Motor rotor, motor and mechanical structure

Abstract

The present invention provides a motor rotor, a motor and a mechanical structure. The motor rotor includes a rotor body, on which a first permanent magnetic pole and a second permanent magnetic pole are arranged alternately along the circumference of the rotor body, the first permanent magnetic pole includes at least two magnetic steels with different coercive forces, a first low coercive force magnetic steel and a first high coercive force magnetic steel arranged in series are arranged in the middle of the first permanent magnetic pole, and a second low coercive force magnetic steel is arranged on both sides of the first permanent magnetic pole. After the present invention uses the first low coercive force magnetic steel and the first high coercive force magnetic steel in series, the anti-demagnetization ability of the first low coercive force magnetic steel is improved, so in the magnetic demagnetization process, a relatively large demagnetization current can be applied to enable the second low coercive force magnetic steel to achieve reverse magnetization, reduce the entire motor magnetic flux, and improve the magnetic adjustment range of the motor.

Description

Technical Field

[0001] The present invention relates to the technical field of drive devices, and in particular to a motor rotor, a motor and a mechanical structure. Background Art

[0002] Traditional permanent magnet motors rely on permanent magnets to provide magnetic flux, but the magnetic field provided by permanent magnets is fixed, and the magnetic field inside the motor is difficult to adjust, making it difficult for permanent magnet motors to balance efficiency at high and low frequencies. And when the power supply voltage is fixed, the maximum operating frequency of the motor is limited.

[0003] At present, most permanent magnet motors have the disadvantage that the magnetic field is difficult to adjust, which leads to the maximum speed of the motor being limited by factors such as the input DC bus voltage, and the efficiency of the motor in low-speed and high-speed operation areas is difficult to balance. During the operation of the motor, the low-coercive force magnetic steel is affected by the high-coercive force magnetic steel, and the charging and demagnetization current is large, which will increase the difficulty of charging and demagnetizing the low-coercive force magnetic steel and reduce the efficiency of the motor.

[0004] In addition, some existing permanent magnet motors have solved the problem of large magnetizing current, but they still have the problem of small demagnetization current and the risk of demagnetization during normal operation. There are also some permanent magnet motors that have solved the problem of small demagnetization current, but the magnetic adjustment range of such series structures is small. Summary of the invention

[0005] The main purpose of the present invention is to provide a motor rotor, a motor and a mechanical structure to solve the problem of small magnetic field adjustment range of permanent magnet motors in the prior art.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a motor rotor is provided, including a rotor body, on which a first permanent magnet pole and a second permanent magnet pole are arranged alternately along the circumference of the rotor body, the first permanent magnet pole and the second permanent magnet pole are arranged alternately along the circumference of the rotor body, the first permanent magnet pole includes at least two magnetic steels with different coercive forces, a first low-coercive force magnetic steel and a first high-coercive force magnetic steel arranged in series are arranged in the middle of the first permanent magnet pole, and the second low-coercive force magnetic steel is arranged on both sides of the first permanent magnet pole.

[0007] Furthermore, the magnetic steel of the second permanent magnet pole is a second high coercive force magnetic steel.

[0008] Further, the coercive force of the first high-coercive force magnetic steel and the second high-coercive force magnetic steel are the same or different. When the coercive force of the first high-coercive force magnetic steel and the second high-coercive force magnetic steel are different, the difference in the coercive force of the first high-coercive force magnetic steel and the second high-coercive force magnetic steel is within 20%.

[0009] Further, the coercive force of the first low-coercive force magnetic steel and the second low-coercive force magnetic steel are the same or different. When the coercive force of the first low-coercive force magnetic steel and the second low-coercive force magnetic steel are different, the difference in the coercive force of the first low-coercive force magnetic steel and the second low-coercive force magnetic steel is within 20%.

[0010] Furthermore, the first permanent magnet poles are arranged in a straight line and are symmetrically arranged about the magnetic pole center line of the first permanent magnet poles; the second permanent magnet poles are arranged in a straight line, a V shape or a W shape and are symmetrically arranged about the magnetic pole center line of the second permanent magnet poles.

[0011] Furthermore, the first low-coercive force magnetic steel and the first high-coercive force magnetic steel are arranged close to each other or separated by a predetermined gap.

[0012] Further, in the first permanent magnet pole, the offset distance between the first low coercive force magnetic steel and the second low coercive force magnetic steel in the radial direction of the motor rotor is H, the width of the second low coercive force magnetic steel in the radial direction of the motor rotor is H2, the width of the first low coercive force magnetic steel in the radial direction of the motor rotor is H3, the width of the first high coercive force magnetic steel in the radial direction of the motor rotor is H4, and the width of the second high coercive force magnetic steel in the radial direction of the motor rotor is H1, wherein, -0.5H2≤H≤H3, 1.5H2≥H3≥H2; 0.5H2≥H4≥0.2H2, H2≥1.2H1.

[0013] Furthermore, the length of the second low coercive force magnetic steel is L2, the length of the first high coercive force magnetic steel is L4, the length of the first low coercive force magnetic steel is L3, and the length of the second high coercive force magnetic steel is L1, wherein 1.1L4≥L3≥L4; 3.3L3≥2L2≥3L3, L1≤2L2+L3.

[0014] Furthermore, the first low coercive force magnetic steel is AlNiCo magnetic steel.

[0015] According to another aspect of the present invention, a motor is provided, comprising a motor rotor, wherein the motor rotor is the above-mentioned motor rotor.

[0016] According to yet another aspect of the present invention, a mechanical structure is provided, comprising a motor, wherein the motor is the motor described above.

[0017] By applying the technical solution of the present invention, a structure in which a first low coercive force magnetic steel and a first high coercive force magnetic steel are partially connected in series is adopted in the present application. The first high coercive force magnetic steel has a magnetic-assisting effect on the first low coercive force magnetic steel, and the coercive force displayed to the outside is improved, thereby ensuring that the anti-demagnetization ability of the first low coercive force magnetic steel is improved, so that the first low coercive force magnetic steel is not affected by the demagnetization current during the flux change process, and the residual magnetism remains unchanged. Therefore, when the second low coercive force magnetic steel plays a magnetic adjustment role during the flux change process, the magnetic direction of the second low coercive force magnetic steel changes, and the magnetism of the first low coercive force magnetic steel remains unchanged, and does not play a magnetic adjustment role.

[0018] It can be seen that after the first low coercive force magnetic steel and the first high coercive force magnetic steel are connected in series in the present invention, the anti-demagnetization ability of the first low coercive force magnetic steel is improved. Therefore, in the magnetic adjustment and demagnetization process, a relatively large demagnetization current can be applied to enable the second low coercive force magnetic steel to achieve reverse magnetization and reduce the magnetic flux of the entire motor. In the conventional structure, the first high coercive force magnetic steel is not provided with a magnetizing assist, and a structure in which too large a demagnetization current cannot be applied, so the demagnetization of the second low coercive force magnetic steel is limited, and the magnetic adjustment range is also limited. The structure of the motor rotor in the present invention can effectively improve the magnetic adjustment range. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0020] Figure 1 The front view of the motor rotor of the present invention is schematically shown;

[0021] Figure 2 The dimensioning diagram of each structure of the motor rotor of the present invention is schematically shown.

[0022] The above drawings include the following reference numerals:

[0023] 10. rotor body; 11. first permanent magnet pole; 111. first low coercive force magnetic steel; 112. second low coercive force magnetic steel; 113. first high coercive force magnetic steel; 12. second permanent magnet pole; 121. second high coercive force magnetic steel. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations, and the spatially relative descriptions used herein are interpreted accordingly.

[0027] See also Figure 1 to Figure 2 As shown, according to an embodiment of the present invention, a motor is provided. The motor in this embodiment particularly refers to a variable flux motor.

[0028] However, the magnetic field adjustment range of the existing variable flux motor is relatively small. Therefore, the structure of the motor rotor of the motor is improved in the present application.

[0029] Specifically, the motor rotor in the present embodiment includes a rotor body 10, on which a first permanent magnetic pole 11 and a second permanent magnetic pole 12 are arranged, the first permanent magnetic pole 11 and the second permanent magnetic pole 12 are arranged alternately along the circumference of the rotor body 10, the first permanent magnetic pole 11 includes at least two magnetic steels with different coercive forces, wherein a first low coercive force magnetic steel 111 and a first high coercive force magnetic steel 113 arranged in series are arranged in the middle of the first permanent magnetic pole 11, and a second low coercive force magnetic steel 112 is arranged on both sides of the first permanent magnetic pole 11. It should be noted that the arrangement of the first high coercive force magnetic steel 113 and the first low coercive force magnetic steel 111 in series in the present embodiment means that the magnetic force lines flow from the first low coercive force magnetic steel 111 to the first high coercive force magnetic steel 113, that is, the equivalent circuit diagram of the motor is the arrangement of the first high coercive force magnetic steel 113 and the first low coercive force magnetic steel 111 in series.

[0030] In the present application, a structure of partially connecting the first low-coercive force magnetic steel 111 and the first high-coercive force magnetic steel 113 in series is adopted. The first high-coercive force magnetic steel 113 has a magnetic-assisting effect on the first low-coercive force magnetic steel 111, and the coercive force displayed to the outside is improved, thereby ensuring that the anti-demagnetization ability of the first low-coercive force magnetic steel 111 is improved, so that the first low-coercive force magnetic steel 111 is not affected by the demagnetization current during the flux change process, and the residual magnetism remains unchanged. Therefore, when the second low-coercive force magnetic steel 112 plays a magnetic adjustment role during the flux change process, the magnetic direction of the second low-coercive force magnetic steel 112 changes, and the magnetism of the first low-coercive force magnetic steel 111 remains unchanged, and does not play a magnetic adjustment role.

[0031] It can be seen that after the first low-coercive force magnetic steel 111 and the first high-coercive force magnetic steel 113 are connected in series in this embodiment, the anti-demagnetization ability of the first low-coercive force magnetic steel 111 is improved. Therefore, in the magnetic adjustment and demagnetization process, a relatively large demagnetization current can be applied to enable the second low-coercive force magnetic steel 112 to achieve reverse magnetization and reduce the magnetic flux of the entire motor. In the conventional structure, the first high-coercive force magnetic steel 113 is not provided to assist magnetization, and a structure in which too large a demagnetization current cannot be applied, so the demagnetization of the second low-coercive force magnetic steel 112 is limited, and the magnetic adjustment range is also limited. The structure of the motor rotor in this embodiment can effectively improve the magnetic adjustment range.

[0032] In this embodiment, the magnetic steel of the second permanent magnetic pole 12 is the second high coercive force magnetic steel 121. In actual design, the first permanent magnetic pole 11 and the second permanent magnetic pole 12 are arranged in a straight line and symmetrically arranged about the corresponding magnetic pole center line, which can increase the effective magnetic flux area of ​​the magnetic pole adjustment magnetic steel. Of course, in other embodiments of the present invention, the second permanent magnetic pole 12 can also be set to a V-shape or a W-shape. As long as it is other deformation methods under the conception of the present invention, they are all within the protection scope of the present invention.

[0033] In actual design, the coercive force of the first high coercive force magnetic steel 113 and the second high coercive force magnetic steel 121 in this embodiment can be the same or different. When the coercive force of the first high coercive force magnetic steel 113 and the second high coercive force magnetic steel 121 are different, the coercive force of the second high coercive force magnetic steel 121 is higher than the coercive force of the first high coercive force magnetic steel 113, but the difference in coercive force is within 20%.

[0034] Similarly, in this embodiment, the coercive force of the first low-coercive force magnetic steel 111 and the second low-coercive force magnetic steel 112 may be the same or different. When the coercive force of the first low-coercive force magnetic steel 111 and the second low-coercive force magnetic steel 112 are different, the difference in the coercive force of the first low-coercive force magnetic steel 111 and the second low-coercive force magnetic steel 112 is within 20%, which can effectively improve the anti-demagnetization ability of the magnetic steel 3.

[0035] Compared with the first high coercive force magnetic steel 113 and the second high coercive force magnetic steel 121, the first low coercive force magnetic steel 111 and the second low coercive force magnetic steel 112 in this embodiment are relatively low. For example, if the coercive force of the first low coercive force magnetic steel 111 and the second low coercive force magnetic steel 112 is set to about 100 A / m, the corresponding coercive force of the first high coercive force magnetic steel 113 and the second high coercive force magnetic steel 121 is about 1000 A / m, which is actually designed according to the specific needs of the motor.

[0036] During the demagnetization process of the motor in this embodiment, a sufficiently large current can be applied to change the magnetism of the second low coercive force magnetic steel 112 so that it reaches the reverse direction, and the anti-demagnetization ability of the first low coercive force magnetic steel 111 is improved. During the flux change process, the second low coercive force magnetic steel 112 is not affected by the demagnetization current, and the residual magnetism remains unchanged; therefore, in the entire magnetic adjustment process, only the second low coercive force magnetic steel 112 plays a magnetic adjustment role, and the magnetic direction of the second low coercive force magnetic steel 112 changes; and since the first low coercive force magnetic steel 111 is arranged in series with the first high coercive force magnetic steel 113, the first high coercive force magnetic steel 113 has a magnetic-assisting effect on the first low coercive force magnetic steel 111, and the coercive force is shown to be improved externally, so the magnetism remains unchanged during the magnetic adjustment process, and it does not play a magnetic adjustment role in the entire process, thereby achieving the effect of increasing the magnetic adjustment range of the motor and increasing the magnetic adjustment multiple of the motor.

[0037] See again Figure 1 and Figure 2 As shown, in the first permanent magnet pole 11, the offset distance between the first low coercive force magnetic steel 111 and the second low coercive force magnetic steel 112 in the radial direction of the motor rotor is H, the width of the second low coercive force magnetic steel 112 in the radial direction of the motor rotor is H2, the width of the first low coercive force magnetic steel 111 in the radial direction of the motor rotor is H3, the width of the first high coercive force magnetic steel 113 in the radial direction of the motor rotor is H4, and the width of the second high coercive force magnetic steel 121 in the radial direction of the motor rotor is H1, wherein, -0.5H2≤H≤H3, 1.5H2≥H3≥H2; 0.5H2≥H4≥0.2H2, H2≥1.2H1. Preferably, the length of the second low coercive force magnetic steel 112 is L2, the length of the first high coercive force magnetic steel 113 is L4, the length of the first low coercive force magnetic steel 111 is L3, and the length of the second high coercive force magnetic steel 121 is L1, wherein 1.1L4≥L3≥L4; 3.3L3≥2L2≥3L3, L1≤2L2+L3. Under this size arrangement, the motor magnetic adjustment range in this embodiment is maximized and the charging and demagnetization current is optimized.

[0038] Preferably, the first low-coercive force magnetic steel 111 , the second low-coercive force magnetic steel 112 , the first high-coercive force magnetic steel 113 and the second high-coercive force magnetic steel 121 in this embodiment may all be AlNiCo magnetic steel.

[0039] Preferably, the first low-coercive force magnetic steel 111 and the first high-coercive force magnetic steel 113 in this embodiment can be arranged close to each other, or can be arranged with a predetermined gap. It should be noted that the predetermined gap arrangement in this embodiment means that they can be placed in one magnetic steel slot. The first low-coercive force magnetic steel 111 and the first high-coercive force magnetic steel 113 can also be placed in two magnetic steel slots respectively, and there is an iron core between the first low-coercive force magnetic steel 111 and the first high-coercive force magnetic steel 113, and the iron core structure can be separated from the rotor or integrated.

[0040] According to another aspect of the present invention, a mechanical structure is provided, and the mechanical structure particularly refers to products suitable for wide-band operation, such as compressors and washing machines. The mechanical structure includes the motor in the above embodiment.

[0041] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: during the demagnetization process of the motor, a sufficiently large current can be applied to change the magnetism of the second low coercive force magnetic steel 112 so that it reaches the reverse direction, the anti-demagnetization ability of the first low coercive force magnetic steel 111 is improved, and the second low coercive force magnetic steel 112 is not affected by the demagnetization current during the flux change process, and the residual magnetism remains unchanged; therefore, in the entire magnetic adjustment process, only the second low coercive force magnetic steel 112 plays a magnetic adjustment role, and the magnetic direction of the second low coercive force magnetic steel 112 changes; and since the first low coercive force magnetic steel 111 is arranged in series with the first high coercive force magnetic steel 113, the first high coercive force magnetic steel 113 has a magnetic-assisting effect on the first low coercive force magnetic steel 111, and the coercive force is shown to be improved externally, so the magnetism remains unchanged during the magnetic adjustment process, and does not play a magnetic adjustment role in the entire process, thereby achieving the effect of increasing the magnetic adjustment range of the motor and increasing the magnetic adjustment multiple of the motor.

[0042] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A motor rotor, characterized in that: The invention comprises a rotor body (10), wherein a first permanent magnetic pole (11) and a second permanent magnetic pole (12) are arranged on the rotor body (10), wherein the first permanent magnetic pole (11) and the second permanent magnetic pole (12) are alternately arranged along the circumference of the rotor body (10), wherein the first permanent magnetic pole (11) comprises at least two magnetic steels with different coercive forces, wherein a first low-coercive force magnetic steel (111) and a first high-coercive force magnetic steel (113) arranged in series are arranged in the middle of the first permanent magnetic pole (11), and the second low-coercive force magnetic steel (112) is arranged on both sides of the first permanent magnetic pole (11); The magnetic steel of the second permanent magnetic pole (12) is a second high coercive force magnetic steel (121); The length of the second low coercive force magnetic steel (112) is L2, the length of the first high coercive force magnetic steel (113) is L4, the length of the first low coercive force magnetic steel (111) is L3, and the length of the second high coercive force magnetic steel (121) is L1, wherein 1.1L4≥L3≥L4; 3.3L3≥2L2≥3L3, L1≤(2L2+L3).

2. The motor rotor according to claim 1, characterized in that: The coercive forces of the first high-coercive-force magnetic steel (113) and the second high-coercive-force magnetic steel (121) are the same or different. When the coercive forces of the first high-coercive-force magnetic steel (113) and the second high-coercive-force magnetic steel (121) are different, the difference in coercive forces between the first high-coercive-force magnetic steel (113) and the second high-coercive-force magnetic steel (121) is within 20%.

3. The motor rotor according to claim 1, characterized in that: The coercive forces of the first low-coercive force magnetic steel (111) and the second low-coercive force magnetic steel (112) are the same or different. When the coercive forces of the first low-coercive force magnetic steel (111) and the second low-coercive force magnetic steel (112) are different, the difference in coercive forces between the first low-coercive force magnetic steel (111) and the second low-coercive force magnetic steel (112) is within 20%.

4. The motor rotor according to claim 1, characterized in that: The first permanent magnetic poles (11) are arranged in a straight line and are symmetrically arranged about a magnetic pole center line of the first permanent magnetic pole (11); the second permanent magnetic poles (12) are arranged in a straight line, a V shape or a W shape and are symmetrically arranged about a magnetic pole center line of the second permanent magnetic pole (12).

5. The motor rotor according to claim 1, characterized in that: The first low-coercive force magnetic steel (111) and the first high-coercive force magnetic steel (113) are arranged close to each other or separated by a predetermined gap.

6. The motor rotor according to claim 1, characterized in that: In the first permanent magnet pole (11), the offset distance between the first low coercive force magnetic steel (111) and the second low coercive force magnetic steel (112) in the radial direction of the motor rotor is H, the width of the second low coercive force magnetic steel (112) in the radial direction of the motor rotor is H2, the width of the first low coercive force magnetic steel (111) in the radial direction of the motor rotor is H3, the width of the first high coercive force magnetic steel (113) in the radial direction of the motor rotor is H4, and the width of the second high coercive force magnetic steel (121) in the radial direction of the motor rotor is H1, wherein -0.5H2≤H≤H3, 1.5H2≥H3≥H2; 0.5H2≥H4≥0.2H2, H2≥1.2H1.

7. The motor rotor according to any one of claims 1 to 6, characterized in that: The first low coercive force magnetic steel (111) is AlNiCo magnetic steel.

8. A motor, comprising a motor rotor, characterized in that: The motor rotor is the motor rotor according to any one of claims 1 to 7.

9. A mechanical structure comprising a motor, characterized in that: The motor is the motor according to claim 8.

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