Permanent magnet synchronous motor

Abstract

The permanent magnet synchronous motor comprises rotor back iron and a magnetic steel array assembly, and the magnetic steel array assembly is arranged on the inner circumferential surface of the rotor back iron and is of a continuous structure extending in the circumferential direction of the rotor back iron; the magnetic steel array assembly comprises a plurality of magnetic steel groups which are sequentially connected along the circumferential direction of the rotor back iron; gaps are formed between the head and the tail of the magnetic steel array assembly in the circumferential direction of the rotor back iron. According to the permanent magnet synchronous motor provided by the embodiment of the invention, the gaps are formed between the head and the tail of the magnetic steel array assembly in the circumferential direction of the rotor back iron, so that the magnetic steel groups in the magnetic steel array assembly are staggered in the circumferential direction, the torque generated by the magnetic steel groups is staggered, the arrangement of the magnetic steel groups is optimized, the distribution of magnetic circuits is changed, and the stability of the motor is improved. Therefore, the torque fluctuation and vibration of the motor can be reduced, so that the motor is low in operation noise, good in energy-saving effect and high in control precision, and the motor can be widely applied to occasions needing high-precision control.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular to permanent magnet synchronous motors. Background Art

[0002] Permanent magnet synchronous motors (PMSMs) are widely used in industrial automation, electric vehicles, aerospace and other fields due to their high efficiency and high power density. However, for permanent magnet synchronous motors with high pole numbers and Halbach magnet arrays, they have higher cogging torque. When the cogging torque is large, it will cause torque fluctuations and vibrations, resulting in high noise and low control accuracy of the motor, making it difficult to use in high-precision control situations. Summary of the invention

[0003] Based on this, it is necessary to provide a permanent magnet synchronous motor to address the problem that some existing permanent magnet synchronous motors have large cogging torque, which leads to high noise during motor operation and low control accuracy.

[0004] A permanent magnet synchronous motor, comprising a rotor back iron and a magnetic steel array assembly; the magnetic steel array assembly is arranged on the inner circumferential surface of the rotor back iron and is constructed as a continuous structure extending along the circumferential direction of the rotor back iron; the magnetic steel array assembly comprises a plurality of magnetic steel groups sequentially connected along the circumferential direction of the rotor back iron;

[0005] Wherein, along the circumferential direction of the rotor back iron, there is a gap between the head and the tail of the magnetic steel array assembly.

[0006] In some embodiments, the central axes of the two groups of magnetic steel groups arranged opposite to each other in the radial direction of the rotor back iron are arranged at an angle.

[0007] In some embodiments, each of the magnetic steel groups includes a first magnetic steel, a second magnetic steel, a third magnetic steel and a fourth magnetic steel which are arranged in sequence;

[0008] The magnetization directions of the first magnetic steel, the second magnetic steel, the third magnetic steel and the fourth magnetic steel are all different.

[0009] In some embodiments, the first magnetic steel and the third magnetic steel have opposite magnetization directions;

[0010] The second magnetic steel and the fourth magnetic steel have opposite magnetization directions.

[0011] In some embodiments, the first magnetic steel and the third magnetic steel are radial magnetic steels;

[0012] The second magnetic steel and the fourth magnetic steel are tangential magnetic steels.

[0013] In some embodiments, the central angle θ1 of the first magnetic steel satisfies the condition:

[0014] θ1= ;

[0015] Among them, s satisfies the conditions:

[0016] s=6p;

[0017] p is the number of the magnetic steel groups, and p is a positive even number greater than or equal to 2.

[0018] In some embodiments, the central angle θ2 of the third magnetic steel is the same as the central angle θ1 of the first magnetic steel.

[0019] In some embodiments, the central angle θ3 of the second magnetic steel satisfies the condition:

[0020] θ3= ;

[0021] Among them, s satisfies the conditions:

[0022] s=6p;

[0023] p is the number of the magnetic steel groups, and p is a positive even number greater than or equal to 2.

[0024] In some embodiments, the central angle θ4 of the fourth magnetic steel is the same as the central angle θ3 of the second magnetic steel.

[0025] In some embodiments, the magnetic steel group is a fan-ring structure.

[0026] In some of the embodiments, the magnetic steel array assembly is a fan-ring structure.

[0027] In some embodiments, the central angle θ5 of the magnetic steel array assembly satisfies the condition:

[0028] θ5= ;

[0029] Among them, s satisfies the conditions:

[0030] s=6p;

[0031] p is the number of the magnetic steel groups, and p is a positive even number greater than or equal to 2.

[0032] In some of the embodiments, along the radial direction of the rotor back iron, the magnetic steel array assembly has a gradually decreasing size structure design on the side of the inner circumference facing away from the rotor back iron.

[0033] In some of these embodiments, the permanent magnet synchronous motor further includes a mounting assembly;

[0034] The mounting assembly is configured with a snap-in slot;

[0035] The rotor back iron and the magnetic steel array assembly are clamped in the clamping groove.

[0036] In some embodiments, the mounting assembly includes:

[0037] The rotor housing is configured with a first accommodating cavity, wherein the first accommodating cavity has a first opening along the radial direction of the rotor back iron and a second opening along the axial direction of the rotor back iron; the first opening is connected to the second opening;

[0038] an end plate, mounted at the second opening of the rotor housing, the end plate being configured with a second accommodating cavity, the second accommodating cavity having a third opening along the axial direction of the rotor back iron; the third opening being arranged opposite to the second opening;

[0039] The second accommodating cavity and the first accommodating cavity are jointly arranged to form the clamping groove.

[0040] In some embodiments, the cavity wall of the first accommodating cavity extending radially along the rotor back iron and away from the end plate includes:

[0041] A first side wall, parallel to the radial direction of the rotor back iron;

[0042] A second side wall connected to the first side wall and located on a side close to the first opening; an end of the second side wall away from the first side wall extends obliquely toward a side close to the end plate;

[0043] One of the side walls of the rotor back iron along the axial direction thereof is in contact with the first side wall;

[0044] One of the side walls of the magnetic steel array assembly along the axial direction of the rotor back iron is in contact with the second side wall.

[0045] In some embodiments, the cavity wall of the second accommodating cavity extending radially along the rotor back iron and away from one side of the rotor housing includes:

[0046] a third side wall parallel to the radial direction of the rotor back iron;

[0047] a fourth side wall connected to the third side wall and located on a side close to the first opening; an end of the fourth side wall away from the third side wall extends obliquely toward a side close to the rotor housing;

[0048] Another side wall of the rotor back iron along the axial direction thereof is in contact with the third side wall;

[0049] Another side wall of the magnetic steel array assembly along the axial direction of the rotor back iron is in contact with the fourth side wall.

[0050] In some of the embodiments, the permanent magnet synchronous motor further includes a filling piece;

[0051] The filling piece is connected to the opposite ends of the magnetic steel array assembly.

[0052] In some embodiments, the filler is a soft magnetic filler.

[0053] In some embodiments, the center angle θ6 of the filler meets the condition:

[0054] θ6= ;

[0055] Among them, s satisfies the conditions:

[0056] s=6p;

[0057] p is the number of the magnetic steel groups, and p is a positive even number greater than or equal to 2.

[0058] The permanent magnet synchronous motor provided in the embodiment of the present application has a magnetic steel array assembly including multiple groups of magnetic steel groups connected in sequence along the circumference of the rotor back iron, and a gap is provided at the head and tail of the magnetic steel array assembly along the circumference of the rotor back iron, so that the magnetic steel groups in the magnetic steel array assembly are misaligned along the circumference, and the torque generated by the magnetic steel groups is also misaligned, thereby optimizing the arrangement of the magnetic steel groups, changing the distribution of the magnetic circuit, and thereby greatly reducing the cogging torque while maintaining the output torque performance. In this way, the torque fluctuation and vibration of the motor can be reduced, the motor operation noise is smaller, the energy-saving effect is better, the control accuracy is also higher, and it can be widely used in occasions requiring high-precision control, ultimately making the use scenarios of the permanent magnet synchronous motor more extensive. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A schematic diagram of the connection between the rotor back iron and the magnetic steel array assembly in a permanent magnet synchronous motor provided in some embodiments of the present application.

[0060] Figure 2 Schematic diagram of the connection between the rotor back iron and the magnetic steel array assembly in a permanent magnet synchronous motor provided in other embodiments of the present application.

[0061] Figure 3 for Figure 1 Schematic diagram of the magnetic steel array assembly shown.

[0062] Figure 4 for Figure 1 A cross-sectional view at AA is shown.

[0063] Figure 5 for Figure 4 A cross-sectional view showing the rotor back iron and magnetic steel array assembly mounted on a mounting assembly.

[0064] Figure 6 for Figure 5 Schematic diagram of the installation components shown.

[0065] Figure 7 for Figure 6 Schematic diagram of the rotor housing is shown.

[0066] Figure 8 for Figure 6 Schematic diagram of the end plate shown.

[0067] Figure markings: 100-rotor back iron; 200-magnet array assembly; 210-magnet group; 211-first magnet; 212-second magnet; 213-third magnet; 214-fourth magnet; 220-fifth side wall; 230-sixth side wall; 300-installation assembly; 310-clamping groove; 320-rotor housing; 321-first accommodating cavity; 3211-first opening; 3212-second opening; 3213-first side wall; 3214-second side wall; 330-end plate; 331-second accommodating cavity; 3311-third opening; 3312-third side wall; 3313-fourth side wall; 400-filling piece; p1-first central axis; p2-second central axis. DETAILED DESCRIPTION

[0068] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0069] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0070] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0071] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0072] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0073] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0074] See also Figure 1-Figure 3 , Figure 1 A schematic diagram showing the connection between the rotor back iron 100 and the magnetic steel array assembly 200 in the permanent magnet synchronous motor provided in some embodiments of the present application is shown. Figure 2 A schematic diagram showing the connection between the rotor back iron 100 and the magnetic steel array assembly 200 in the permanent magnet synchronous motor provided in some other embodiments of the present application is shown. Figure 3 Shows Figure 1 A schematic diagram of a magnetic steel array assembly 200 is shown.

[0075] A permanent magnet synchronous motor provided in one embodiment of the present application includes a rotor back iron 100 and a magnetic steel array assembly 200. The magnetic steel array assembly 200 is arranged on the inner circumferential surface of the rotor back iron 100 and is constructed as a continuous structure extending along the circumferential direction of the rotor back iron 100. The magnetic steel array assembly 200 includes a plurality of magnetic steel groups 210 connected in sequence along the circumferential direction of the rotor back iron 100. The magnetic steel array assembly 200 has a gap between the head and the tail along the circumferential direction of the inner circumferential surface of the rotor back iron 100.

[0076] The permanent magnet synchronous motor provided in the embodiment of the present application has a magnetic steel array assembly 200 including multiple groups of magnetic steel groups 210 connected in sequence along the circumference of the rotor back iron, and a gap is provided at the head and tail of the magnetic steel array assembly 200 along the circumference of the rotor back iron 100, so that the magnetic steel groups 210 in the magnetic steel array assembly 200 are misaligned along the circumference, and the torque generated by the magnetic steel groups 210 is also misaligned, thereby optimizing the arrangement of the magnetic steel groups 210, changing the distribution of the magnetic circuit, and thus greatly reducing the cogging torque while maintaining the output torque performance. In this way, the torque fluctuation and vibration of the motor can be reduced, the noise of the motor operation is smaller, the energy-saving effect is better, the control accuracy is also higher, and it can be widely used in occasions requiring high-precision control, and ultimately the application scenarios of the permanent magnet synchronous motor are also more extensive.

[0077] It should be noted that the magnetic steel array assembly 200 of the traditional permanent magnet synchronous motor is connected end to end, or the entire magnetic steel array assembly 200 is evenly distributed, so the motor can be equally divided into a plurality of regions along the circumference of the rotor back iron 100, which is the same as the number of magnetic steel groups 210, and each magnetic steel group 210 is arranged at the center of the region. However, in the present application, since there is a gap between the head and the tail of the magnetic steel array assembly 200, each magnetic steel group 210 is misaligned compared to the position of the magnetic steel group 200 arranged in the traditional way, and this position misalignment will cause the waveform of the cogging torque to be phase misaligned, and these phase misalignments will eliminate the main order of cogging torque after superposition, thereby ultimately greatly reducing the cogging torque of the entire permanent magnet synchronous motor.

[0078] In one specific embodiment, the rotor back iron 100 serves as a supporting structure of the magnetic steel array assembly 200, and the magnetic steel array assembly 200 is bonded and fixed to the inner circumference of the rotor back iron 100, so that the fixing of the magnetic steel array assembly 200 and the rotor back iron 100 is simpler and more convenient, and the fixing method of the magnetic steel array assembly 200 and the rotor back iron 100 is optimized, which not only ensures the stability and precise position of the connection between the two, but also enhances the stability and safety of the permanent magnet synchronous motor in high-speed operation. Of course, in other embodiments, the magnetic steel array assembly 200 can also be clamped or welded to the inner circumference of the rotor back iron 100, and there is no special limitation on this.

[0079] The following is a detailed description of the structure of the permanent magnet synchronous motor. Figure 4-Figure 8 , Figure 4 Shows Figure 1 A cross-sectional view at AA is shown. Figure 5 Shows Figure 4 The cross-sectional view shows the rotor back iron 100 and the magnetic steel array assembly 200 being mounted on the mounting assembly 300 . Figure 6 Shows Figure 5 A schematic diagram of a mounting assembly 300 is shown. Figure 7 Shows Figure 6 A schematic diagram of a rotor housing 320 is shown. Figure 8 Shows Figure 6 A schematic diagram of the end plate 330 is shown.

[0080] See also Figure 1-Figure 3 In some embodiments, the central axes of the two sets of magnetic steel groups 210 arranged opposite to each other along the radial direction of the rotor back iron 100 are arranged at an angle. Figure 1-Figure 3 As shown, the central axis of one group of magnetic steel groups 210 is the first central axis p1, and the central axis of the magnetic steel group 210 arranged radially opposite to the group of magnetic steel groups 210 is the second central axis p2. Since the first central axis p1 and the second central axis p2 are arranged at an angle, it means that one of the two groups of magnetic steel groups 210 arranged radially opposite to each other is staggered along the circumferential direction of the rotor back iron 100 with the other group of magnetic steel groups 210. The two are not a symmetrical structural design, so that the torque generated by the magnetic steel group 210 can also be staggered, thereby optimizing the arrangement of the magnetic steel group 210, changing the distribution of the magnetic circuit, and then greatly reducing the cogging torque. In this way, the torque fluctuation and vibration of the motor can be reduced, so that the noise of the motor operation is smaller and the control accuracy is also higher.

[0081] See also Figure 1-Figure 3 In some of the embodiments, any two adjacent magnetic steel groups 210 fit closely to each other, so that there is no gap between adjacent magnetic steel groups 210 in the entire magnetic steel array assembly 200, which is beneficial to the uniformity of the magnetic field.

[0082] See also Figure 1-Figure 3 In some embodiments, each magnetic steel group 210 includes a first magnetic steel 211, a second magnetic steel 212, a third magnetic steel 213 and a fourth magnetic steel 214 arranged in sequence; the magnetization directions of the first magnetic steel 211, the second magnetic steel 212, the third magnetic steel 213 and the fourth magnetic steel 214 are different.

[0083] The magnetizing directions of the first magnetic steel 211, the second magnetic steel 212, the third magnetic steel 213 and the fourth magnetic steel 214 may be sequentially rotated in a clockwise direction or in a counterclockwise direction by 90°. For example, the magnetizing direction of the first magnetic steel 211 is along the radial direction of the rotor back iron 100 toward the center of the circle, the second magnetic steel 212 rotates 90° clockwise from the magnetizing direction of the first magnetic steel 211 to the left side along the circumferential direction of the rotor back iron 100; the third magnetic steel 213 rotates 90° clockwise from the magnetizing direction of the second magnetic steel 212 to the side away from the center of the circle along the radial direction of the rotor back iron 100; the fourth magnetic steel 214 rotates 90° clockwise from the magnetizing direction of the third magnetic steel 213 to the right side along the circumferential direction of the rotor back iron 100.

[0084] Of course, the magnetization directions of the first magnetic steel 211 , the second magnetic steel 212 , the third magnetic steel 213 and the fourth magnetic steel 214 may also be spaced apart by other angles such as 80° or 100°, and there is no special limitation on this.

[0085] By setting the magnetizing directions of the first magnetic steel 211 , the second magnetic steel 212 , the third magnetic steel 213 and the fourth magnetic steel 214 to be different, the magnetic steel array of the motor is arranged more balanced.

[0086] See also Figure 1-Figure 3 In some embodiments, the first magnetic steel 211, the second magnetic steel 212, the third magnetic steel 213 and the fourth magnetic steel 214 are closely attached to each other, so that there is no gap between adjacent magnetic steels in each magnetic steel group 210, which is beneficial to the uniformity of the magnetic field.

[0087] See also Figure 1-Figure 3 In some embodiments, the magnetization directions of the first magnetic steel 211 and the third magnetic steel 213 are opposite; the magnetization directions of the second magnetic steel 212 and the fourth magnetic steel 214 are opposite.

[0088] By setting the magnetizing directions of the first magnetic steel 211 and the third magnetic steel 213 to be opposite, and the magnetizing directions of the second magnetic steel 212 and the fourth magnetic steel 214 to be opposite, the magnetic steel group 210 can form a permanent magnet synchronous motor with a Halbach magnetic steel array, thereby making the magnetic field more concentrated and uniform, and significantly improving the utilization rate of the magnetic field and the system efficiency.

[0089] See also Figure 1-Figure 3In some embodiments, the first magnetic steel 211 and the third magnetic steel 213 are radial magnetic steels; the second magnetic steel 212 and the fourth magnetic steel 214 are tangential magnetic steels.

[0090] The radial magnetic poles are magnetic poles arranged along the radial direction of the rotor back iron 100 in the magnetizing direction; the tangential magnetic poles are magnetic poles arranged along the tangent of the circumferential direction of the rotor back iron 100 in the magnetizing direction. By setting the first magnetic steel 211 and the third magnetic steel 213 as radial magnetic steels, and the second magnetic steel 212 and the fourth magnetic steel 214 as tangential magnetic steels, the magnetic steel group 210 is not skewed along the axial direction of the rotor back iron 100.

[0091] See also Figure 1-Figure 3 In some embodiments, the central angle θ1 of the first magnetic steel 211 satisfies the condition: θ1= ; Wherein, s satisfies the condition: s=6p; p is the number of magnetic steel groups 210, and p is a positive even number greater than or equal to 2.

[0092] By setting the center angle θ1 of the first magnetic steel 211 to satisfy the above formula conditions, the center angles of each first magnetic steel 211 are the same and meet the principle of motor design. In some embodiments, p is equal to 2, so s is equal to 12. In other embodiments, p is equal to 4, and s is equal to 24. Of course, in other embodiments, p can also be equal to other positive even numbers such as 6, 8 or 10, and there is no special limitation on this.

[0093] See also Figure 1-Figure 3 In some embodiments, the central angle θ2 of the third magnetic steel 213 is the same as the central angle θ1 of the first magnetic steel 211 .

[0094] By setting the center angle θ2 of the third magnetic steel 213 to be equal to the center angle θ1 of the first magnetic steel 211 , the third magnetic steel 213 and the first magnetic steel 211 are made the same in size, which not only facilitates processing but also enables a more uniform magnetic field distribution.

[0095] See also Figure 1-Figure 3 In some embodiments, the central angle θ3 of the second magnetic steel 212 satisfies the condition: θ3= ; Wherein, s satisfies the condition: s=6p; p is the number of magnetic steel groups 210, and p is a positive even number greater than or equal to 2.

[0096] By setting the center angle θ3 of the second magnetic steel 212 to satisfy the above formula, the center angles of each second magnetic steel 212 are the same and meet the principle of motor design. In some embodiments, p is equal to 2, so s is equal to 12. In other embodiments, p is equal to 4, and s is equal to 24. Of course, in other embodiments, p can also be equal to other positive even numbers such as 6, 8 or 10, and there is no special limitation on this.

[0097] See also Figure 1-Figure 3 In some embodiments, the central angle θ4 of the fourth magnetic steel 214 is the same as the central angle θ3 of the second magnetic steel 212 .

[0098] By setting the center angle θ4 of the fourth magnetic steel 214 to be equal to the center angle θ3 of the second magnetic steel 212 , the fourth magnetic steel 214 and the second magnetic steel 212 are made the same in size, which not only facilitates processing but also enables a more uniform magnetic field distribution.

[0099] In the present application, the first magnetic steel 211 and the third magnetic steel 213 are set to be of the same size, the second magnetic steel 212 and the fourth magnetic steel 214 are set to be of the same size, and the central angle of the first magnetic steel 211 and the third magnetic steel 213 is equal to twice the central angle of the second magnetic steel 212 and the fourth magnetic steel 214, so that the size of the radial magnetic steel is larger than the size of the tangential magnetic steel, thereby making the final magnetic field more balanced.

[0100] The present application sets the size of the radial magnetic steel to be equal to twice the size of the tangential magnetic steel, thereby making the distribution of the entire magnetic field more balanced, so that the magnetic force exerted on the rotor of the motor when it rotates around its own rotation axis is more balanced, and the rotation process is smoother.

[0101] See also Figure 1-Figure 3 In some embodiments, the magnetic steel group 210 is a fan-ring structure. By setting the magnetic steel group 210 as a fan-ring structure, the magnetic steel array assembly 200 assembled by multiple magnetic steel groups 210 is a fan-ring structure, which not only facilitates the installation of the entire magnetic steel array assembly 200, but also enables the first magnetic steel 211, the second magnetic steel 212, the third magnetic steel 213 and the fourth magnetic steel 214 to be processed as a fan-ring structure on the same concentric circle, which is convenient for processing and installation alignment, and the magnetic field uniformity is better.

[0102] See also Figure 1-Figure 3 In some of the embodiments, the magnetic steel array assembly 200 is a fan-ring structure.

[0103] By configuring the magnetic steel array assembly 200 as a fan-ring structure, the sizes and angles of each magnetic steel group 210 constituting the magnetic steel array assembly 200 are the same, which facilitates processing and installation alignment, and the magnetic field generated in the end is also more balanced.

[0104] See also Figure 1-Figure 3 In some embodiments, the central angle θ5 of the magnetic steel array assembly 200 satisfies the condition: θ5= ; Wherein, s satisfies the condition: s=6p; p is the number of magnetic steel groups 210, and p is a positive even number greater than or equal to 2.

[0105] By setting the center angle θ5 of the entire magnetic steel array assembly 200 to satisfy the above formula conditions, the center angle of the magnetic steel array assembly 200 meets the principles of motor design, and the circumferential portion of the entire rotor back iron 100 occupied by the magnetic steel array assembly 200 is effectively guaranteed.

[0106] See also Figure 4-Figure 5 In some embodiments, along the radial direction of the rotor back iron 100, the magnetic steel array assembly 200 is designed to have a gradually decreasing size on the side away from the inner circumference of the rotor back iron 100; specifically, the radial direction of the rotor back iron is Figure 4 and Figure 5 xx' direction in the.

[0107] By designing the magnetic steel array assembly 200 with a gradually decreasing size structure on the side of the inner circumference facing away from the rotor back iron 100, the magnetic steel array assembly 200 has an inclined side wall, which makes it convenient for the magnetic steel array assembly 200 to be clamped with the rotor housing 320 and other structures of the permanent magnet synchronous motor, and is easier to clamp and fix, thereby reducing the magnetic steel array assembly 200 from falling off along the radial direction of the rotor back iron 100.

[0108] In one specific embodiment, the side of the inner circumference of the magnetic steel array assembly 200 facing away from the rotor back iron 100 is set to a trapezoidal structure, and the length of the bottom side of the inner circumference of the side away from the rotor back iron 100 is smaller than the length of the bottom side of the inner circumference of the side close to the rotor back iron 100, so that the magnetic steel array assembly 200 is a structure with a gradually decreasing size along the radial direction of the rotor back iron 100 toward the center of the circle, which is convenient for clamping connection with other structures such as the rotor housing 320, and is easier to clamp and fix, thereby reducing the magnetic steel array assembly 200 from falling off along the radial direction of the rotor back iron 100.

[0109] See also Figure 5 and Figure 6 In some of the embodiments, the permanent magnet synchronous motor further includes a mounting assembly 300 ; the mounting assembly 300 is configured with a snap-in groove 310 ; the rotor back iron 100 and the magnetic steel array assembly 200 are snap-into the snap-in groove 310 .

[0110] The mounting assembly 300 is provided with a snap-fit ​​groove 310 , and the rotor back iron 100 and the magnetic steel array assembly 200 are snap-fitted into the snap-fit ​​groove 310 , thereby achieving assembly and fixation of the two, which is relatively simple and convenient.

[0111] See also Figure 5-Figure 6 Combined with Figure 7 In some embodiments, the mounting assembly 300 includes: a rotor housing 320, which is configured with a first accommodating cavity 321, the first accommodating cavity 321 has a first opening 3211 along the radial direction of the rotor back iron 100, and has a second opening 3212 along the axial direction of the rotor back iron 100; specifically, the axial direction of the rotor back iron is Figure 5 The direction indicated by the axis p3 in Figure 5-Figure 7 The first opening 3211 is connected to the second opening 3212. Figure 5-Figure 6 Combined with Figure 8 In some embodiments, the mounting assembly 300 further includes an end plate 330, which is mounted at the second opening 3212 of the rotor housing 320. The end plate 330 is configured with a second accommodating cavity 331. The second accommodating cavity 331 has a third opening 3311 along the axial direction of the rotor back iron 100. The third opening 3311 is arranged opposite to the second opening 3212. The second accommodating cavity 331 and the first accommodating cavity 321 are jointly arranged to form a snap-in groove 310.

[0112] By constructing a first accommodating cavity 321 with a first opening 3211 and a second opening 3212 on the rotor housing 320, and constructing a second accommodating cavity 331 with a third opening 3311 on the end plate 330, when the end plate 330 is installed on the rotor housing 320, the first accommodating cavity 321 and the second accommodating cavity 331 can jointly form a snap-in groove 310, thereby facilitating the snap-in of the rotor back iron 100 and the magnetic steel array assembly 200.

[0113] Specifically, after the magnetic steel array assembly 200 is installed on the rotor back iron 100, the following is formed: Figure 4 In the structure shown, the magnetic steel array assembly 200 and the rotor back iron 100 are first installed on the rotor housing 320 through the first opening 3211 and the second opening 3212, and then the end plate 330 is installed with the rotor housing 320 through the second opening 3212. In this way, the assembly of the magnetic steel array assembly 200 and the rotor back iron 100 with the installation assembly 300 is realized, which is relatively simple and convenient.

[0114] In one specific embodiment, the rotor back iron 100 and the magnetic steel array assembly 200 can be connected to the rotor housing 320 by shrink fitting. The end plate 330 is connected to the rotor housing 320 by threaded connectors.

[0115] See also Figure 7 In some embodiments, the first accommodating cavity 321 extends along the radial direction of the rotor back iron 100 and the cavity wall away from the end plate 330 includes a first side wall 3213 and a second side wall 3214. The first side wall 3213 is parallel to the radial direction of the rotor back iron 100; the second side wall 3214 is connected to the first side wall 3213 and is located on the side close to the first opening 3211; the second side wall 3214 extends obliquely toward the side close to the end plate 330 away from the end of the first side wall 3213; one of the side walls of the rotor back iron 100 along its axial direction is in contact with the first side wall 3213; and one of the side walls of the magnetic steel array assembly 200 along the axial direction of the rotor back iron 100 is in contact with the second side wall 3214.

[0116] The cavity wall of the first accommodating cavity 321 extending in the radial direction of the rotor back iron 100 and away from the end plate 330 is set as the first side wall 3213 and the second side wall 3214, and the second side wall 3214 is an inclined extending side wall. The first side wall 3213 is fitted with the fifth side wall 220 of the rotor back iron 100, and the second side wall 3214 is fitted with the inclined side wall of the magnetic steel array assembly 200, so that the possibility of the magnetic steel array assembly 200 falling off in the radial direction of the rotor back iron 100 can be reduced by fitting the first side wall 3213 and the second side wall 3214.

[0117] See also Figure 8 In some embodiments, the second accommodating cavity 331 extends along the radial direction of the rotor back iron 100 and includes a cavity wall on the side away from the rotor housing 320, including a third side wall 3312 and a fourth side wall 3313. The third side wall 3312 is parallel to the radial direction of the rotor back iron 100; the fourth side wall 3313 is connected to the third side wall 3312 and is located on the side close to the first opening 3211; the end of the fourth side wall 3313 away from the third side wall 3312 extends obliquely toward the side close to the rotor housing 320; another side wall of the rotor back iron 100 along its axial direction is in contact with the third side wall 3312; another side wall of the magnetic steel array assembly 200 along the axial direction of the rotor back iron 100 is in contact with the fourth side wall 3313.

[0118] The cavity wall of the second accommodating cavity 331 extending in the radial direction of the rotor back iron 100 and away from the rotor housing 320 is set as the third side wall 3312 and the fourth side wall 3313, and the fourth side wall 3313 is an inclined extending side wall. The third side wall 3312 is fitted with the sixth side wall 230 of the rotor back iron 100, and the fourth side wall 3313 is fitted with the inclined side wall of the magnetic steel array assembly 200, so that the possibility of the magnetic steel array assembly 200 falling off in the radial direction of the rotor back iron 100 can be reduced by the fitting of the third side wall 3312 and the fourth side wall 3313.

[0119] See also Figure 1 In some of the embodiments, the permanent magnet synchronous motor further includes a filling piece 400 ; the filling piece 400 is connected to the head and tail opposite ends of the magnetic steel array assembly 200 .

[0120] By arranging the filler 400 at the end-to-end opposite positions of the magnetic steel array assembly 200 that is not connected end to end, the filler 400 and the magnetic steel array assembly 200 can form a circular ring structure with a more balanced shape, structure and weight. When the rotor back iron 100 rotates with the rotor shaft, the more balanced circular ring structure formed by the magnetic steel array assembly 200 and the filler 400 installed on its inner circumference can make the rotation process of the rotor back iron 100 more stable.

[0121] In some embodiments, the filler 400 is a soft magnetic filler. By setting the filler 400 as a soft magnetic filler, the soft magnetic filler can have a higher magnetic permeability, so that when the permanent magnet synchronous motor is powered on, the entire magnetic steel array assembly 200 and the soft magnetic filler can form a more balanced magnetic structure together, thereby generating a more stable magnetic field; and when the motor is powered off, the magnetization intensity of the soft magnetic filler can be quickly reduced to near zero.

[0122] See also Figure 1 In some embodiments, the central angle θ6 of the filler 400 satisfies the condition: θ6= ; Wherein, s satisfies the condition: s=6p; p is the number of magnetic steel groups 210, and p is a positive even number greater than or equal to 2.

[0123] By setting the center angle θ6 of the filling piece 400 to satisfy the above-mentioned formula, the sum of the center angle θ6 of the filling piece 400 and the center angle θ5 of the magnetic steel array assembly 200 is 360°, that is, a complete circular ring structure, so that the circular ring structure formed by the magnetic steel array assembly 200 and the filling piece 400 has better dynamic balance when the rotor back iron 100 rotates, so that the rotation process of the rotor back iron 100 is more balanced, and the generated magnetic field is also more balanced.

[0124] In some other embodiments, p is equal to 4, and s is equal to 24. Of course, in other embodiments, p may also be equal to other positive even numbers such as 6, 8 or 10, and no special limitation is made thereto.

[0125] The permanent magnet synchronous motor provided in the embodiment of the present application does not connect the head and tail of the magnetic steel array assembly 200, and sets soft magnetic filling pieces at the positions where the head and tail of the magnetic steel array assembly 200 are opposite to each other, and at the same time limits the size of the center angle θ5 of the magnetic steel group 210 and the center angle θ6 of the soft magnetic filling piece, so that the permanent magnet synchronous motor can significantly reduce the cogging torque while maintaining the original output torque capacity. And the arrangement of the magnetic steel array assembly 200 provided in the permanent magnet synchronous motor provided in the embodiment of the present application has good repeatability and applicability, and is suitable for the manufacture of motors of different sizes and types.

[0126] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A permanent magnet synchronous motor, characterized in that: The permanent magnet synchronous motor comprises: a rotor back iron (100); and A magnetic steel array assembly (200), the magnetic steel array assembly (200) being arranged on the inner circumferential surface of the rotor back iron (100) and being constructed as a continuous structure extending in the circumferential direction of the rotor back iron (100); the magnetic steel array assembly (200) comprising a plurality of magnetic steel groups (210) connected in sequence in the circumferential direction of the rotor back iron (100); Wherein, along the circumferential direction of the rotor back iron (100), there is a gap between the head and the tail of the magnetic steel array assembly (200).

2. The permanent magnet synchronous motor according to claim 1, characterized in that: The central axes of the two groups of magnetic steel groups (210) arranged opposite to each other along the radial direction of the rotor back iron (100) are arranged at an angle.

3. The permanent magnet synchronous motor according to claim 1, characterized in that: Each of the magnetic steel groups (210) comprises a first magnetic steel (211), a second magnetic steel (212), a third magnetic steel (213), and a fourth magnetic steel (214) which are arranged in sequence; The magnetization directions of the first magnetic steel (211), the second magnetic steel (212), the third magnetic steel (213) and the fourth magnetic steel (214) are all different.

4. The permanent magnet synchronous motor according to claim 3, characterized in that: The magnetization directions of the first magnetic steel (211) and the third magnetic steel (213) are opposite; The magnetization directions of the second magnetic steel (212) and the fourth magnetic steel (214) are opposite.

5. The permanent magnet synchronous motor according to claim 3, characterized in that: The first magnetic steel (211) and the third magnetic steel (213) are radial magnetic steels; The second magnetic steel (212) and the fourth magnetic steel (214) are tangential magnetic steels.

6. The permanent magnet synchronous motor according to any one of claims 3 to 5, characterized in that: The center angle θ1 of the first magnetic steel (211) satisfies the condition: θ1= ; Among them, s satisfies the conditions: s=6p; p is the number of the magnetic steel groups (210), and p is a positive even number greater than or equal to 2.

7. The permanent magnet synchronous motor according to claim 6, characterized in that: The center angle θ2 of the third magnetic steel (213) is the same as the center angle θ1 of the first magnetic steel (211).

8. The permanent magnet synchronous motor according to any one of claims 3 to 5, characterized in that: The center angle θ3 of the second magnetic steel (212) satisfies the condition: θ3= ; Among them, s satisfies the conditions: s=6p; p is the number of the magnetic steel groups (210), and p is a positive even number greater than or equal to 2.

9. The permanent magnet synchronous motor according to claim 8, characterized in that: The center angle θ4 of the fourth magnetic steel (214) is the same as the center angle θ3 of the second magnetic steel (212).

10. The permanent magnet synchronous motor according to any one of claims 1 to 5, characterized in that: The magnetic steel group (210) is a fan-ring structure.

11. The permanent magnet synchronous motor according to any one of claims 1 to 5, characterized in that: The magnetic steel array component (200) is a fan-ring structure.

12. The permanent magnet synchronous motor according to claim 11, characterized in that: The center angle θ5 of the magnetic steel array assembly (200) satisfies the condition: θ5= ; Among them, s satisfies the conditions: s=6p; p is the number of the magnetic steel groups (210), and p is a positive even number greater than or equal to 2.

13. The permanent magnet synchronous motor according to any one of claims 1 to 5, characterized in that: Along the radial direction of the rotor back iron (100), the side of the inner circumferential surface of the magnetic steel array assembly (200) facing away from the rotor back iron (100) is designed as a structure with gradually decreasing size.

14. The permanent magnet synchronous motor according to claim 13, characterized in that: The permanent magnet synchronous motor also includes a mounting assembly (300); The installation assembly (300) is configured with a snap-in groove (310); The rotor back iron (100) and the magnetic steel array assembly (200) are clamped in the clamping groove (310).

15. The permanent magnet synchronous motor according to claim 14, characterized in that: The installation assembly (300) comprises: The rotor housing (320) is configured with a first accommodating cavity (321), the first accommodating cavity (321) having a first opening (3211) along the radial direction of the rotor back iron (100), and a second opening (3212) along the axial direction of the rotor back iron (100); the first opening (3211) and the second opening (3212) are in communication; an end plate (330) mounted at the second opening (3212) of the rotor housing (320), the end plate (330) being configured with a second accommodating cavity (331), the second accommodating cavity (331) having a third opening (3311) along the axial direction of the rotor back iron (100); the third opening (3311) being arranged opposite to the second opening (3212); The second accommodating cavity (331) and the first accommodating cavity (321) are jointly arranged to form the clamping groove (310).

16. The permanent magnet synchronous motor according to claim 15, characterized in that: The cavity wall of the first accommodating cavity (321) extending in the radial direction of the rotor back iron (100) and away from the end plate (330) comprises: A first side wall (3213) is parallel to the radial direction of the rotor back iron (100); a second side wall (3214), connected to the first side wall (3213) and located on a side close to the first opening (3211); an end of the second side wall (3214) away from the first side wall (3213) extends obliquely toward a side close to the end plate (330); One of the side walls of the rotor back iron (100) along its axial direction is in contact with the first side wall (3213); One of the side walls of the magnetic steel array assembly (200) along the axial direction of the rotor back iron (100) is fitted to the second side wall (3214).

17. The permanent magnet synchronous motor according to claim 15, characterized in that: The second accommodating cavity (331) extends in the radial direction of the rotor back iron (100) and has a cavity wall away from the rotor housing (320) and comprises: A third side wall (3312) is parallel to the radial direction of the rotor back iron (100); a fourth side wall (3313) connected to the third side wall (3312) and located on a side close to the first opening (3211); an end of the fourth side wall (3313) away from the third side wall (3312) extends obliquely toward a side close to the rotor housing (320); Another side wall of the rotor back iron (100) along its axial direction is in contact with the third side wall (3312); Another side wall of the magnetic steel array assembly (200) along the axial direction of the rotor back iron (100) is fitted to the fourth side wall (3313).

18. The permanent magnet synchronous motor according to any one of claims 1 to 5, characterized in that: The permanent magnet synchronous motor also includes a filling piece (400); The filling piece (400) is connected to the magnetic steel array assembly (200) at the ends thereof.

19. The permanent magnet synchronous motor according to claim 18, characterized in that: The filling piece (400) is a soft magnetic filling piece.

20. The permanent magnet synchronous motor according to claim 18, characterized in that: The center angle θ6 of the filling piece (400) satisfies the condition: θ6= ; Among them, s satisfies the conditions: s=6p; p is the number of the magnetic steel groups (210), and p is a positive even number greater than or equal to 2.

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