CN107017750B - Motor - Google Patents

Abstract

The present invention provides a motor, which includes: a stator structure, including a stator core and a stator cavity, the stator core is provided with stator slots, the stator slots are arranged obliquely along the axial direction of the stator core, and the windings of the stator structure are arranged on the stator core in a star connection method; a rotor structure is arranged in the stator cavity, and three magnetic steels are arranged on each magnetic pole of the rotor structure. The technical solution of the present invention is applied to solve the problem of complex production and assembly of motors in the prior art.

Description

Motor

Technical Field

The present invention relates to the technical field of motors, and in particular to a motor.

Background technique

In a built-in permanent magnet motor, the motor air gap magnetic flux waveform close to the sinusoidal distribution can reduce the harmonic components while reducing the eddy current loss and torque pulsation of the magnetic steel. In the prior art, in order to make the motor air gap magnetic flux waveform close to the sinusoidal distribution, the entire magnetic steel of each pole of the rotor can be divided into as many magnetic steels of the same polarity as possible with different widths, and magnetic insulation reinforcement ribs are provided between each magnetic steel segment. From the electromagnetic performance analysis, an odd number of step waves are used to approximate the sinusoidal magnetic flux density, and the width of each magnetic steel segment is modulated by using the method of equal area of each step wave segment to achieve the purpose of the motor air gap magnetic flux waveform close to the sinusoidal distribution. In this way, when the number of segments of the magnetic steel is too large, it is easy to cause the rotor structure to be complicated, which brings great difficulty to the production and assembly of the motor.

Summary of the invention

The present invention provides a motor to solve the problem of complex production and assembly of motors in the prior art.

The present invention provides a motor, which comprises: a stator structure, comprising a stator core and a stator cavity, wherein the stator core is provided with stator slots, the stator slots are arranged obliquely along the axial direction of the stator core, and the windings of the stator structure are arranged on the stator core in a star connection; a rotor structure, which is arranged in the stator cavity, and each magnetic pole of the rotor structure is provided with three magnets.

Furthermore, the rotor structure includes a rotor core, and three magnets are arranged in an arc shape on the rotor core, and the arc opening faces the center of the rotor core.

Furthermore, the rotor core has a plurality of sector-shaped areas in a radial cross section, and the plurality of sector-shaped areas are arranged in one-to-one correspondence with the plurality of magnetic poles. The three magnetic steels are respectively a first magnetic steel, a second magnetic steel and a third magnetic steel, wherein the center of the first magnetic steel in the radial cross section of the rotor core is located on the center line of the sector-shaped area corresponding to each pole, and the second magnetic steel and the third magnetic steel are symmetrically arranged along the center line.

Furthermore, in the radial cross section of the rotor core, the center of the rotor core is not located on the center line of the second magnetic steel along the length direction and the center line of the third magnetic steel along the length direction.

Furthermore, the lengths of the second magnetic steel and the third magnetic steel in the radial cross section are the same, and are both smaller than the length of the first magnetic steel in the radial cross section.

Furthermore, a plurality of magnetic steel mounting holes for mounting magnetic steel are provided on the rotor core, and the magnetic steel mounting holes are arranged in a one-to-one correspondence with the magnetic steels.

Furthermore, the rotor core also includes slot wedges, which are arranged in the magnetic steel mounting holes to fix the magnetic steel.

Furthermore, the side edges of the second magnetic steel and/or the third magnetic steel close to the first magnetic steel and/or the side edges of the first magnetic steel are arc structures.

Furthermore, the second magnetic steel and the third magnetic steel are both arranged at an angle with the first magnetic steel.

Furthermore, the rotor core also includes: a magnetic isolation bridge, which is arranged on the periphery of the rotor core; and a reinforcing rib, which is arranged between two adjacent magnetic steel mounting holes.

Furthermore, the rotor structure includes a plurality of rotor punchings, and positioning holes are provided on the plurality of rotor punchings.

By applying the technical solution of the present invention, when the air gap magnetic flux waveform of the motor is a sawtooth flat-top wave and the reverse electromotive force waveform of the motor is a flat-top wave, the stator slots are tilted along the axial direction of the stator core, the winding of the stator structure is arranged on the stator core in a star connection, and three magnetic steels are arranged on each magnetic pole of the rotor structure, so that the reverse electromotive force of the motor line can be modulated into a sine wave. This method of the present invention can reduce the number of magnetic steels on each magnetic pole of the rotor structure, thereby reducing magnetic leakage, which is beneficial to the assembly and production of the motor and improving the production efficiency of the motor. On this basis, by modulating the reverse electromotive force of the motor line into a sine wave, it is beneficial to reduce the harmonic component and reduce the eddy current loss and torque pulsation of the magnetic steel.

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG1 is a schematic structural diagram of a rotor structure provided by an embodiment of the present invention when magnetic steel is not installed;

FIG2 is a schematic diagram showing a structure of a rotor structure provided by an embodiment of the present invention when magnetic steel is installed;

FIG3 shows a schematic structural diagram of an air gap magnetic flux waveform provided according to an embodiment of the present invention;

FIG4 shows a schematic structural diagram of the reverse potential of a motor provided according to an embodiment of the present invention;

FIG5 shows a schematic structural diagram of the motor line back electromotive force provided according to an embodiment of the present invention.

The above drawings include the following reference numerals:

10. Rotor core; 11. Magnet; 111. First magnet; 112. Second magnet; 113. Third magnet; 12. Magnet mounting hole; 121. First magnet mounting hole; 122. Second magnet mounting hole; 123. Third magnet mounting hole; 13. Slot wedge; 14. Magnetic isolation bridge; 15. Reinforcing rib; 16. Positioning hole.

Detailed ways

It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

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

Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

In the description of the present invention, it is necessary to understand 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. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

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.

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. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

According to a specific embodiment of the present invention, a motor is provided, which includes a stator structure and a rotor structure. The stator structure includes a stator core and a stator cavity. The stator core is provided with stator slots, and the stator slots are inclined along the axial direction of the stator core. The winding of the stator structure is arranged on the stator core in a star connection method. The rotor structure is arranged in the stator cavity, and three magnets are arranged on each magnetic pole of the rotor structure.

By applying this configuration, when the air gap flux density waveform of the motor is a sawtooth flat-top wave A as shown in FIG3 and the reverse electromotive force waveform of the motor is a flat-top wave B as shown in FIG4, by tilting the stator slots along the axial direction of the stator core, the winding of the stator structure is arranged on the stator core in a star connection, and three magnets are arranged on each magnetic pole of the rotor structure, the reverse electromotive force of the motor line can be modulated into a sine wave as shown in FIG5. This method of the present invention can reduce the number of magnets on each magnetic pole of the rotor structure, thereby reducing magnetic leakage, which is beneficial to the assembly and production of the motor and improving the production efficiency of the motor. On this basis, by modulating the reverse electromotive force of the motor line into a sine wave, it is beneficial to reduce the harmonic component and reduce the eddy current loss and torque pulsation of the magnet.

Further, in the present invention, the rotor structure includes a rotor core 10, and three magnets 11 are arranged in an arc shape on the rotor core 10, and the arc opening faces the center of the rotor core 10. Specifically, as a specific embodiment of the present invention, the structure of the magnet 11 is a rectangular parallelepiped structure, and the magnetization direction of the magnet 11 is perpendicular to the surface of the magnet 11. Figures 1 and 2 show schematic diagrams of a rotor structure with four poles. As other embodiments of the present invention, the rotor structure of the present invention is also applicable to six-pole or eight-pole motors.

In the present invention, in order to make the distribution of the magnetic field in the rotor structure more uniform, the rotor core 10 can be configured to have multiple sector-shaped areas in the radial section, and the multiple sector-shaped areas are arranged in one-to-one correspondence with the multiple magnetic poles. The three magnetic steels are the first magnetic steel 111, the second magnetic steel 112 and the third magnetic steel 113, wherein the center of the first magnetic steel 111 in the radial section of the rotor core 10 is located on the center line of the sector-shaped area corresponding to each pole, and the second magnetic steel 112 and the third magnetic steel 113 are symmetrically arranged along the center line.

With this configuration, the second magnetic steel 112 and the third magnetic steel 113 are symmetrically arranged along the center line. This structure is beneficial for the magnets of each pair of poles of the rotor structure to correspond, thereby making the magnetic field distribution in the entire rotor structure more uniform.

Furthermore, in the present invention, in order to improve the mechanical strength of the rotor structure, in the radial section of the rotor core 10, the center of the rotor core 10 is not located on the center line of the second magnetic steel 112 along the length direction and the center line of the third magnetic steel 113 along the length direction.

In the present invention, in order to further ensure the structural strength of the rotor structure, the lengths of the second magnetic steel 112 and the third magnetic steel 113 on the radial cross section can be set to be the same, and both are smaller than the length of the first magnetic steel 111 on the radial cross section. In the present invention, when the length ratio of the second magnetic steel 112 or the third magnetic steel 113 to the first magnetic steel 111 is 2:3, the rotor structural strength under this setting is maximum. Further, in the present invention, the thicknesses of the first magnetic steel 111, the second magnetic steel 112 and the third magnetic steel 113 along the axial direction of the rotor core 10 are all equal.

Further, in the present invention, in order to realize the installation of multiple magnetic steels 11 on the rotor structure, the rotor core 10 can be provided with multiple magnetic steel installation holes 12 for installing the magnetic steels 11, and the magnetic steel installation holes 12 are arranged in a one-to-one correspondence with the magnetic steels 11. Specifically, as shown in Figures 1 and 2, the multiple magnetic steel installation holes 12 are respectively a first magnetic steel installation hole 121, a second magnetic steel installation hole 122, and a third magnetic steel installation hole 123. When performing the installation operation of the multiple magnetic steels 11, the first magnetic steel 111 is arranged and installed in the first magnetic steel installation hole 121, the second magnetic steel 112 is arranged and installed in the second magnetic steel installation hole 122, and the third magnetic steel 113 is arranged and installed in the third magnetic steel installation hole 123.

In the present invention, in order to facilitate the fixation of the magnetic steel 11, the rotor core 10 can be configured to further include a slot wedge 13, and the slot wedge 13 is arranged in the magnetic steel mounting hole 12 to fix the magnetic steel 11. Specifically, as a specific embodiment of the present invention, the number of slot wedges 13 for each pole of the rotor structure is two. After the second magnetic steel 112 is installed in the second magnetic steel mounting hole 122, one of the slot wedges 13 is driven into the remaining space of the second magnetic steel mounting hole 122 to fix the second magnetic steel 112. After the third magnetic steel 113 is installed in the third magnetic steel mounting hole 123, another slot wedge 13 is driven into the remaining space of the third magnetic steel mounting hole 123 to fix the third magnetic steel 113. Further, in the present invention, after the magnetic steel 11 and the magnetic steel mounting hole 12 are assembled, the gap of the magnetic steel mounting slot can be filled with magnetic steel glue to firmly fix the magnetic steel 11 in the magnetic steel mounting hole 12.

Specifically, as a specific embodiment of the present invention, when performing the installation operation of the magnetic steel 11, since the size of each magnetic steel 11 is relatively small, when installing the magnetic steel 11 into the magnetic steel installation hole 12, according to the specified direction of the magnetic steel 11 under each N and S poles of the motor, a guide fixture made of non-magnetic conductive material can be used to push the magnetic steel 11 into the magnetic steel installation hole 12. The installation process of the magnetic steel 11 using this method has good processability and high production efficiency.

Furthermore, in order to improve the structural strength of the rotor structure, as shown in FIG. 2 , the sides of the second magnetic steel 112 and/or the third magnetic steel 113 close to the first magnetic steel 111 and/or the sides of the first magnetic steel 111 may be set to an arc structure.

In the present invention, as shown in FIG. 1 and FIG. 2 , the second magnetic steel 112 and the third magnetic steel 113 are both arranged at an angle with the first magnetic steel 111. In the present invention, the angle between the second magnetic steel 112 or the third magnetic steel 113 and the first magnetic steel 111 can be set to 150° to 165°, wherein the size of the angle can be determined by comprehensively determining the motor line back electromotive force and the structural strength of the rotor structure. Specifically, when the size of the angle between the second magnetic steel 112 or the third magnetic steel 113 and the first magnetic steel 111 increases, the peak value of the motor line back electromotive force will increase, and the structural strength of the rotor structure will decrease. Conversely, when the size of the angle between the second magnetic steel 112 or the third magnetic steel 113 and the first magnetic steel 111 decreases, the peak value of the motor line back electromotive force will decrease, and the structural strength of the rotor structure will increase.

Furthermore, in the present invention, in order to further improve the structural strength of the rotor structure and improve the magnetic isolation effect of the rotor structure, the rotor core 10 can be configured to also include a magnetic isolation bridge 14 and a reinforcing rib 15, wherein the magnetic isolation bridge 14 is arranged at the periphery of the rotor core 10, and the reinforcing rib 15 is arranged between two adjacent magnetic steel mounting holes 12. Through the action of the magnetic isolation bridge 14 and the reinforcing rib 15, the centrifugal force of the rotor core 10 and the magnetic steel 11 during high-speed movement can be withstood and a magnetic isolation effect can be achieved.

In the present invention, in order to ensure the accuracy of the position of the rotor structure during the lamination process, the rotor structure can be configured to include a plurality of rotor punchings, and the plurality of rotor punchings are provided with positioning holes 16. Through the role of the positioning holes 16, the lamination positions of the plurality of rotor punchings can be ensured to be uniform, thereby improving the accuracy of the rotor structure and facilitating the subsequent assembly between the magnetic steel 11 and the magnetic steel mounting hole 12.

In summary, the motor of the present invention has the following advantages over the prior art.

First, when the air gap magnetic flux waveform of the motor is a sawtooth flat-top wave A and the reverse electromotive force waveform of the motor is a flat-top wave B, by tilting the stator slots along the axial direction of the stator core, the winding of the stator structure is arranged on the stator core in a star connection, and three magnetic steels are arranged on each magnetic pole of the rotor structure, the reverse electromotive force of the motor line can be modulated into a sine wave. This method of the present invention can reduce the number of magnetic steels on each magnetic pole of the rotor structure, thereby reducing magnetic leakage, which is beneficial to the assembly and production of the motor and improving the production efficiency of the motor. On this basis, by modulating the reverse electromotive force of the motor line into a sine wave, it is beneficial to reduce the harmonic component and reduce the eddy current loss and torque pulsation of the magnetic steel.

Second, by setting the side of the second magnetic steel and/or the third magnetic steel close to the first magnetic steel and/or the side of the first magnetic steel to be an arc structure, the structural strength of the rotor structure can be improved.

Third, in the radial cross section of the rotor core, by locating the center of the first magnetic steel in the radial cross section of the rotor core on the center line of the sector area corresponding to each pole, in the radial cross section of the rotor core 10, the center of the rotor core 10 is not located on the center line of the second magnetic steel 112 along the length direction and the center line of the third magnetic steel 113 along the length direction, thereby improving the structural strength of the rotor structure.

Fourth, by arranging the magnetic steel in sections, the stress at the magnetic isolation bridge of the rotor structure and the deformation at the middle position of the adjacent magnetic isolation bridges can be reduced, and the maximum stress point is dispersed from the magnetic isolation bridge to multiple reinforcing ribs with strong bearing capacity, thereby improving the mechanical strength of the rotor structure. Furthermore, the width of each reinforcing rib is determined by the maximum speed of the motor, which can greatly increase the maximum speed of the rotor's safe operation.

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

Claims (9)

1. A motor, characterized in that the motor comprises: The stator structure comprises a stator core and a stator cavity, wherein the stator core is provided with stator slots, the stator slots are arranged obliquely along the axis direction of the stator core, and the winding of the stator structure is arranged on the stator core in a star connection; A rotor structure is arranged in the stator cavity, and three magnetic steels are arranged on each magnetic pole of the rotor structure; The rotor structure comprises a rotor core (10), and the three magnetic steels (11) are arranged in an arc shape on the rotor core (10), with the arc opening facing the center of the rotor core (10); The rotor core (10) has a plurality of sector-shaped regions in a radial cross section, the plurality of sector-shaped regions are arranged in one-to-one correspondence with the plurality of magnetic poles, the three magnetic steels are respectively a first magnetic steel (111), a second magnetic steel (112) and a third magnetic steel (113), wherein the center of the first magnetic steel (111) in a radial cross section of the rotor core (10) is located on a center line of the sector-shaped regions corresponding to each pole, and the second magnetic steel (112) and the third magnetic steel (113) are symmetrically arranged along the center line; The second magnetic steel (112) and the third magnetic steel (113) are both arranged at an angle with the first magnetic steel (111), and the angle is in the range of 150° to 165°. 2. The motor according to claim 1 is characterized in that, in a radial cross section of the rotor core (10), the center of the rotor core (10) is not located on a center line of the second magnetic steel (112) along the length direction and a center line of the third magnetic steel (113) along the length direction. 3. The motor according to claim 1 is characterized in that the lengths of the second magnetic steel (112) and the third magnetic steel (113) in the radial cross section are the same, and both are smaller than the length of the first magnetic steel (111) in the radial cross section. 4. The motor according to claim 2 is characterized in that a plurality of magnetic steel mounting holes (12) for mounting the magnetic steel (11) are provided on the rotor core (10), and the magnetic steel mounting holes (12) are arranged in a one-to-one correspondence with the magnetic steel (11). 5. The motor according to claim 4 is characterized in that the rotor core (10) further comprises a slot wedge (13), and the slot wedge (13) is arranged in the magnetic steel mounting hole (12) to fix the magnetic steel (11). 6. The motor according to claim 1, characterized in that the side of the second magnetic steel (112) and/or the third magnetic steel (113) close to the first magnetic steel (111) and/or the side of the first magnetic steel (111) is an arc structure. 7. The motor according to claim 1, characterized in that the second magnetic steel (112) and the third magnetic steel (113) are both arranged at an angle with the first magnetic steel (111). 8. The motor according to claim 4, characterized in that the rotor core (10) further comprises: A magnetic isolation bridge (14) is arranged on the periphery of the rotor core (10); A reinforcing rib (15) is arranged between two adjacent magnetic steel mounting holes (12). 9. The motor according to claim 1, characterized in that the rotor structure comprises a plurality of rotor punchings, and the plurality of rotor punchings are provided with positioning holes (16).