Permanent magnet motor and compressor

Abstract

The utility model provides a permanent magnet motor and a compressor, the permanent magnet motor comprises a rotor assembly, the rotor assembly comprises a rotor iron core and a plurality of permanent magnet groups, each permanent magnet group comprises two permanent magnets, and each permanent magnet is embedded in the rotor iron core; the stator assembly is arranged around the rotor assembly; wherein the structure of the permanent magnet motor meets the condition that S * P * R1 / R2 is larger than or equal to 20 and smaller than or equal to 29, S is the projection area of any permanent magnet in a preset plane, the preset plane is perpendicular to the axial direction of the permanent magnet motor, P is the number of pole pairs of the rotor assembly, R1 is the radius of an inscribed circle of the stator assembly, and R2 is the radius of a circumscribed circle of the stator assembly. The permanent magnet motor provided by the utility model solves the technical problem that the permanent magnet motor in the related technology is difficult to consider both the performance and the cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to the motor field, specifically, a kind of permanent magnet motor and compressor. BACKGROUND

[0002] Now, permanent magnet motor has universal application in the production process of products (such as rotor compressor) in various trades, and its performance and cost are important contents needing to be considered in the design process of permanent magnet motor. Among them, the cost of permanent magnet accounts for an important part of the cost of permanent magnet motor, and in the related art, it is difficult to accurately select the permanent magnet with appropriate size during the design and manufacture of permanent magnet motor. If the size of permanent magnet is too large, it will lead to sharp rise of motor manufacturing cost, and reduce the performance-price ratio of motor. If the size of permanent magnet is too small, it will lead to poor demagnetization resistance, affecting the performance of motor.

[0003] It can be seen that the permanent magnet motor in the related art has the technical problem of being difficult to balance performance and cost. For this technical problem, no effective solution has been proposed so far. INVENTION CONTENTS

[0004] The main purpose of the utility model is to provide a kind of permanent magnet motor and compressor, to solve the technical problem that permanent magnet motor in the related art is difficult to balance performance and cost.

[0005] In order to achieve the above purpose, according to one aspect of the utility model, a kind of permanent magnet motor is provided, comprising: rotor assembly, rotor assembly includes rotor core and multiple permanent magnet groups, each permanent magnet group includes two permanent magnets, each permanent magnet is embedded in rotor core;Stator assembly, stator assembly is arranged around rotor assembly;Wherein, the structure of permanent magnet motor satisfies 20≤S*P*R1 / R2≤29, S is the projection area of any one permanent magnet in the preset plane, the preset plane is perpendicular to the axial direction of permanent magnet motor, P is the pole pair number of rotor assembly, R1 is the inscribed circle radius of stator assembly, R2 is the circumscribed circle radius of stator assembly.

[0006] Further, the projection of each permanent magnet in the preset plane is a rectangle, the width of the rectangle is L1, the length of the rectangle is L2, L1

[0007] Further, the pole number of rotor assembly is 6, and the structure of permanent magnet motor satisfies 0.50≤L1 / P≤0.57.

[0008] Further, the pole number of rotor assembly is 8, and the structure of permanent magnet motor satisfies 0.35≤L1 / P≤0.40.

[0009] Further, the pole number of rotor assembly is 10, and the structure of permanent magnet motor satisfies 0.25≤L1 / P≤0.28.

[0010] Further, the residual magnetism induction intensity of each permanent magnet in 20 DEG C environment is 1.28T <= Br <= 1.45T.

[0011] Further, two permanent magnets belonging to the same permanent magnet group are arranged in a V shape; and / or, the stator assembly comprises a stator body and a stator winding wound on the stator body, wherein the stator winding is a concentrated winding.

[0012] According to another aspect of the utility model, a kind of compressor is provided, and the compressor includes the above permanent magnet motor, and the displacement of compressor 7.0cc <= V <=24.0cc.

[0013] Further, the structure of compressor satisfies 1.1 <= H*L1 / Vmax <=1.6, wherein H is the intrinsic coercive force of each permanent magnet of the permanent magnet motor in 20 DEG C environment, L1 is the width of the projection of each permanent magnet in a preset plane, and Vmax is the maximum value of the displacement of compressor.

[0014] Further, the refrigerant of compressor is R32 or R410A.

[0015] The permanent magnet motor of the utility model embodiment comprises: a rotor assembly, the rotor assembly comprises a rotor core and a plurality of permanent magnet groups, each permanent magnet group comprises two permanent magnets, and each permanent magnet is embedded in the rotor core; a stator assembly is arranged around the rotor assembly; wherein the structure of the permanent magnet motor satisfies 20 <= S*P*R1 / R2 <=29, S is the projection area of any one permanent magnet in a preset plane, the preset plane is perpendicular to the axial direction of the permanent magnet motor, P is the pole pair number of the rotor assembly, R1 is the inscribed circle radius of the stator assembly, and R2 is the circumscribed circle radius of the stator assembly. The utility model embodiment is designed by combining the size of the stator assembly and the pole pair number of the rotor assembly, and the size of each permanent magnet is designed specifically. Specifically, the permanent magnet is designed by combining the inscribed radius R1 of the stator assembly, the circumscribed radius R2 of the stator assembly and the pole pair number of the rotor assembly. The structure parameters of the motor satisfy 20 <= S*P*R1 / R2 <=29, so that the size of the permanent magnet is in a more suitable range, the anti-demagnetization ability is poor due to the design of the permanent magnet being too small, the performance of the motor is affected, the anti-demagnetization ability is excessive due to the design of the permanent magnet being too large, and the cost of the motor is increased. The cost and performance of the motor can be reasonably considered, and the technical problem that the permanent magnet motor is difficult to consider performance and cost in the related art is solved. BRIEF DESCRIPTION OF DRAWINGS

[0016] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the present application, and together with the description of the exemplary embodiments of the present application, serve to explain the present application. In the drawings:

[0017] Figure 1 Figure 1 is a structural schematic diagram of a rotor assembly of an embodiment of the permanent magnet motor of the utility model;

[0018] Figure 2 Figure 2 is a structural schematic diagram of an assembled stator assembly and rotor assembly of an embodiment of the permanent magnet motor of the utility model;

[0019] Figure 3 Figure 3 is a cost comparison schematic diagram of an embodiment scheme one and an original scheme of the permanent magnet motor of the utility model;

[0020] Figure 4 Figure 4 is a comparison schematic diagram of actual demagnetization currents of an embodiment scheme one and an original scheme of the permanent magnet motor of the utility model;

[0021] Figure 5 Figure 5 is a cost comparison schematic diagram of an embodiment scheme two and an original scheme of the permanent magnet motor of the utility model;

[0022] Figure 6 Figure 6 is a comparison schematic diagram of actual demagnetization currents of an embodiment scheme two and an original scheme of the permanent magnet motor of the utility model.

[0023] Among them, the above-mentioned drawings include the following figure marks:

[0024] 1, rotor assembly; 11, rotor core; 12, permanent magnet group; 121, permanent magnet; 2, stator assembly. DETAILED DESCRIPTION

[0025] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The utility model will be described in detail below with reference to the drawings and in combination with the embodiments.

[0026] Please refer to Figures 1 to 6 The embodiment of the utility model provides a kind of permanent magnet motor, comprising: rotor assembly 1, rotor assembly 1 includes rotor core 11 and multiple permanent magnet groups 12, each permanent magnet group 12 includes two permanent magnets 121, each permanent magnet 121 is embedded in rotor core 11;Stator assembly 2, stator assembly 2 is arranged around rotor assembly 1;Wherein, permanent magnet motor structure satisfies 20≤S*P*R1 / R2≤29, S is the projection area of any one permanent magnet 121 in preset plane, preset plane is perpendicular to the axial direction of permanent magnet motor, P is the pole pair number of rotor assembly 1, R1 is the incircle radius of stator assembly 2, R2 is the circumscribed circle radius of stator assembly 2.

[0027] The embodiment of the utility model discloses through the size of the stator subassembly 2 and the pole pair number of rotor subassembly 1, the size of each permanent magnet 121 is designed pertinently, specifically, the permanent magnet 121 is designed in combination with the internal switching radius R1 of stator subassembly 2, the excircle radius R2, the pole pair number of rotor subassembly 1, and the structure parameter of using this motor satisfies 20≤S*P*R1 / R2≤29, like this, can make the size of permanent magnet 121 be in more suitable range, avoid the poor anti demagnetization ability of permanent magnet 121 design too small and affect motor performance, while avoid the surplus of anti demagnetization ability of permanent magnet 121 design too big and further lead to motor cost increase, can reasonably give consideration to the cost and performance of motor, solved the technical problem of permanent magnet motor in the related art difficult to give consideration to performance and cost.

[0028] In the embodiment, the projection of each permanent magnet 121 in the preset plane is a rectangle, the width of the rectangle is L1, the length of the rectangle is L2, L1

[0029] In actual implementation, the number of permanent magnet group 12 on the rotor subassembly 1 of the permanent magnet motor can have multiple choices, that is, the pole number of the rotor subassembly 1 can be various, for different pole numbers, the applicant finds that there is great relevance between the size design of the permanent magnet 121, when the pole number changes, the size of the permanent magnet 121 of the past is often difficult to adapt to the permanent magnet motor, leading to the above-mentioned poor anti demagnetization ability of motor or excessive anti demagnetization ability, which is not conducive to the cost control and performance guarantee of the motor. Therefore, for different rotor pole number conditions, the applicant further designs the relevant structure size of the permanent magnet motor pertinently, specifically:

[0030] In an optional embodiment, the pole number of the rotor subassembly 1 is 6, and the permanent magnet motor structure satisfies 0.50≤L1 / P≤0.57.

[0031] In another optional embodiment, the pole number of the rotor subassembly 1 is 8, and the permanent magnet motor structure satisfies 0.35≤L1 / P≤0.40.

[0032] In another alternative embodiment, the number of poles of the rotor assembly 1 is 10, and the permanent magnet motor structure satisfies 0.25≤L1 / P≤0.28.

[0033] For the number of poles of the rotor assembly 1 being 6, 8, 10 as described above, the applicant controls the value of L1 / P to be within the corresponding range, so that the size of the permanent magnet 121 can be controlled within a preferable range, avoiding the permanent magnet 121 being too large or too small to adversely affect the performance or cost of the motor. Specifically, if the above ratio is too large, exceeding the corresponding upper limit, it will result in excessive use of permanent magnets 121, and thus high cost and excessive anti-demagnetization margin. If the above ratio is too small, exceeding the corresponding lower limit, it will result in insufficient use of permanent magnets 121, resulting in insufficient anti-demagnetization capability. In the prior art, the performance and / or cost performance of the permanent magnet motor are not as good as the scheme in the present embodiment.

[0034] In actual implementation, for any number of poles of the rotor assembly 1, the number of stator slots on the stator assembly 2 of the permanent magnet motor can also be different, and can be flexibly designed according to actual needs, such as 9-slot 6-pole, 9-slot 8-pole, 12-slot 8-pole, 12-slot 10-pole, 15-slot 10-pole, etc.

[0035] Specifically, the residual magnetism induction intensity of each permanent magnet 121 in a 20℃ environment is 1.28T≤Br≤1.45T. The permanent magnet 121 with the residual magnetism induction intensity range can have a good compromise effect on the performance and cost of the permanent magnet motor after the size structure design described above, for example, the permanent magnet 121 can be selected from 42SH to 55SH.

[0036] In one specific embodiment, the two permanent magnets 121 belonging to the same permanent magnet group 12 are arranged in a V shape; and / or, the stator assembly 2 includes a stator body and a stator winding wound on the stator body, wherein the stator winding is a concentrated winding.

[0037] In addition, the utility model discloses a kind of compressors, and the compressor includes the permanent magnet motor described above, and the displacement of compressor 7.0cc≤V≤24.0cc.

[0038] In the present embodiment, the compressor adopts the permanent magnet motor with the structure design described above, and the displacement of compressor is in the range of 7.0cc≤V≤24.0cc. The compressor in this displacement range can be well adapted to the permanent magnet motor with the size structure design described above, thereby ensuring the performance and control cost of the compressor.

[0039] Specifically, the structure of the compressor satisfies 1.1<=H*L1 / Vmax<=1.6, wherein H is intrinsic coercive force of each permanent magnet 121 of the permanent magnet motor in a 20 DEG C environment, L1 is width of a projection of each permanent magnet 121 in a preset plane, and Vmax is a maximum value of compressor displacement. The compressor refrigerant is R32 or R410A.

[0040] In actual implementation, the greater the compressor displacement V, the greater the torque required for operation and the greater the operating current. The greater the intrinsic coercive force H of the permanent magnet 121, the stronger the demagnetization resistance. H*L1 / Vmax being too large means that the permanent magnet 121 is too thick, the coercive force is too high, the cost is too high, or the compressor displacement can be made larger. H*L1 / Vmax being too small means that the demagnetization resistance is too low or the compressor with such a large displacement is not suitable. Therefore, by limiting the value range of H*L1 / Vmax in the embodiment, the permanent magnet motor can better adapt to the working condition of the compressor, thereby ensuring the performance of the compressor. L1 is width of a projection of each permanent magnet 121 in a preset plane, which is smaller than length of a projection of each permanent magnet 121 in the preset plane.

[0041] As shown in Figures 3 to 5 , Fig. 1 is a cost comparison diagram of the permanent magnet motor of the embodiment scheme one of the utility model and the motor of the original scheme. Figure 3 , Fig. 2 is a comparison diagram of actual demagnetization current of the permanent magnet motor of the embodiment scheme one of the utility model and the motor of the original scheme. Figure 4 , Fig. 3 is a cost comparison diagram of the permanent magnet motor of the embodiment scheme two of the utility model and the motor of the original scheme. Figure 5 , Fig. 4 is a comparison diagram of actual demagnetization current of the permanent magnet motor of the embodiment scheme two of the utility model and the motor of the original scheme. Figure 6 As can be seen from

[0042] , S*P*R1 / R2 of the embodiment scheme one of the permanent magnet motor of the utility model is 28.8, which is within the range of 20<=S*P*R1 / R2<=29, and S*P*R1 / R2 of the original scheme for comparison is 33.6, which exceeds the upper limit of the range of 20<=S*P*R1 / R2<=29. Compared with the original scheme, the motor cost of scheme one is reduced. Figure 3 As can be seen from Figure 4 , the actual demagnetization current of the motor of scheme one is 36A, and the actual demagnetization current of the motor of the original scheme for comparison is 43A, both of which exceed the required demagnetization current of 20A. That is to say, the demagnetization resistance of both is qualified. On this basis, the embodiment scheme one of the utility model has a cost advantage, thereby better balancing the performance and cost of the motor.

[0043] In addition, as can be seen from Figure 5As can be seen from the above, the S*P*R1 / R2 of the second embodiment of the permanent magnet motor is 20.1, which is within the range of 20≤S*P*R1 / R2≤29, and the S*P*R1 / R2 of the original scheme for comparison is 18.4, which exceeds the lower limit of the range of 20≤S*P*R1 / R2≤29. Compared with the original scheme, the motor cost of the second scheme is slightly higher. Figure 6 As can be seen from the above, the actual demagnetizing current of the motor of the second scheme is 25A, which exceeds the required demagnetizing current of 20A, and the anti-demagnetizing performance is qualified. The actual demagnetizing current of the motor of the original scheme for comparison is 18A, which does not reach the required demagnetizing current of 20A, and its anti-demagnetizing performance is unqualified. It can be seen that although the original scheme for comparison has a slightly lower cost, it does not meet the anti-demagnetizing requirement and cannot guarantee the performance of the motor. It can be seen that the second scheme of the embodiment of the utility model has a performance advantage, so that the performance and cost of the motor can be better balanced.

[0044] From the above description, it can be seen that the above-mentioned embodiments of the utility model realize the following technical effects:

[0045] The permanent magnet motor of the embodiment of the utility model comprises: a rotor assembly 1, the rotor assembly 1 comprises a rotor core 11 and a plurality of permanent magnet groups 12, each permanent magnet group 12 comprises two permanent magnets 121, and each permanent magnet 121 is embedded in the rotor core 11; a stator assembly 2, the stator assembly 2 is arranged around the rotor assembly 1; wherein the permanent magnet motor structure satisfies 20≤S*P*R1 / R2≤29, S is the projection area of any one permanent magnet 121 in a preset plane, the preset plane is perpendicular to the axial direction of the permanent magnet motor, P is the pole pair number of the rotor assembly 1, R1 is the inscribed circle radius of the stator assembly 2, and R2 is the circumscribed circle radius of the stator assembly 2. In the embodiment of the utility model, the size of each permanent magnet 121 is designed in a targeted manner by combining the size of the stator assembly 2 and the pole pair number of the rotor assembly 1. Specifically, the permanent magnet 121 is designed in combination with the inscribed radius R1, the circumscribed radius R2 of the stator assembly 2 and the pole pair number of the rotor assembly 1. The structure parameters of the motor meet 20≤S*P*R1 / R2≤29, so that the size of the permanent magnet 121 is within a more suitable range, avoiding poor anti-demagnetizing ability due to the permanent magnet 121 being designed too small, which affects the performance of the motor, and at the same time avoiding the anti-demagnetizing ability surplus due to the permanent magnet 121 being designed too large, which leads to an increase in the cost of the motor. The cost and performance of the motor can be reasonably balanced, and the technical problem that the permanent magnet motor in the related art is difficult to balance performance and cost is solved.

[0046] For purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "rear", "front", "vertical" and "horizontal" as can be perceived herein relative to the accompanying drawings refer to the orientation of the components being described. However, it is to be understood that the exemplary embodiments described herein can assume different alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices illustrated in the attached drawings, and described in the following specification are exemplary embodiments only and should not be typically construed as limiting the scope of the present application.

[0047] It is also important to note that the term "or" as used herein is intended to mean any possible combination of the features, steps or elements it modifies, including one as well as one or more. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0048] It is to be understood that the terminology used herein is for the purpose of describing the exemplary embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising", when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0049] The preferred embodiments of the present application have been described herein above with the intent of illustrating the principles of operation of the application by reference to one or more preferred embodiments. Any change in making materials or changes in the order of any steps are considered to be within the scope of the present application.

Claims

1. A permanent magnet electric machine characterized by, The application relates to a permanent magnet motor structure, comprising: a rotor assembly (1) comprising a rotor core (11) and a plurality of permanent magnet groups (12), each of the permanent magnet groups (12) comprising two permanent magnets (121), each of the permanent magnets (121) being embedded in the rotor core (11); a stator assembly (2) arranged around the rotor assembly (1); wherein the permanent magnet motor structure satisfies 20<=S*P*R1 / R2<=29, S is the projection area of any one of the permanent magnets (121) in a preset plane, the preset plane is perpendicular to the axial direction of the permanent magnet motor, P is the pole pair number of the rotor assembly (1), R1 is the inscribed circle radius of the stator assembly (2), and R2 is the circumscribed circle radius of the stator assembly (2).

2. The permanent magnet electric machine of claim 1, wherein, The projection of each of the permanent magnets (121) in the preset plane is a rectangle, the width of the rectangle is L1, the length of the rectangle is L2, L1 3. The permanent magnet electric machine of claim 2, wherein, The pole number of the rotor assembly (1) is 6, and the permanent magnet motor structure satisfies 0.50<=L1 / P<=0.

57.

4. The permanent magnet electric machine of claim 2, wherein, The pole number of the rotor assembly (1) is 8, and the permanent magnet motor structure satisfies 0.35<=L1 / P<=0.

40.

5. The permanent magnet electric machine of claim 2, wherein, The pole number of the rotor assembly (1) is 10, and the permanent magnet motor structure satisfies 0.25<=L1 / P<=0.

28.

6. The permanent magnet electric machine of any one of claims 1 to 5, characterized by, The residual magnetism induction intensity of each of the permanent magnets (121) in a 20 DEG C environment is 1.28T<=Br<=1.45T.

7. The permanent magnet electric machine of any one of claims 1 to 5, characterized by, The two permanent magnets (121) belonging to the same permanent magnet group (12) are arranged in a V shape; and / or, The stator assembly (2) comprises a stator body and a stator winding wound on the stator body, wherein the stator winding is a concentrated winding.

8. A compressor characterized by, The compressor comprises the permanent magnet motor in any one of claims 1 to 7, and the displacement of the compressor satisfies 7.0cc<=V<=24.0cc.

9. The compressor of claim 8, wherein, The structure of the compressor satisfies 1.1<=H*L1 / Vmax<=1. 6, wherein H is the intrinsic coercive force of each of the permanent magnets (121) of the permanent magnet motor in a 20 DEG C environment, L1 is the width of the projection of each of the permanent magnets (121) in a preset plane, and Vmax is the maximum value of the displacement of the compressor.

10. The compressor of claim 8, wherein, The refrigerant of the compressor is R32 or R410A.

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