embodiment of the utility model comprises the rotor assembly of the embodiment of the first aspect and thus has at least the above-mentioned beneficial effects, which will not be described in detail here.

[0019] The compressor according to the third aspect of the present invention comprises a stator assembly and the rotor assembly described in the first aspect, wherein a rotor hole is provided in the stator assembly, and the rotor assembly is rotatably disposed in the rotor hole.

[0020] The compressor according to the embodiment of the utility model comprises the rotor assembly of the embodiment of the first aspect and thus has at least the above-mentioned beneficial effects, which will not be described in detail here.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention is further described below with reference to the accompanying drawings and embodiments, wherein:

[0023] Figure 1 It is a schematic diagram of the structure of the rotor assembly and the stator assembly of some embodiments of the utility model;

[0024] Figure 2 It is a schematic diagram of the structure of the rotor assembly of some embodiments of the utility model;

[0025] Figure 3 It is a partial schematic diagram of a rotor core of a rotor assembly of some embodiments of the utility model;

[0026] Figure 4 It is a partial schematic diagram of a rotor assembly of some embodiments of the utility model;

[0027] Figure 5 It is a schematic diagram of the structure of the rotor assembly of some embodiments of the utility model;

[0028] Figure 6 It is a schematic diagram of the structure of the rotor assembly of some embodiments of the utility model;

[0029] Figure 7 Schematic diagram of the demagnetization area of ​​the rotor assembly of the original solution;

[0030] Figure 8 A schematic diagram of a demagnetization region of a rotor assembly in some embodiments of the utility model;

[0031] Fig. 9 It is a comparison diagram of the torque pulsation results of the original solution and some embodiments of the present invention.

[0032] Reference numerals:

[0033] Rotor assembly 100, rotor core 110, first mounting groove 111, second mounting groove 112, opening 113, shaft hole 114, opening 115, first arc segment 116, second arc segment 117, first filling body 120, first trimming 121, second trimming 122, second filling body 130;

[0034] Stator assembly 200 , stator core 210 , rotor hole 211 , stator slot 212 . DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below, and 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 only used to explain the present invention, and cannot be understood as limiting the present invention.

[0036] In the description of the present invention, it should be understood that descriptions involving orientation, 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, and 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, and therefore cannot be understood as a limitation on the present invention.

[0037] In the description of the utility model, if there is a description of first and second, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0038] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. 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.

[0039] Reference Figure 1 As shown, the rotor assembly 100 of the utility model embodiment includes a rotor core 110, a plurality of first filling bodies 120 and a plurality of second filling bodies 130. The plurality of first filling bodies 120 and the plurality of second filling bodies 130 are alternately arranged in the rotor core 110 along the circumferential direction of the rotor core 110, which can also be understood as being staggeredly arranged along the circumferential direction of the rotor core 110.

[0040] Specifically, refer to Figure 1 and Figure 2As shown, the rotor core 110 is a roughly circular ring structure, and the outer edge contour line of the rotor core 110 is roughly circular. The center of the rotor core 110 is provided with an axial hole 114, and the axial hole 114 is used to install the output shaft of the motor. The rotor core 110 has a central axis X1. When working, the rotor core 110 can rotate around the central axis X1. Figure 4 As shown, the rotor core 110 is provided with a first mounting groove 111 and a second mounting groove 112, the first mounting groove 111 is used to mount the first filling body 120, and the second mounting groove 112 is used to mount the second filling body 130. There are multiple first mounting grooves 111, and they are arranged one-to-one with the multiple first filling bodies 120. There are also multiple second mounting grooves 112, and they are arranged one-to-one with the multiple second filling bodies 130. The multiple first mounting grooves 111 and the multiple second mounting grooves 112 are alternately arranged along the circumference of the rotor core 110, which can also be understood as being staggered along the circumference.

[0041] It should be noted that the first filling body 120 is a magnet, which can be understood as a permanent magnet or a magnetic tile. The first filling body 120 will generate a magnetic field, and the second filling body 130 is a magnet or a non-magnetic material. The remanence of the first filling body 120 is different from the remanence of the second filling body 130. The remanence of the first filling body 120 is greater than 0. When the second filling body 130 is a magnet, it can be understood as a permanent magnet or a magnetic tile. The remanence of the second filling body 130 is greater than 0. When the second filling body 130 is a non-magnetic material, the remanence of the second filling body 130 can be understood as equal to 0. In terms of size, in the circumferential direction of the rotor core 110, the length of the first filling body 120 is greater than the length of the second filling body 130. It should be noted that the first filling body 120 can extend in a straight direction and be in a straight bar shape, or it can extend in a circumferential direction and be in an arc bar shape. The second filling body 130 can extend in a straight direction and be in a straight bar shape, or it can extend in a circumferential direction and be in an arc bar shape.

[0042] It should be explained that remanence refers to the fact that after a magnet is magnetized to saturation by an external magnetic field and the external magnetic field is removed, a certain magnetization intensity can still be maintained in the original direction of the external magnetic field. This magnetization intensity is the remanence. Remanence can be represented by the symbol Br. Generally speaking, the magnitude of the magnetic field strength of a magnet can be measured by the magnitude of the remanence. The remanence of the first filling body 120 is Br1, and the remanence of the first filling body 120 is Br2. The remanence of a magnet can be measured by a variety of methods, such as the remanence test method, which uses a remanence test instrument, such as a Tesla meter and a remanence tester, to accurately measure the remanence intensity on a magnet.

[0043] In the above embodiment, according to actual working conditions, during manufacturing, the remanence of the first filling body 120 or the second filling body 130 can be increased by adjusting the magnetization process, so that the remanence Br1 of the first filling body 120 and the remanence Br2 of the second filling body 130 are different. Specifically, under high-load operating conditions, the residual magnetism of the second filling body 130 can be made greater than the residual magnetism of the first filling body 120, that is, Br2 is greater than Br1, which can be understood as enhancing the magnetic field of the second filling body 130. Since the first filling body 120 and the second filling body 130 are arranged alternately, the spatial distribution of the magnetic field can be optimized, so that the strength of the air gap magnetic field of the motor as a whole is enhanced, and the torque pulsation is reduced, which can improve the working performance of the motor. Since the length of the second filling body 130 is smaller than the length of the first filling body 120, the spatial layout is optimized, the volume of the motor can be reduced, and the power density of the motor is improved; under low-load or high-speed operating conditions, the residual magnetism of the second filling body 130 can be made smaller than the residual magnetism of the first filling body 120, that is, Br2 is smaller than Br1, which can be understood as weakening the magnetic field of the second filling body 130. Since the first filling body 120 and the second filling body 130 are arranged alternately, the spatial distribution of the magnetic field will change, the efficiency of the motor will be improved, and the speed range will be widened. In general, it can be applied to high load, low load or high speed working conditions.

[0044] It should be explained that magnetization refers to magnetizing magnetic materials or increasing the magnetism of magnets with insufficient magnetism. The magnetization process is to place the magnetic material in an external magnetic field so that the magnetic moment of the magnetic material is arranged along the direction of the external magnetic field, thereby making the magnetic material magnetic. The greater the strength of the additional external magnetic field, the stronger the magnetization effect on the magnet, and the greater the residual magnetism of the magnet.

[0045] It can be understood that the magnetization direction of the first filling body 120 is along the radial direction of the rotor core 110, and the magnetization direction of the second filling body 130 is along the tangential direction of the rotor core 110, that is, the tangential direction of the rotor core 110. Specifically, Figure 6The direction indicated by the middle arrow is the magnetization direction of the first filling body 120 and the second filling body 130. The magnetization directions of adjacent first filling bodies 120 are opposite, and the magnetization directions of adjacent second filling bodies 130 are opposite, that is, of the two adjacent first filling bodies 120, the magnetization direction of one is along the clockwise tangential direction, and the magnetization direction of the other is along the counterclockwise tangential direction. Of the two adjacent second filling bodies 130, the magnetization direction of one is radially outward, and the magnetization direction of the other first filling body 120 is radially inward, so that two groups of permanent magnets with different magnetic field directions are formed on the rotor core 110, which can reduce the single-pole leakage of each permanent magnet. Furthermore, the magnetic field between two adjacent first filling bodies 120 forms a series magnetic circuit, and the magnetic field generated by the first filling body 120 and the magnetic field generated by the second filling body 130 form a parallel magnetic circuit. Through the magnetic circuit structure combining series and parallel connection, the leakage magnetic flux between adjacent poles is effectively reduced, thereby increasing the magnetic flux density, helping to enhance the air gap magnetic density of the motor, and improving the air gap magnetic field amplitude. Under the same load, the current is smaller, the line loss is reduced, the harmonic magnetic field is suppressed, and the iron loss is reduced, thereby improving the motor performance.

[0046] It is understandable that for a plurality of permanent magnets that are alternately arranged along the circumferential direction and have different residual magnetism, irreversible demagnetization will occur when a large current passes through them, which seriously affects the reliability of the motor.

[0047] It should be noted that irreversible demagnetization refers to the phenomenon that a magnet permanently loses part or all of its magnetism under the influence of external factors. Even if the external factors are removed, the magnetism of the magnet cannot be restored to the state before demagnetization, which is an irreversible phenomenon. If the permanent magnet inside the permanent magnet motor undergoes irreversible demagnetization, it will greatly affect the performance of the motor. Therefore, it is very important to design the internal structure of the motor to improve the irreversible demagnetization of the magnet. There are many external factors that lead to irreversible demagnetization. One of them is that when the permanent magnet motor is running under high current conditions, the high current can be understood as a demagnetization current. The high current will flow through the permanent magnet and generate a reverse magnetic field. The reverse magnetic field will offset the inherent magnetic field of the permanent magnet, resulting in a decrease in the magnetism of the permanent magnet and irreversible demagnetization. If the current is large enough, it may even cause the permanent magnet to be completely demagnetized. This phenomenon is particularly serious when multiple permanent magnets with different remanence are arranged alternately along the circumference.

[0048] Based on this, refer to Figures 2 to 4As shown, in some embodiments, when the second filling body 130 is a magnet, an opening 113 that passes through the rotor core 110 can be arranged on the rotor core 110, and the opening 113 passes through the rotor core 110 axially. The opening 113 is connected to the second mounting slot 112, and the opening 113 is located between the side wall of the second mounting slot 112 and the second filling body 130. It can be understood that the opening 113 is formed by removing a portion of material from the side wall of the second mounting slot 112 away from the central axis X1, that is, the opening 113 is a portion of the second mounting slot 112, and the size of the second mounting slot 112 is enlarged to form the opening 113. When the second filling body 130 is installed in the second mounting slot 112, the second filling body 130 does not completely fill the second mounting slot 112, and the gap formed between the second filling body 130 and the side wall of the second mounting slot 112 can be understood as the opening 113.

[0049] It can be understood that since the air gap magnetic resistance at the opening 113 is larger than the magnetic resistance of the rotor core 110, the reverse magnetic field formed by the demagnetization current is not easy to pass through the opening 113, which changes the spatial distribution of the reverse magnetic field and makes it difficult for the reverse magnetic field to pass through the second filling body 130, thereby improving the irreversible demagnetization phenomenon of the second filling body 130 when a large current passes through it. The second filling body 130's ability to resist irreversible demagnetization is enhanced, ensuring that the magnetic field of the second filling body 130 is not easily affected by the demagnetization current, thereby improving the reliability of the motor and ensuring that the motor can operate stably under high current conditions.

[0050] For the case where a plurality of first filling bodies 120 and a plurality of second filling bodies 130 are arranged alternately, Figure 7 The demagnetization region distribution state of the first filling body 120 and the second filling body 130 is shown when the opening 113 is not arranged in the rotor core 110 . Figure 8 It shows the distribution state of the demagnetization area of ​​the first filling body 120 and the second filling body 130 after the opening 113 is arranged on the rotor core 110. Among them, Demag-Coef (demagnetization coefficient) is the demagnetization coefficient, which is also called the magnetic permeability coefficient. It is an important parameter to describe the demagnetization of the magnet. The demagnetization coefficient is defined as the ratio of the magnetic induction intensity to the demagnetization field intensity. The larger the demagnetization coefficient, the less likely the magnet is to be demagnetized. A one-to-one correspondence is established between the demagnetization coefficient and different colors, and the distribution area of ​​different colors is used to measure the demagnetization degree of the magnet. The darker the color, the smaller the demagnetization coefficient, and the whiter the color, the larger the demagnetization coefficient. Among them, compared with the gray area, the black area has a larger demagnetization coefficient and a stronger anti-demagnetization ability, while the black area has a smaller demagnetization coefficient and a weaker anti-demagnetization ability. The black area can be understood as a demagnetization area.

[0051] By comparison Figure 7 and Figure 8 It can be known that Figure 7 In the figure, when the opening 113 is not arranged, in the radial direction of the rotor core 110, along the direction away from the central axis X1, the color of the second filling body 130 gradually changes from gray to black. It can be understood that the demagnetization area of ​​the second filling body 130 is larger, especially the corner position of the second filling body 130 away from the central axis X1. This is because the reverse magnetic field formed by the demagnetization current passes through the thinner position of the second filling body 130, that is, the corner position of the second filling body 130, in the path of minimum magnetic resistance, resulting in demagnetization at the corner position, and also causing the second filling body 130 The anti-demagnetization ability of the corner position is weaker. Figure 8 In the figure, after arranging the opening 113, the demagnetization area on the second filling body 130 is obviously eliminated, especially at the corner position, that is, the demagnetization coefficient of the second filling body 130 is increased. After analyzing the detailed data, it can be concluded that the demagnetization area is reduced from 7% of the original solution to 1%, and the anti-demagnetization ability of the second filling body 130 is improved, which can improve the reliability of the motor.

[0052] It should be noted that, in some embodiments, the first filling body 120 is made of ferrite material, which can be understood as a ferrite permanent magnet, and the second filling body 130 is a rare earth permanent magnet. The rare earth permanent magnet is made of an intermetallic compound composed of rare earth elements and transition metals. The rare earth permanent magnet has the advantages of high magnetic energy product, high coercive force and high operating temperature. The permanent magnet material with high coercive force is not easily magnetized by large current, thereby improving the anti-demagnetization ability. The rare earth permanent magnet with high magnetic energy product can also generate a stronger magnetic field, improve the working performance of the motor, and is suitable for high-load working conditions. Rare earth permanent magnets can be divided into rare earth cobalt permanent magnets, rare earth nickel permanent magnets, rare earth iron boron permanent magnets, and rare earth aluminum nickel cobalt permanent magnets according to different materials.

[0053] In some embodiments, since the residual magnetism of the second filling body 130 is greater than the residual magnetism of the first filling body 120, the magnetic field provided by the second filling body 130 is strong enough to make the volume of the second filling body 130 smaller than the volume of the first filling body 120, thereby reducing the occupied space, which is beneficial to reducing the volume of the motor and saving the material cost of the second filling body 130.

[0054] Reference Figure 2As shown, in some embodiments, the number of the first installation slots 111 is four, the number of the second installation slots 112 is four, the number of the first filling bodies 120 is four, the number of the second filling bodies 130 is four, the first filling bodies 120 extend in a straight direction and are in a straight strip shape, the four first filling bodies 120 form a square structure, the four second filling bodies 130 are respectively located at the four corners of the above square structure, and the shape of the second filling body 130 is also a roughly square structure. In this embodiment, by reasonably configuring the number of the first filling bodies 120 and the second filling bodies 130, the space of the rotor core 110 can be fully utilized, the spatial layout is optimized, the volume of the motor can be reduced, and the power density of the motor can be improved.

[0055] It should be noted that the first filling body 120 is prone to magnetic leakage. Two adjacent first filling bodies 120 are spaced apart to form a magnetic bridge. The magnetic bridge can be understood as a partial structure of the rotor core 110. The magnetic field lines generated by the first filling body 120 will pass through the magnetic bridge and cause magnetic leakage. Some magnetic lines will not reach the stator, which will lead to a decrease in the utilization rate of the rotor magnetic field and a certain attenuation of the air gap magnetic field amplitude. Based on this, refer to Figure 3 As shown, in some embodiments, two adjacent first filling bodies 120 are spaced apart, and the minimum distance between the two adjacent first filling bodies 120 is W0. In order to reduce the magnetic leakage of the first filling body 120, W0 should be as small as possible, but W0 is not 0, thereby forming a support beam between the two adjacent first filling bodies 120, which can improve the structural strength of the rotor core 110 and improve the supporting effect.

[0056] Reference Figure 3 As shown, in some embodiments, for two adjacent first filling bodies 120, a first trimming edge 121 is provided at a corner position of one of the first filling bodies 120, and a second trimming edge 122 is provided at a corner position of the other first filling body 120. The first trimming edge 121 and the second trimming edge 122 can be understood as being formed by cutting off a portion of the structure at the corner position of the first filling body 120. The first trimming edge 121 and the second trimming edge 122 are close to each other, and the magnetic bridge is located between the first trimming edge 121 and the second trimming edge 122. W0 in the above embodiment can be understood as the minimum distance from the first trimming edge 121 to the second trimming edge 122. The first trimming edge 121 and the second trimming edge 122 can both be straight lines and parallel to each other. The extension direction of the first trimming edge 121 and the second trimming edge 122 can be the same as the length direction of the second filling body 130 in the radial direction. This embodiment can make the two adjacent first filling bodies 120 closer. After the first trimming edge 121 and the second trimming edge 122 are provided, the spatial distribution of the magnetic field of the first filling body 120 can be optimized, and magnetic leakage can be reduced.

[0057] Reference Figure 3As shown, in some embodiments, the first filling body 120 and the second filling body 130 are also arranged at intervals to form a magnetic bridge, and the second filling body 130 extends between two adjacent first filling bodies 120, shortening the distance between the second filling body 130 and the first filling body 120, which can be understood as shortening the thickness of the magnetic bridge, thereby reducing magnetic leakage. The minimum distance between the first filling body 120 and the second filling body 130 is W4. In order to reduce the magnetic leakage of the first filling body 120, W4 should be as small as possible, but W4 is not 0, so that a support beam is formed between the two adjacent first filling bodies 120 and the second filling body 130, which can improve the structural strength of the rotor core 110 and improve the support effect.

[0058] Reference Figure 2 and Figure 3 As shown, according to some embodiments of the utility model, the radius of the shaft hole 114 is R0, and the cross-sectional shape of the first filling body 120 is a rectangle. In the circumferential direction of the rotor core 110, the length of the first filling body 120 is W1. In the radial direction of the rotor core 110, the minimum distance between the first filling body 120 and the shaft hole 114 is H0. The number of first filling bodies 120 is p, and p can be understood as the number of poles of the motor. The above parameters satisfy: W1 = 2*(R0+H0)*tan(180° / p). In this embodiment, the value range of W1 is more appropriate, so that the space on the rotor core 110 can be utilized as much as possible, the distribution of the magnetic field of the first filling body 120 can be optimized, and the efficiency and power density of the motor can be improved.

[0059] Reference Figure 2 and Figure 3 As shown, according to some embodiments of the utility model, the cross-sectional shapes of the first filling body 120 and the second filling body 130 are both rectangular. Along the circumference of the rotor core 110, the length of the first filling body 120 is W1, the length of the second filling body 130 is W2, the width of the first filling body 120 is H1, and the above parameters satisfy: 0<W2<2*H1*sin(180° / p). In this embodiment, the value range of W2 is more appropriate, the space on the rotor core 110 can be used as much as possible, the distribution of the magnetic field of the second filling body 130 can be optimized, and the efficiency and power density of the motor can be improved.

[0060] It should be noted that in the above embodiment, the size of the first filling body 120 is designed according to the optimal magnetic energy product, that is, according to the maximum magnetic flux per unit volume. The magnetic energy product is an indicator of the material's ability to store magnetic energy. The magnetic energy product is defined as the maximum product of the material's magnetic induction intensity (B) and its corresponding magnetizing field (H) during the magnetization process, usually in mega-Gauss-Oersted (MGOe). A higher magnetic energy product indicates that the material can store more magnetic energy in a given volume, which can ensure that the magnetic field of the first filling body 120 is stronger and improve the working performance of the motor.

[0061] In this embodiment, by adjusting the size of the second filling body 130, the air gap magnetic field of the motor can be enhanced to a certain extent. Combined with the magnetic flux density-iron loss curve adopted by the motor, it can be ensured that the magnetic flux density in the motor magnetic circuit is less than the inflection point value of the curve, thereby reducing the volume of the motor, improving the power density, and reducing the electromagnetic loss of the motor, thereby improving the motor efficiency by more than 1%. At the same time, the saturation effect can also be reduced. Saturation refers to the weakening of the ability of the material to respond to further increase in the magnetic field, and saturation will cause magnetic field distortion and reduce motor performance. Working below the inflection point value helps to avoid saturation.

[0062] It should be noted that the magnetic flux density-iron loss curve (also called BH curve or hysteresis loop) is a graphical representation of the relationship between magnetic induction intensity (B) and magnetic field intensity (H). The inflection point value of the magnetic flux density-iron loss curve refers to the point where the magnetic flux density-iron loss curve transitions from its initial linear region to its more nonlinear region, which is usually marked by a sudden change in slope.

[0063] According to some embodiments of the utility model, along the axial cross section of the rotor core 110, the cross-sectional area of ​​the first filling body 120 is S1, and the cross-sectional area of ​​the second filling body 130 is S2, satisfying: 0.1≤S2 / S1≤0.3. It should be explained that since the length of the first filling body 120 in the circumferential direction is greater than the length of the second filling body 130, along the axial cross section of the rotor core 110, S1 will be greater than S2. This embodiment makes the volume distribution ratio of the first filling body 120 and the second filling body 130 more reasonable, thereby reducing the cost of the motor and improving the cost performance of the motor while ensuring the performance of the motor. It can also make the best use of the space on the rotor core 110, optimize the distribution of the magnetic field of the first filling body 120 and the second filling body 130, and improve the efficiency and power density of the motor.

[0064] Based on the above embodiment, the remanence of the first filling body 120 is Br1, and the remanence of the second filling body 130 is Br2, which satisfies: It should be noted that when the second filling body 130 is made of non-magnetic material, Br2 is 0. This makes the remanence and cross-sectional area of ​​each filling body correlated, making the volume distribution ratio of the first filling body 120 and the second filling body 130 more reasonable, thereby reducing the cost of the motor while ensuring the performance of the motor, improving the cost performance of the motor, and making the best use of the space on the rotor core 110, optimizing the distribution of the magnetic field of the first filling body 120 and the second filling body 130, and improving the efficiency and power density of the motor.

[0065] It should be noted that when two magnets with different residual magnetism are arranged alternately along the circumferential direction, it will cause technical problems such as large torque pulsation in the motor, which will in turn cause abnormal vibration and noise.

[0066] Based on this, refer to Figure 1 As shown, according to some embodiments of the utility model, along the axial projection of the rotor core 110, the outer peripheral contour line of the rotor core 110 includes multiple groups of curved segments. It can also be understood that the outer peripheral contour line of the rotor core 110 is composed of multiple groups of curved segments. Specifically, along the circumferential direction of the rotor core 110, multiple groups of curved segments are arranged one by one with multiple first filling bodies 120. Described from another angle, along the radial direction of the rotor core 110, multiple groups of curved segments are arranged one by one with multiple first filling bodies 120. It can be understood that along the radial direction of the rotor core 110, the curved segments are located on the radial outer side, and the first filling body 120 is located on the radial inner side. The first filling body 120 has a central axis X2, and the first filling body 120 is a symmetrical structure. The first filling body 120 is symmetrical about the central axis X2, and the central axis X2 can be understood as a symmetry line. Since the number of the first filling body 120 is multiple, and the multiple first filling bodies 120 are arranged along the circumferential direction, the extension direction of the central axis X2 of each first filling body 120 is different. Each group of curved segments is symmetrically arranged with respect to the central axis X2 of the first filling body 120 corresponding thereto, and the central axis X2 of the first filling body 120 can be understood as the symmetry line of the curved segments.

[0067] In this embodiment, by arranging a curved segment on the outer periphery of the rotor core 110, the curved segment is associated with the position of the first filling body 120, and the distribution of the air gap between the rotor core 110 and the stator core 210 can be changed. By changing the distribution law of the air gap, the harmonic content in the magnetic flux density waveform of the air gap magnetic field can be reduced, and the magnetic flux density waveform of the air gap magnetic field tends to a sine wave, so that the back electromotive force waveform of the motor can tend to a sine wave, which can reduce the torque pulsation of the motor.

[0068] In some embodiments, each group of curve segments may include multiple arc segments, and the centers of two of the arc segments may be concentric or non-concentric. In some other embodiments, each group of curve segments may also include multiple elliptical arc segments or other types of curves or arcs, and each group of curve segments may also include multiple arc segments and multiple elliptical arc segments, which are not limited here.

[0069] Reference Figure 2As shown, according to some embodiments of the utility model, the curved line segment includes a first arc segment 116 and a second arc segment 117, and the number of the first arc segment 116 and the second arc segment 117 are two segments respectively, and the two first arc segments 116 are symmetrical about the central axis X2, and the two second arc segments 117 are symmetrical about the central axis X2. The center of the first arc segment 116 is O0, and the center of the second arc segment 117 is O1. O0 and O1 are not concentrically arranged, and it can also be understood that the center of the first arc segment 116 does not coincide with the center of the second arc segment 117. Specifically, O0 or O1 may deviate from the central axis X1, and one of O0 and O1 has a spacing with the central axis X1, or both O0 and O1 deviate from the central axis X1, and both O0 and O1 have a spacing with the central axis X1.

[0070] Reference Figure 2 As shown, in some embodiments, the radius of the first arc segment 116 is R1, the radius of the second arc segment 117 is R2, the center angle of the first arc segment 116 is θ1, the center angle of the second arc segment 117 is θ2, R1 is greater than R2, θ1 is less than θ2, it can be understood that the arc length of the first arc segment 116 is less than the arc length of the second arc segment 117, and the first arc segment 116 is closer to the central axis X2 relative to the second arc segment 117. It can also be understood that for a group of curved segments, along the circumference of the rotor core 110, the second arc segment 117, the first arc segment 116, the first arc segment 116 and the second arc segment 117 are connected in sequence, a group of curved segments is located between two adjacent second filling bodies 130, and the outer peripheral contour line of the rotor core 110 is composed of four groups of the above-mentioned curved segments. In this embodiment, the arrangement of the curved segments is optimized, the effect is good, and the torque pulsation of the motor can be further reduced.

[0071] Reference Figure 2 and Figure 3As shown, based on the above embodiment, the radius of the shaft hole 114 is R0, the central axis X1 can be understood as the axis of the shaft hole 114, and the minimum distance between the first filling body 120 and the shaft hole 114 is H0. In the circumferential direction of the rotor core 110, the length of the second filling body 130 is W2, and the length of the opening 113 is W3, and W3 can be smaller than W2. In the radial direction of the rotor core 110, the width of the second filling body 130 is H2, the width of the opening 113 is H3, and the minimum distance from the side wall of the opening 113 to the outer peripheral contour line of the rotor core 110 is H4. The above parameters satisfy: 0<H2<R1-[0.5*W2 / tan(180° / p)+(R0+H0)*cos(180° / p)+H3+H4]. In this embodiment, the center O0 can be located on the central axis X1. In this embodiment, by adjusting the size of the second filling body 130, the air gap magnetic field of the motor can be enhanced to a certain extent. Combined with the magnetic flux density-iron loss curve adopted by the motor, it can be ensured that the magnetic flux density in the motor magnetic circuit is less than the inflection point value of the curve, thereby reducing the size of the motor. While increasing the power density, the electromagnetic loss of the motor is also reduced, thereby increasing the motor efficiency by more than 1%.

[0072] It should be noted that other technical means can also be used to reduce the torque pulsation of the motor. Figure 5 As shown, according to some embodiments of the utility model, the outer peripheral wall of the rotor core 110 is provided with a plurality of slots 115, and the plurality of slots 115 are arranged at intervals along the circumferential direction of the rotor core 110, and the plurality of slots 115 can be divided into a plurality of slot groups, each slot group including at least two slots 115. For each slot group, there are two slots 115 arranged symmetrically about the central axis X2 of the first filling body 120. Along the circumferential direction of the rotor core 110, the plurality of slot groups are arranged in a one-to-one correspondence with the plurality of first filling bodies 120. Describing from another angle, it can be understood that along the radial direction of the rotor core 110, the plurality of slot groups are arranged in a one-to-one correspondence with the plurality of first filling bodies 120. That is, for a slot group and a first filling body 120, along the radial direction of the rotor core 110, one slot group is located on the radial outer side, and one first filling body 120 is located on the radial inner side. In some embodiments, the shape of the slot 115 can be square, which is convenient for manufacturing and processing.

[0073] In this embodiment, by arranging a plurality of slots 115 on the outer peripheral wall of the rotor core 110, the positions of the slots 115 are associated with the positions of the first filling bodies 120, and the plurality of slots 115 are periodically distributed according to the number of the first filling bodies 120 (i.e., the number of poles of the motor), the phase of the magnetic flux density waveform of the air gap magnetic field can be changed, and the high-order harmonic components of the magnetic flux density waveform can be reduced, thereby significantly reducing the torque pulsation. In addition, the slots 115 can also save the material used for the rotor core 110, thereby reducing the cost.

[0074] Regarding technical effects, refer to Figure 8 As shown, it is a torque pulsation comparison diagram of the original solution and the embodiment of the utility model after the slot 115 is arranged, Figure 8 The figure depicts the torque function relationship with respect to time, wherein the dashed line segment represents the torque function with respect to time of the original scheme, and the torque peak is larger, resulting in larger torque fluctuation and torque pulsation. The solid line segment represents the torque function with respect to time of the embodiment of the utility model. After the structure of the slot 115 is arranged, the torque peak is greatly reduced compared with the dashed line segment function, and the torque is relatively stable, so the torque pulsation becomes relatively stable. According to the data obtained from the actual experience calculation, the torque pulsation is reduced from 16.3% of the original scheme to 4.8% of the utility model.

[0075] Reference Figure 5 As shown, according to some embodiments of the utility model, the width of the slot 115 in the circumferential direction of the rotor core 110 is less than or equal to 1 / 8 of the circumference of the rotor core 110, and the depth of the slot 115 in the radial direction of the rotor core 110 is less than or equal to 1 / 2 of the radius of the rotor core 110. In this embodiment, the size of the slot 115 is adjusted to be associated with the circumference and radius of the rotor core 110, so as to further optimize the magnetic field.

[0076] Some embodiments of the present invention also provide a motor, referring to Figure 1 As shown, the motor includes a stator assembly 200 and a rotor assembly 100 of the above embodiment, the stator assembly 200 includes a stator core 210, a rotor hole 211 is provided in the stator core 210, the rotor assembly 100 is arranged in the rotor hole 211, and the rotor assembly 100 can rotate around the central axis X1, and there is a gap between the rotor assembly 100 and the stator core 210. The inner periphery of the stator core 210 is provided with a plurality of stator slots 212 arranged along the circumferential direction, and the stator slots 212 are used to install the winding. The rotor core 110 is a sheet structure, which can be made of silicon steel sheets or other metal sheets with good magnetic conductivity, and has the advantage of low cost. The number of rotor cores 110 is multiple, and the multiple rotor cores 110 are stacked and arranged along the central axis X1. Along the direction of the central axis, the thickness of the first filling body 120 and the thickness of the second filling body 130 are both greater than the thickness of the rotor core 110. The first filling body 120 will pass through the first installation slot 111 of the multiple rotor cores 110, and the second filling body 130 will pass through the second installation slot 112 of the multiple rotor cores 110. In some embodiments, in the axial direction of the rotor core 110, the thickness of the first filling body 120 and the thickness of the second filling body 130 can be the same, and in the thickness direction, the two end faces of the first filling body 120 are respectively flush with the two end faces of the second filling body 130, so as to facilitate the installation of the multiple rotor cores 110.

[0077] Due to the adoption of the rotor assembly 100 of the above-mentioned embodiment, the working performance of the motor of this embodiment is relatively excellent and can be applied to working conditions such as high load, low load or high speed. In addition, the anti-irreversible demagnetization capability of the second filling body 130 is enhanced, thereby improving the reliability of the motor.

[0078] Some embodiments of the utility model also provide a compressor, which includes the motor of the above embodiment. The compressor can be used in refrigeration equipment such as air conditioners and refrigerators, so that the above refrigeration equipment has good working performance and reliability and can be applied to a variety of different working conditions.

[0079] Of course, the present invention is not limited to the above-mentioned embodiments, and technicians familiar with the field may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A rotor assembly, characterized in that: include: The rotor core is provided with a plurality of first mounting grooves and a plurality of second mounting grooves, wherein the plurality of first mounting grooves and the plurality of second mounting grooves are arranged alternately along the circumferential direction of the rotor core; There are multiple first filling bodies and multiple second filling bodies, wherein the multiple first filling bodies are respectively arranged in the multiple first mounting grooves, and the multiple second filling bodies are respectively arranged in the multiple second mounting grooves. Along the circumference of the rotor core, the length of the first filling body is greater than the length of the second filling body. The first filling body is a magnet, and the second filling body is a magnet or a non-magnetic material. The residual magnetism of the first filling body is different from the residual magnetism of the second filling body.

2. The rotor assembly according to claim 1, characterized in that: When the second filling body is a magnet, an opening is formed between the second filling body and a side wall of the second mounting groove away from the central axis of the rotor core, and the opening penetrates the rotor core along the axial direction of the rotor core.

3. The rotor assembly according to claim 2, characterized in that: Along the axial projection of the rotor core, the outer contour line of the rotor core includes multiple groups of curved segments. Along the radial direction of the rotor core, the multiple groups of curved segments are arranged one by one opposite to the multiple first filling bodies, and each group of curved segments is symmetrically arranged about the central axis of the first filling body.

4. The rotor assembly according to claim 3, characterized in that: Each group of the curved segments includes two first arc segments and two second arc segments, the two first arc segments and the two second arc segments are symmetrical about the central axis, the center of the first arc segment does not coincide with the center of the second arc segment, and the radius of the first arc segment is greater than or equal to the radius of the second arc segment.

5. The rotor assembly according to claim 1, characterized in that: The rotor core is provided with an axial hole, the radius of the axial hole is R0, the cross-sectional shape of the first filling body is a rectangle, along the circumference of the rotor core, the length of the first filling body is W1, the minimum distance between the first filling body and the axial hole is H0, the number of the first filling bodies is p, satisfying: W1=2*(R0+H0)*tan(180° / p).

6. The rotor assembly according to claim 3, characterized in that: The cross-sectional shapes of the first filling body and the second filling body are both rectangular. Along the circumferential direction of the rotor core, the length of the second filling body is W2, and along the radial direction of the rotor core, the width of the first filling body is H1. The number of the first filling bodies is p, satisfying: 0<W2<2*H1*sin(180° / p).

7. The rotor assembly according to claim 6, characterized in that The rotor core is provided with an axial hole, the radius of the axial hole is R0, the minimum distance between the first filling body and the axial hole is H0, each group of the curved segments includes a first arc segment and a second arc segment, the radius of the first arc segment is greater than or equal to the radius of the second arc segment, the radius of the first arc segment is R1, along the radial direction of the rotor core, the width of the opening is H3, the minimum distance from the side wall of the opening to the outer peripheral contour line of the rotor core is H4, the width of the second filling body is H2, satisfying: 0<H2<R1-[0.5*W2 / tan(180° / p)+(R0+H0)*cos(180° / p)+H3+H4].

8. The rotor assembly according to claim 1, characterized in that In a radial cross section of the rotor core, the cross-sectional area of ​​the first filling body is S1, and the cross-sectional area of ​​the second filling body is S2, satisfying: 0.1≤S2 / S1≤0.

3.

9. The rotor assembly according to claim 8, characterized in that The remanent magnetism of the first filling body is Br1, and the remanent magnetism of the second filling body is Br2, satisfying:

10. The rotor assembly according to claim 1, characterized in that The outer peripheral wall of the rotor core is provided with a plurality of slots, and the plurality of slots are distributed along the circumference of the rotor core and divided into a plurality of slot groups, each of the slot groups includes at least two slots, and along the radial direction of the rotor core, the plurality of slot groups and the plurality of the first filling bodies are arranged one by one opposite to each other, and at least two slots in each slot group are symmetrically arranged with the central axis of the first filling body along the axial direction of the rotor core as the symmetry axis.

11. The rotor assembly according to claim 10, characterized in that The width of the slot is less than or equal to 1 / 8 of the circumference of the rotor core, and the depth of the slot is less than or equal to 1 / 2 of the radius of the rotor core.

12. A motor, characterized in that: It comprises a stator assembly and a rotor assembly according to any one of claims 1 to 11, wherein a rotor hole is provided in the stator assembly, and the rotor assembly is rotatably disposed in the rotor hole.

13. A compressor, characterized in that: It comprises a stator assembly and a rotor assembly according to any one of claims 1 to 11, wherein a rotor hole is provided in the stator assembly, and the rotor assembly is rotatably disposed in the rotor hole.

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