Rotor structure, motor and compressor

Abstract

The utility model provides a rotor structure, a motor and a compressor. The rotor structure comprises a rotor iron core. The rotor core is provided with a plurality of magnetic poles, the axial surface of the rotor core is taken as a projection surface, the rotor core is provided with linear magnetic steel grooves and V-shaped magnetic steel grooves, the linear magnetic steel grooves and the V-shaped magnetic steel grooves are alternately distributed on the plurality of magnetic poles, first magnetic steel is arranged in the linear magnetic steel grooves, and second magnetic steel is arranged in the V-shaped magnetic steel grooves. According to the utility model, the linear magnetic steel grooves and the V-shaped magnetic steel grooves are alternately distributed, so that the distribution performance of the linear magnetic steel grooves can be improved, and the distribution cost of the V-shaped magnetic steel grooves can be reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of air conditioners, and in particular relates to a rotor structure, a motor and a compressor. Background Art

[0002] Permanent magnet synchronous motors have the advantages of high power factor, large starting torque, simple structure, reliable operation, and small size. Therefore, they have been widely used in various industries. The distribution type of magnetic steel on the rotor structure, the design of the magnetic isolation holes and the outer contour of the rotor have an important impact on the efficiency, demagnetization, noise and cost of the motor. The existing rotor structure magnetic steel distribution is mainly straight and V-shaped. The magnetic isolation holes and the outer contour of the rotor are designed according to different magnetic steel distributions to improve the motor's anti-demagnetization performance, improve the back electromotive force waveform, make the waveform close to sine, weaken high-order harmonics, and reduce vibration and noise during motor operation. However, the existing rotor structure straight and V-shaped magnetic steel arrangement methods have the problem that the rotor space utilization rate of the straight-line magnetic steel distribution is low, the motor efficiency is low, and the magnetic steel V-shaped distribution of the magnetic steel uses a large amount of magnetic steel, resulting in high motor cost. Utility Model Content

[0003] The utility model provides a rotor structure, a motor and a compressor, which can solve the technical problem of low space utilization rate of the magnetic steel arrangement modes of the existing rotor structure in the shape of a straight line or a shape of a V.

[0004] The utility model provides a rotor structure, which includes a rotor core;

[0005] The rotor core has a plurality of magnetic poles. Taking the axial surface of the rotor core as the projection surface, the rotor core is provided with a straight magnetic steel slot and a V-shaped magnetic steel slot, and the straight magnetic steel slot and the V-shaped magnetic steel slot are alternately distributed on the plurality of magnetic poles, respectively. The straight magnetic steel slot is provided with a first magnetic steel, and the V-shaped magnetic steel slot is provided with a second magnetic steel.

[0006] In some embodiments, in the circumferential direction of the rotor core, the opposite pole of the I-shaped magnetic steel slot of each pole is the V-shaped magnetic steel slot.

[0007] In some embodiments, the angle between adjacent q axes is the geometric angle occupied by the magnetic pole on the rotor core, the geometric angle occupied by the V-shaped magnetic steel slot on the rotor core is θ, and the geometric angle occupied by the I-shaped magnetic steel slot on the rotor core is δ;

[0008] The angle θ and the angle δ satisfy: θ=δ=π / p, where: p is the number of magnetic pole pairs.

[0009] In some embodiments, the second magnetic steel includes a first magnet and a second magnet, the width of the first magnet and the second magnet in the circumferential direction of the rotor core is d1, and the length of the first magnet and the second magnet in the circumferential direction of the rotor core is L1; the angle between the radial inner side of the first magnet and the radial inner side of the second magnet is γ, the width of the first magnetic steel in the circumferential direction of the rotor core is d2, and the length of the first magnetic steel in the circumferential direction of the rotor core is L2;

[0010] The width d2 satisfies: d2 = 1.14*d1, and the length L2 satisfies: L2 = 2.04*L1*cos(γ / 2).

[0011] In some embodiments, in the circumferential direction of the rotor core, the width between the magnetic isolation grooves of two adjacent poles is W2, and the outer circle of the rotor core corresponding to the adjacent poles is provided with a cut edge, and one of the tangents of the circle corresponding to the maximum diameter of the rotor core is parallel to the cut edge, and the width of the tangent and the cut edge in the radial direction is W1, and the width W1 and the width W2 satisfy: 1 / 2*W2<W1<W2.

[0012] In some embodiments, the outer contour line of the rotor core of each magnetic pole is symmetrically arranged about the d-axis, and the outer contour line corresponding to the V-shaped magnetic steel slot from the d-axis to the q-axis includes a first curve, a second curve and a first straight line connected in sequence, and the outer contour line corresponding to the I-shaped magnetic steel slot from the d-axis to the q-axis includes a third curve, a fourth curve and a second straight line connected in sequence.

[0013] In some embodiments, the angle between the extension line from the first end of the first curve to the center of the rotor core and the extension line from the second end of the first curve to the center of the rotor core is β, and the angle between the extension line from the first end of the fourth curve to the center of the rotor core and the extension line from the second end of the fourth curve to the center of the rotor core is α, and the angle β and the angle α satisfy: α<β<π / 3p, where: p is the number of magnetic pole pairs.

[0014] In some embodiments, the length of the first straight line in the circumferential direction of the rotor core is b2, the length of the second straight line in the circumferential direction of the rotor core is b1, and the length b1 and the length b2 satisfy: b1<b2<R*sin(π / 4p), where: R is the maximum diameter of the rotor core.

[0015] A motor comprises a rotor structure, wherein the rotor structure is the above-mentioned rotor structure.

[0016] A compressor comprises a motor, wherein the motor is the motor mentioned above.

[0017] The utility model provides a rotor structure, a motor and a compressor, which have the following beneficial effects:

[0018] The straight magnetic steel slots and V-shaped magnetic steel slots are alternately distributed on the rotor core. Compared with the conventional straight magnetic steel slots arranged radially outside the V-shaped magnetic steel slots, this embodiment adopts a straight magnetic steel slot and V-shaped magnetic steel slots alternately distributed magnetic steel, which not only improves the utilization rate of the rotor space, but also reduces the cost of the rotor motor, and achieves the goal of reducing costs and increasing efficiency of the motor. If all the magnetic steel slots adopt V-shaped magnetic steel slots, the amount of magnetic steel used is much larger than that of the straight magnetic steel slots. The second magnetic steel is rare earth magnetic steel, which is expensive, and thus greatly increases the cost of the motor; if all the magnetic steel slots adopt straight magnetic steel slots, the cost of the motor is reduced, but the performance of the motor is greatly reduced relative to the distribution of V-shaped magnetic steel slots. Therefore, this embodiment adopts the alternating distribution of straight magnetic steel slots and V-shaped magnetic steel slots, which can not only improve the distribution performance of the straight magnetic steel slots, but also reduce the cost of the V-shaped magnetic steel slot distribution. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the implementation of the utility model or the technical solution in the prior art, the following is a brief introduction to the drawings required for the implementation or the prior art description. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0020] Figure 1 A schematic diagram of a rotor structure according to an embodiment of the utility model;

[0021] Figure 2 A schematic diagram of the length and width of the first magnetic steel and the second magnetic steel according to an embodiment of the present utility model;

[0022] Figure 3 It is a schematic diagram of the first to fourth curves, the first straight line and the second straight line of an embodiment of the utility model;

[0023] Figure 4 It is a schematic diagram of the length b1, the length b2, the angle α and the angle β of an embodiment of the utility model;

[0024] Figure 5 for Figure 4 Detail enlargement in the figure.

[0025] Figures: 1-rotor core; 2-I-shaped magnetic steel slot; 21-first magnetic steel; 201-third curve; 202-fourth curve; 203-second straight line; 3-V-shaped magnetic steel slot; 31-second magnetic steel; 311-first magnet; 312-second magnet; 301-first curve; 302-second curve; 303-first straight line; 4-magnetic isolation slot; 5-cut edge; 6-circle corresponding to the maximum diameter of the rotor core. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0027] In the description of the present utility model, it needs to be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present utility model; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0028] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here 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" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0029] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0030] See also Figure 1 As shown, according to an embodiment of the utility model, a rotor structure is provided, which includes a rotor core 1; the rotor core 1 has a plurality of magnetic poles, and with the axial surface of the rotor core 1 as the projection surface, a straight-line magnetic steel slot 2 and a V-shaped magnetic steel slot 3 are provided on the rotor core 1, and the straight-line magnetic steel slot 2 and the V-shaped magnetic steel slot 3 are alternately distributed on the plurality of magnetic poles, respectively, a first magnetic steel 21 is provided in the straight-line magnetic steel slot 2, and a second magnetic steel 31 is provided in the V-shaped magnetic steel slot 3.

[0031] In this embodiment, the straight magnetic steel slots 2 and the V-shaped magnetic steel slots 3 are alternately distributed on the rotor core 1. Compared with the conventional straight magnetic steel slots 2 arranged radially outside the V-shaped magnetic steel slots 3, this embodiment adopts the alternating magnetic steel distribution method of the straight magnetic steel slots 2 and the V-shaped magnetic steel slots 3, which not only improves the utilization rate of the rotor space, but also reduces the cost of the rotor motor, and achieves the goal of reducing costs and increasing efficiency of the motor. If all the magnetic steel slots adopt the V-shaped magnetic steel slots 3, the amount of magnetic steel used is much greater than the straight magnetic steel slots 2, and the second magnetic steel 31 is a rare earth magnetic steel, which is expensive, thus greatly increasing the cost of the motor; if all the magnetic steel slots adopt the straight magnetic steel slots 2 distribution, the cost of the motor is reduced, but the performance of the motor is greatly reduced relative to the distribution method of the V-shaped magnetic steel slots 3. Therefore, this embodiment adopts the alternating distribution of the straight magnetic steel slots 2 and the V-shaped magnetic steel slots 3, which can not only improve the distribution performance of the straight magnetic steel slots 2, but also reduce the cost of the distribution of the V-shaped magnetic steel slots 3.

[0032] As a specific implementation method, the I-shaped magnetic steel groove 2 and the V-shaped magnetic steel groove 3 both include a magnetic steel mounting groove and a magnetic isolation groove 4. The sizes of the first magnetic steel 21 and the second magnetic steel 31 correspond to the corresponding magnetic steel mounting grooves, respectively. The first magnetic steel 21 and the second magnetic steel 31 are respectively installed in the magnetic steel mounting grooves. The magnetic isolation groove 4 plays a role of magnetic isolation to prevent magnetic leakage at the end of the magnetic steel, so as to improve the anti-demagnetization ability of the end of the magnetic steel.

[0033] See also Figures 1 to 3 As shown, in the circumferential direction of the rotor core 1 , the opposite pole of each pole of the I-shaped magnetic steel slot 2 is a V-shaped magnetic steel slot 3 .

[0034] In this embodiment, the opposite poles of the rotor core 1 use magnetic steel slots of different shapes. This is because if all the magnetic steel slots use V-shaped magnetic steel slots 3, the amount of magnetic steel used is much greater than that of the straight magnetic steel slots 2. The second magnetic steel 31 is a rare earth magnetic steel, which is expensive, thus greatly increasing the cost of the motor; if all the magnetic steel slots use straight magnetic steel slots 2, the cost of the motor is reduced, but the performance of the motor is greatly reduced compared to the distribution of V-shaped magnetic steel slots 3. Therefore, this embodiment uses the alternating distribution of straight magnetic steel slots 2 and V-shaped magnetic steel slots 3, and only one type of magnetic steel slot is set at each pole, which can not only improve the distribution performance of the straight magnetic steel slots 2, but also reduce the cost of the distribution of the V-shaped magnetic steel slots 3.

[0035] It is worth noting that the number of poles of the motor is the number of magnetic poles of the motor. The magnetic poles are divided into N poles and S poles. Generally, the number of magnetic poles appears in pairs. The pair of poles in this embodiment refers to the V-shaped magnetic steel slot 3 opposite to the I-shaped magnetic steel slot 2 of each pole.

[0036] See also Figure 2 and Figure 4 As shown, the rotor core 1 is formed by stacking silicon steel sheets of the same thickness, the angle between adjacent q axes is the geometric angle occupied by the magnetic poles on the rotor core 1, the geometric angle occupied by the V-shaped magnetic steel slot 3 on the rotor core 1 is θ, and the geometric angle occupied by the I-shaped magnetic steel slot 2 on the rotor core 1 is δ. In order to ensure that the peak magnetic density generated by different poles in the air gap is equal, the distribution of each magnetic pole on the rotor core 1 satisfies that the angle θ and the angle δ satisfy: θ=δ=π / p, where: p is the number of magnetic pole pairs.

[0037] See also Figure 2 and Figure 4 As shown, the second magnetic steel 31 includes a first magnet 311 and a second magnet 312, the width of the first magnet 311 and the second magnet 312 in the circumferential direction of the rotor core 1 is d1, and the length of the first magnet 311 and the second magnet 312 in the circumferential direction of the rotor core 1 is L1; the angle between the radial inner edge of the first magnet 311 and the radial inner edge of the second magnet 312 is γ, the width of the first magnetic steel 21 in the circumferential direction of the rotor core 1 is d2, and the length of the first magnetic steel 21 in the circumferential direction of the rotor core 1 is L2; ​​the width d2 satisfies: d2=1.14*d1, and the length L2 satisfies: L2=2.04*L1*cos(γ / 2).

[0038] In this embodiment, since the rotor core 1 adopts an arrangement in which two magnetic steel slot shapes are alternately arranged, in order to ensure that the air gap magnetic density and back electromotive force waveforms are sinusoidal and the air gap magnetic field intensity peaks are the same, the geometric angles occupied by the two magnetic steel slots on the rotor core 1 and the lengths and widths of the first magnetic steel 21 and the second magnetic steel 31 in the circumferential direction of the rotor core 1 are respectively limited, which is different from the rotor structure with the same magnetic steel slot shape.

[0039] See also Figure 3 and Figure 4 As shown, the outer contour line of the rotor core 1 of each magnetic pole is symmetrically arranged about the d-axis, the outer contour line corresponding to the V-shaped magnetic steel slot 3 from the d-axis to the q-axis includes a first curve 301, a second curve 302 and a first straight line 303 connected in sequence, and the outer contour line corresponding to the I-shaped magnetic steel slot 2 from the d-axis to the q-axis includes a third curve 201, a fourth curve 202 and a second straight line 203 connected in sequence.

[0040] In this embodiment, since the I-shaped magnetic steel slots 2 and the V-shaped magnetic steel slots 3 are alternately distributed on the rotor core 1, the air gap magnetic flux density and the sine waveform of the back electromotive force, and the peak value of the air gap magnetic field intensity will change accordingly after the magnetic steel is installed with different magnetic steel slot shapes. Based on the arrangement of the magnetic steel slots, this embodiment connects the conventional contour line of the rotor core 1 from the d-axis to the q-axis with an arc line, and arranges it to be connected by two curves and a straight line, so as to ensure that the peak value of the air gap magnetic field intensity is equal, the air gap magnetic flux density and the sine waveform of the back electromotive force are sinusoidal, and the purpose of reducing the motor torque pulsation, weakening high-order harmonics, and reducing the motor vibration and noise is achieved.

[0041] See also Figure 3 and Figure 4 As shown, the angle between the extension line from the first end of the first curve 301 to the center of the rotor core 1 and the extension line from the second end of the first curve 301 to the center of the rotor core 1 is β, that is, the center angle to the center of the rotor core 1 corresponding to the first curve 301; the angle between the extension line from the first end of the fourth curve 202 to the center of the rotor core 1 and the extension line from the second end of the fourth curve 202 to the center of the rotor core 1 is α, that is, the center angle to the center of the rotor core 1 corresponding to the fourth curve 202, and the angle β and the angle α satisfy: α<β<π / 3p, where: p is the number of magnetic pole pairs.

[0042] Specifically, α<β is because the magnetic density formed in the air gap by the magnetic pole corresponding to the V-shaped magnetic steel slot 3 is different from that of the straight-line magnetic steel slot 2, wherein the magnetic density of the V-shaped magnetic steel slot 3 is relatively concentrated. Therefore, α<β, β<π / 3p is to leave design space for other curves and straight lines on the outer contour.

[0043] See also Figure 3 and Figure 4 As shown, the length of the first straight line 303 in the circumferential direction of the rotor core 1 is b2, and the length of the second straight line 203 in the circumferential direction of the rotor core 1 is b1. The length b1 and the length b2 satisfy: b1<b2<R*sin(π / 4p), where: R is the maximum diameter of the rotor core 1.

[0044] Specifically, b1<b2 is because the magnetic flux density formed in the air gap by the magnetic pole corresponding to the V-shaped magnetic steel slot 3 is different from that of the straight magnetic steel slot 2, wherein the magnetic flux density of the V-shaped magnetic steel slot 3 is relatively concentrated, and b1<b2 is used to solve the problem of excessive concentration of the magnetic flux density corresponding to the V-shaped magnetic steel slot 3; in order to reduce the torque pulsation of the motor, the magnetic pole corresponding to the V-shaped magnetic steel slot 3 and the magnetic pole corresponding to the straight magnetic steel slot 2 occupy the same degree of the rotor center angle, that is, π / p, then the angle occupied by a single permanent magnet of the magnetic pole corresponding to the V-shaped magnetic steel slot 3 is π / 2p, and b2<R*sin(π / 4p) is because the maximum angle of the rotor center angle occupied by the straight line segment is π / 4p. Taking b2 as an example, if the maximum center angle ω occupied by b2 is π / 4p, according to the trigonometric function, b2<R*sin(π / 4p), then it can be deduced that b1<b2<R*sin(π / 4p).

[0045] It is worth noting that, in this embodiment, since the rotor core 1 adopts an arrangement method in which two magnetic steel slot shapes are alternately arranged, in order to ensure that the air gap magnetic flux density and the back electromotive force waveform are sinusoidal and the peak value of the air gap magnetic field intensity is the same, the setting of the rotor outer contour, such as the length of the first straight line 303 and the second straight line 203, the corresponding angles of the second curve 302 and the fourth curve 202 on the rotor core 1, and the length and width of the first magnetic steel 21 and the second magnetic steel 31 in the circumferential direction of the rotor core 1 are different from the rotor structure with the same magnetic steel slot shape. In this embodiment, by setting the magnetic steel thickness, the length, angle, position of the curve, and the length and position of the straight line, it is achieved that the peak value of the air gap magnetic field intensity is equal, the air gap magnetic flux density and the back electromotive force waveform are sinusoidal, and the purpose of reducing the motor torque pulsation, weakening the high-order harmonics, and reducing the motor vibration and noise is achieved.

[0046] As a specific implementation method, in this embodiment, only the angle between the first curve 301 and the fourth curve 202, and the length of the first straight line 303 and the second straight line 203 are limited. Taking the outer contour line corresponding to the I-shaped magnetic steel slot 2 from the d-axis to the q-axis as an example, when the angle of the fourth curve 202 is determined, although only the length of the second straight line 203 is limited, by limiting the length of the second straight line 203, the angle between the second straight line 203 and the center of the rotor core 1 is also determined. In order to reserve a certain adjustment value, in this embodiment, the angle between the third curve 201 and the center of the rotor core 1 is not set, but is flexibly adjusted according to the angle of the fourth curve 202 and the length of the second straight line 203. Similarly, the angle between the first curve 301 and the center of the rotor core 1 is not limited.

[0047] See also Figure 5As shown, in the circumferential direction of the rotor core 1, the width between the magnetic isolation slots 4 of two adjacent poles is W2, and a cut edge 5 is provided on the outer circle of the rotor core 1 corresponding to the adjacent positions of the two poles, and one of the tangents of the circle 6 corresponding to the maximum diameter of the rotor core 1 is parallel to the cut edge 5, and the width of the tangent and the cut edge 5 in the radial direction is W1, and the width W1 and the width W2 satisfy: 1 / 2*W2<W1<W2.

[0048] Specifically, the width W1 is designed to improve the sinusoidality of the air gap magnetic flux waveform, weaken high-order harmonics, and reduce electromagnetic noise; this embodiment uses width W2 to limit width W1 because in the process of rotor structure design, in order to prevent permanent magnet end leakage from causing motor performance degradation, the width of the magnetic isolation bridge width W2 is generally minimized. Limiting width W1 in this way can avoid the reduction of rotor cross-sectional area caused by optimizing the air gap magnetic flux waveform, resulting in a reduction in permanent magnet length and motor performance degradation. After the limitation, the limited space of the rotor can be used as much as possible. Based on this as a starting point, other dimensions of the rotor outer contour are designed to achieve the purpose of optimizing the air gap magnetic flux waveform and improving motor performance. Therefore, there are different methods for setting the motor rotor structure to optimize the air gap magnetic flux waveform. Different optimization directions for design schemes will result in different solution results. The method is not unique and can be flexibly selected according to different schemes.

[0049] In this embodiment, since the direction of optimizing the air gap flux density waveform is different and the structure of the rotor is also different, a cut edge 5 is provided, and the radial vertical distance from the cut edge 5 to the center of the rotor core 1 is reduced, so that the contour between adjacent poles is recessed toward the rotor core 1, so as to optimize the waveform, and the magnetic steel space is compressed, thereby improving the sinusoidality of the motor air gap flux density and back electromotive force waveform, weakening high-order harmonics, and reducing the vibration and noise of the motor.

[0050] It is worth noting that the setting of the outer circular cutting edge 5 in this embodiment is a common technical means. The design of the outer circular cutting edge 5 of various rotor structures is relatively conventional, but the length, angle, position, number, etc. of the outer circular cutting edge 5 are different due to the different structures of each rotor structure. If only the outer circular cutting edge 5 is set, it is generally difficult to achieve the ideal effect of waveform sine. Therefore, it is necessary to make corresponding restrictions on the center angle angle, curvature radius, center position of the curve and different curves of the outer contour of the rotor core 1 to achieve the purpose of waveform sine. In this embodiment, since the rotor core 1 adopts two magnetic steel slot shapes, in order to ensure that the air gap magnetic flux and back electromotive force waveform sine and the peak value of the air gap magnetic field intensity are the same, the setting of the rotor outer contour, such as the length of the first straight line 303 and the second straight line 203, the corresponding angles of the second curve 302 and the fourth curve 202 on the rotor core 1, and the length and width of the first magnetic steel 21 and the second magnetic steel 31 in the circumferential direction of the rotor core 1 are different from the rotor structure with the same magnetic steel slot shape. This embodiment achieves the purpose of reducing the motor torque pulsation, weakening high-order harmonics, and reducing the motor vibration and noise by setting the magnetic steel thickness, the length, angle, and position of the curve, and the length and position of the straight line to ensure that the peak values ​​of the air gap magnetic field intensity are equal, and the air gap magnetic density and back electromotive force waveforms are sinusoidal.

[0051] A motor comprises a rotor structure, wherein the rotor structure is the above-mentioned rotor structure.

[0052] The electromagnetic noise of permanent magnet synchronous motors mainly comes from high-order harmonics generated during the operation of the motor. Harmonics are generated because the sinusoidality of the air gap magnetic density and back electromotive force waveforms is low, resulting in a large proportion of harmonics and a high distortion rate. The motor generates torque pulsation, forming vibration and noise.

[0053] Based on the above principle, the motor of this embodiment realizes the unevenness of the air gap magnetic density of the motor by designing a rotor structure, improves the sinusoidality of the air gap magnetic density and the back electromotive force waveform, and reduces the electromagnetic noise. A rotor structure with alternating distribution of "I" shape and "V" shape is proposed, which realizes the increase of the air gap magnetic density of the motor and improves the motor efficiency, while reducing the amount of magnetic steel used and reducing the cost of the motor. In addition, by setting the width and length of the magnetic steel of each pole of the rotor core 1 and the curvature, angle and length of the rotor contour line of each pole, the sinusoidality of the air gap magnetic density of the rotor structure in this embodiment is improved, the high-order harmonics in the operation process of the motor are weakened, and the electromagnetic noise is reduced, so as to achieve the purpose of reducing cost, increasing efficiency, reducing vibration and reducing noise of the motor.

[0054] A compressor comprises a motor, which is the motor mentioned above.

[0055] In the compressor motor, the rotor structure of the motor affects the performance, noise, reliability and cost of the motor. Among them, reducing the noise of the motor and thus reducing the noise of the compressor is one of the important concerns to improve the user experience. As for weakening the electromagnetic noise of the motor, the arrangement of magnetic steel in the motor rotor structure, the shape of the rotor, and the design of the magnetic isolation holes are one of the important means to weaken the electromagnetic noise. Therefore, the design and optimization of the motor rotor structure to reduce the electromagnetic noise of the motor is an important part of the motor design.

[0056] In this embodiment, the straight magnetic steel slots 2 and the V-shaped magnetic steel slots 3 are alternately distributed on the rotor core 1. Compared with the conventional straight magnetic steel slots 2 arranged radially outside the V-shaped magnetic steel slots 3, this embodiment adopts the alternating magnetic steel distribution method of the straight magnetic steel slots 2 and the V-shaped magnetic steel slots 3, which not only improves the utilization rate of the rotor space, but also reduces the cost of the rotor motor, and achieves the goal of reducing costs and increasing efficiency of the motor. If all the magnetic steel slots adopt the V-shaped magnetic steel slots 3, the amount of magnetic steel used is much greater than the straight magnetic steel slots 2, and the second magnetic steel 31 is a rare earth magnetic steel, which is expensive, thus greatly increasing the cost of the motor; if all the magnetic steel slots adopt the straight magnetic steel slots 2 distribution, the cost of the motor is reduced, but the performance of the motor is greatly reduced relative to the distribution method of the V-shaped magnetic steel slots 3. Therefore, this embodiment adopts the alternating distribution of the straight magnetic steel slots 2 and the V-shaped magnetic steel slots 3, which can not only improve the distribution performance of the straight magnetic steel slots 2, but also reduce the cost of the distribution of the V-shaped magnetic steel slots 3.

[0057] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0058] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred implementations of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention, and these improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A rotor structure, characterized in that: include: A rotor core (1); The rotor core (1) has a plurality of magnetic poles. With the axial surface of the rotor core (1) as a projection surface, the rotor core (1) is provided with a straight-line magnetic steel slot (2) and a V-shaped magnetic steel slot (3), and the straight-line magnetic steel slot (2) and the V-shaped magnetic steel slot (3) are respectively alternately distributed on the plurality of magnetic poles. The straight-line magnetic steel slot (2) is provided with a first magnetic steel (21), and the V-shaped magnetic steel slot (3) is provided with a second magnetic steel (31).

2. The rotor structure according to claim 1, characterized in that: In the circumferential direction of the rotor core (1), the counter pole of the I-shaped magnetic steel slot (2) of each pole is the V-shaped magnetic steel slot (3).

3. The rotor structure according to claim 2, characterized in that: The angle between adjacent q axes is the geometric angle occupied by the magnetic pole on the rotor core (1), the geometric angle occupied by the V-shaped magnetic steel slot (3) on the rotor core (1) is θ, and the geometric angle occupied by the I-shaped magnetic steel slot (2) on the rotor core (1) is δ; The angle θ and the angle δ satisfy: θ=δ=π / p, where: p is the number of magnetic pole pairs.

4. The rotor structure according to claim 3, characterized in that: The second magnetic steel (31) comprises a first magnet (311) and a second magnet (312); the width of the first magnet (311) and the second magnet (312) in the circumferential direction of the rotor core (1) is d1, and the length of the first magnet (311) and the second magnet (312) in the circumferential direction of the rotor core (1) is L1; the angle between the radial inner side edge of the first magnet (311) and the radial inner side edge of the second magnet (312) is γ, the width of the first magnetic steel (21) in the circumferential direction of the rotor core (1) is d2, and the length of the first magnetic steel (21) in the circumferential direction of the rotor core (1) is L2; The width d2 satisfies: d2 = 1.14*d1, and the length L2 satisfies: L2 = 2.04*L1*cos(γ / 2).

5. The rotor structure according to claim 1, characterized in that: In the circumferential direction of the rotor core (1), the width between the magnetic isolation grooves of two adjacent poles is W2, and the outer circle of the rotor core (1) corresponding to the adjacent positions of the two poles is provided with a cut edge (5), one of the tangents of the circle (6) corresponding to the maximum diameter of the rotor core (1) is parallel to the cut edge (5), and the width of the tangent and the cut edge (5) in the radial direction is W1, and the width W1 and the width W2 satisfy: 1 / 2*W2<W1<W2.

6. The rotor structure according to any one of claims 1 to 5, characterized in that: The outer contour line of the rotor core (1) of each magnetic pole is symmetrically arranged about the d-axis, the outer contour line corresponding to the V-shaped magnetic steel slot (3) from the d-axis to the q-axis includes a first curve (301), a second curve (302) and a first straight line (303) connected in sequence, and the outer contour line corresponding to the I-shaped magnetic steel slot (2) from the d-axis to the q-axis includes a third curve (201), a fourth curve (202) and a second straight line (203) connected in sequence.

7. The rotor structure according to claim 6, characterized in that: The angle between the extension line from the first end of the first curve (301) to the center of the rotor core (1) and the extension line from the second end of the first curve (301) to the center of the rotor core (1) is β, and the angle between the extension line from the first end of the fourth curve (202) to the center of the rotor core (1) and the extension line from the second end of the fourth curve (202) to the center of the rotor core (1) is α, and the angle β and the angle α satisfy: α<β<π / 3p, where: p is the number of magnetic pole pairs.

8. The rotor structure according to claim 7, characterized in that: The length of the first straight line (303) in the circumferential direction of the rotor core (1) is b2, and the length of the second straight line (203) in the circumferential direction of the rotor core (1) is b1. The length b1 and the length b2 satisfy: b1<b2<R*sin(π / 4p), where: R is the maximum diameter of the rotor core (1).

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

10. A compressor, comprising a motor, characterized in that: The motor is the motor according to claim 9.

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