CN113078791A

CN113078791A - Synchronous machine

Info

Publication number: CN113078791A
Application number: CN202110418923.9A
Authority: CN
Inventors: 孙天夫; 龙凌辉; 冯伟; 梁嘉宁; 李慧云; 石印洲
Original assignee: Shenzhen Institute of Advanced Technology of CAS
Current assignee: Shenzhen Institute of Advanced Technology of CAS
Priority date: 2021-04-19
Filing date: 2021-04-19
Publication date: 2021-07-06

Abstract

The invention relates to the technical field of motors, and provides a synchronous motor which comprises a stator part and a rotor part matched with the stator part, wherein an air gap space is formed between the stator part and the rotor part, and a fluid magnetizer is filled in the air gap space. An air gap space is formed between the stator part and the rotor part, and the air gap space is filled with a fluid magnetizer. Namely, the air gap space is filled by the fluid magnetizer, thereby reducing the magnetic leakage problem of the stator part and the rotor part and increasing the torque density. Therefore, under the condition of a certain working current, the torque output of the synchronous motor is obviously improved.

Description

Synchronous machine

Technical Field

The invention relates to the technical field of motors, and particularly provides a synchronous motor.

Background

Synchronous motors are classified into permanent magnet synchronous motors, reluctance synchronous motors and hysteresis synchronous motors, and synchronous motors have been widely used in the fields of aerospace, industrial automation, electric vehicles and the like because of their advantages of high power, high efficiency, high torque density and the like.

Then, when the working current of the synchronous motor is limited, the magnetic strength of the motor and the torque of the motor cannot be further improved.

Disclosure of Invention

The invention aims to provide a synchronous motor, and aims to solve the problem that the performance of the conventional synchronous motor cannot be improved under the condition that the working current is limited.

In order to achieve the purpose, the invention adopts the technical scheme that: a synchronous motor comprises a stator part and a rotor part matched with the stator part, wherein an air gap space is formed between the stator part and the rotor part, and a fluid magnetizer is filled in the air gap space.

In one embodiment, the stator part includes a stator main body, the rotor part includes a rotor main body and a plurality of permanent magnet structural members, a plurality of mounting grooves adapted to the contour of the permanent magnet structural members are formed on the outer side wall of the rotor main body, each permanent magnet structural member is mounted in the corresponding mounting groove, and the air gap space is formed between the stator main body and the rotor main body as well as between the stator main body and the permanent magnet structural members.

In one embodiment, the permanent magnet structural member comprises two magnetic arms with one ends arranged oppositely, and an included angle between the magnetic arms is gradually reduced along the direction of the notch of the mounting groove.

In one embodiment, the permanent magnet structure further comprises a magnet holder for connecting the two magnet arms.

In one embodiment, the permanent magnet structural member comprises two magnetic arms, one end of each magnetic arm is arranged to be away from the other end of each magnetic arm, and an included angle between the magnetic arms is gradually increased along the direction of the groove opening of the mounting groove.

In one embodiment, a plurality of magnetic resistance members are arranged in the air gap space at intervals, each magnetic resistance member separates the air gap space to form a plurality of independent air gap subspaces, and the fluid magnetizer is filled in the air gap subspaces.

In one embodiment, a plurality of magnetic resistance pieces are arranged in the air gap space at intervals, and each magnetic resistance piece is arranged at the end part of the magnetic arm; at the end parts of the two magnetic arms of the same permanent magnetic structural member, the two magnetism resisting parts, the stator main body and the rotor main body are enclosed to form a first air gap subspace; at the end parts of two adjacent magnetic arms of two adjacent permanent magnetic structural members, the two magnetic resistance members, the stator main body and the rotor main body are enclosed to form a second air gap subspace, and the fluid magnetizer is filled in the second air gap subspace.

In one embodiment, the stator part comprises a stator body, the rotor part comprises a rotor body, the outer side of the rotor body is provided with a plurality of protruding structures, and the air gap space is formed between the stator body and the rotor body and between the stator body and each protruding structure.

In one embodiment, the rotor body is a non-magnetic conductive rotor body.

In one embodiment, the air gap space is a cavity formed between two adjacent protruding structures, and the fluid magnetizer is filled in the cavity.

In one embodiment, the stator portion further comprises a plurality of windings wound on the stator body.

The invention has the beneficial effects that: according to the synchronous motor provided by the invention, an air gap space is formed between the stator part and the rotor part, and the air gap space is filled with the fluid magnetizer. Namely, the air gap space is filled by the fluid magnetizer, thereby reducing the magnetic leakage problem of the stator part and the rotor part and increasing the torque density. Therefore, under the condition of a certain working current, the torque output of the synchronous motor is obviously improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a cross-sectional view of a synchronous machine according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of a synchronous machine according to an embodiment of the present invention;

fig. 3 is a cross-sectional view of a synchronous machine according to an embodiment of the present invention;

fig. 4 is a cross-sectional view of a synchronous motor according to an embodiment of the present invention.

Wherein, in the figures, the respective reference numerals:

the permanent magnet motor comprises a stator part 10, a rotor part 20, an air gap space 30, a fluid magnetizer 40, a stator main body 11, a rotor main body 21, a permanent magnet structural part 22, a mounting groove 21a, a first permanent magnet 221, a second permanent magnet 222, a magnetism blocking part 50, an air gap subspace 31, a protruding structure 23 and a winding 12.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In general, in a synchronous machine, there is a reluctance, which is a parameter in a magnetic circuit containing permanent magnets, resulting from the presence of leakage flux in the magnetic circuit. When the permanent magnet generates a working magnetic field, three parts, namely the permanent magnet, the high-permeability soft magnet and an air gap with proper size, are required to be arranged, and the three parts are collectively called a magnetic circuit. The permanent magnets provide magnetic flux and generate a magnetic field at the air gap after passing through the soft magnet connection. The total magnetic flux in the magnetic circuit is conserved but the flux density at the air gap is relatively reduced because part of the flux is lost at the non-air gap, known as leakage flux, resulting in reluctance in the magnetic circuit. Meanwhile, the torque density of the synchronous motor is limited by an air gap between the stator and the rotor, so that the magnetic field intensity and the torque density of the synchronous motor cannot be further improved under the condition of certain working current of the synchronous motor. Moreover, due to the influence of the processing technology, the air gap between the stator and the rotor cannot be infinitely reduced. In summary, in order to solve the problem that the magnetic field strength and the torque density of the synchronous motor cannot be further improved under a certain input current, the present application provides the following technical solutions, specifically please refer to the following embodiments:

referring to fig. 1, the synchronous machine of the present application includes a stator portion 10 and a rotor portion 20 fitted to the stator portion 10. The rotor portion 20 is capable of rotating about its axis relative to the stator portion 10 under the influence of a magnetic field. An air gap space 30 is formed between the stator portion 10 and the rotor portion 20, the air gap space 30 is used for realizing the rotation of the rotor portion 20 around the axis relative to the stator portion 10, and the air gap space 30 is filled with a fluid magnetizer 40. Here, the fluid magnetizer 40 is a magnetic conductive substance in a fluid state, and can flow in the air gap space 30. For example, the fluid magnetizer 40 is a liquid magnetorheological fluid, which fills the air gap space 30 and fills the air gap space 30, thereby improving the magnetic flux communication between the rotor portion 20 and the stator portion 10. Alternatively, fluid magnetizer 40 is a plurality of spherical magnetizer beads having a diameter small enough to flow in air gap space 30 and fill air gap space 30. Similarly, the magnetic conductor beads filled in the air gap space 30 can also satisfy the requirement that the rotor portion 20 rotates around the shaft relative to the stator portion 10, and simultaneously, the magnetic flux circulation between the rotor portion and the stator portion is improved, and the magnetic field intensity is prevented from being attenuated at the air gap space 30.

In the synchronous motor of the present application, a fluid magnetizer 40 is filled in an air gap space 30 between a stator portion 10 and a rotor portion 20. The fluid magnetizer 40 is used for filling the air gap space 30, so that the flux circulation at the air gap space 30 is improved, and thus, under the condition that a certain working current is applied to the synchronous motor or the working current is limited, the influence of the air gap space 30 on the magnetic field intensity can be reduced, and the torque density of the synchronous motor is further improved.

Referring to fig. 1 and 2, in one embodiment, the stator portion 10 includes a stator body 11, and the stator body 11 forms a magnetic field in an energized state, for example, the stator body 11 is energized with three-phase alternating current. The rotor portion 20 includes a rotor main body 21 and a plurality of permanent magnet structural members 22, the rotor main body 21 is a carrier, and each permanent magnet structural member 22 forms a magnetic field to interact with a magnetic field formed by the energized stator main body 11, so that the rotor main body 21 rotates around an axis relative to the stator main body 11. The rotor body 21 is provided with a plurality of mounting grooves adapted to the contour of the permanent magnet structural member 22, and here, the mounting positions of the mounting grooves are described, for example, the side wall of the rotor body 21 is provided with a plurality of mounting grooves 21a, each mounting groove 21a is arranged at intervals with the central axis of the rotor body 21 as the rotation center, specifically, ten mounting grooves 21a are provided on the rotor body 21, and correspondingly, a permanent magnet structural member 22 is arranged at each of the ten mounting grooves 21a, and of course, the number of the permanent magnet structural members 22 and the number of the mounting grooves 21a can be adjusted according to actual requirements. Alternatively, if a plurality of mounting grooves 21a are formed in the rotor body 21, the permanent magnet structural members 22 are inserted into the corresponding mounting grooves 21a from the end of the rotor body 21 when they are mounted. Each permanent magnet structural member 22 is installed in the corresponding installation groove 21a, and the groove structure of the installation groove 21a is matched with the outline of the permanent magnet structural member 22, so as to ensure the installation mechanical strength of each permanent magnet structural member 22, and the magnetic poles of two adjacent permanent magnet structural members 22 are opposite. It will be appreciated that, for example, the N pole of the first permanent magnet structure 22 faces outwardly and the S pole of the adjacent permanent magnet structure 22 faces outwardly, so that the overall magnetic circuit is the N pole of one permanent magnet structure 22, the air gap space 30, the stator body 11, the air gap space 30 and the S pole of the other permanent magnet structure 22.

Specifically, referring to the figures, the shape of the permanent magnet structure 22 can be adjusted according to actual needs. For example, the permanent magnet structure 22 includes two first permanent magnets 221 with one end facing each other, and similarly, when the permanent magnets are placed, the S pole or the N pole of each first permanent magnet 221 is also directed outward. In one case, the included angle between the two first permanent magnets 221 is gradually reduced along the direction of the notch of the mounting groove 21a, that is, the opening of the permanent magnet structural member 22 is in a necking state, so that the magnetic concentration effect is better, and the magnetic strength of the synchronous motor can be increased; in another case, the included angle between the two first permanent magnets 221 gradually increases along the direction of the notch of the mounting groove 21a, that is, the opening of the permanent magnet structural member 22 is in a flaring state, the magnetic gathering effect of the flaring permanent magnet structural member 22 is relatively reduced, and the permanent magnet structural member is suitable for synchronous motors under the requirements of other pole slot matching and torque density.

Optionally, referring to fig. 2 and fig. 3, the permanent magnet structure 22 further includes a first permanent magnet 222 for connecting the other ends of the two first permanent magnets 221, and the first permanent magnet 222 and the two first permanent magnets 221 enclose the cross section of the rotor main body 21 to form the U-shaped permanent magnet structure 22. It is understood that each first permanent magnet 221 and the plurality of first permanent magnets 222 form the U-shaped permanent magnet structural member 22, which also follows the same outward polarity, i.e., S-pole or N-pole. Meanwhile, the opening of the U-shaped permanent magnet structural member 22 faces the stator body 11, i.e., the magnetic path direction is ensured to face the stator body 11.

In one embodiment, the permanent magnet structure 22 is also U-shaped, and the difference from the above embodiments is that the number of the first permanent magnets 221 and the number of the first permanent magnets 222 of the permanent magnet structure 22 are different, that is, at least two or more first permanent magnets 221 are sequentially connected to form a vertical portion of the U-shaped structure, and at least two or more first permanent magnets 222 are sequentially connected to form a horizontal portion of the U-shaped structure.

In another embodiment, the permanent magnet structure 22 includes two first permanent magnets 221 with one end abutting and the other end facing away from each other, and an included angle between the two first permanent magnets 221 gradually increases along the direction of the slot opening of the mounting slot 21 a. Likewise, the permanent magnet structure 22 in this case also follows the principle of uniform polarity. It can be understood that the permanent magnet structure 22 in this embodiment is V-shaped, and the opening direction thereof is toward the stator body 11, i.e. the magnetic path direction is ensured toward the stator body 11.

Referring to fig. 2 and fig. 3, in an embodiment, a plurality of magnetic blocking members 50 are disposed at intervals in the air gap space 30, where the magnetic blocking members 50 are non-magnetic conductive metal structural members or structural members made of other materials, and function to prevent the magnetic paths between two adjacent permanent magnetic structural members 22 from being communicated, that is, to prevent a path from being formed between an N pole of one adjacent permanent magnetic structural member 22 and an S pole of another permanent magnetic structural member 22, which does not pass through the stator, thereby reducing unnecessary magnetic flux leakage. Meanwhile, the arrangement position of each magnetic resistance piece 50 can also be selected, that is, each magnetic resistance piece 50 is arranged on one side of the stator main body 11 facing the rotor main body 21, that is, each magnetic resistance piece 50 is static relative to the rotor main body 21; alternatively, each magnetic resistance member 50 is provided on the side of the rotor body 21 facing the stator body 11, that is, each magnetic resistance member 50 rotates around the shaft together with the rotor body 21. Meanwhile, due to the addition of the magnetic resistance pieces 50, the air gap space 30 is separated to form a plurality of independent air gap subspaces 31, and it can be understood that each air gap subspace 31 is also separated and independently arranged by each magnetic resistance piece 50, and the fluid magnetizer 40 is filled in the corresponding air gap subspaces 31. Here, the air gap subspace 31 and the opening of the permanent magnet structure 22 may correspond completely or partially, i.e. the fluid magnetizer 40 of the air gap subspace 31 may have the following conditions: firstly, the fluid magnetizer 40 of the air gap subspace 31 completely corresponds to the opening of the permanent magnet structural member 22, at this time, the magnetic resistance effect of the magnetic resistance member 50 is the best, and the magnetic conduction effect of the fluid magnetizer 40 is also the best, and the magnetic circuit of two adjacent permanent magnet structural members 22 has no magnetic leakage problem. Secondly, the fluid magnetizer 40 of the air gap subspace 31 corresponds to the opening part of the permanent magnet structural member 22, and at this time, the air gap subspace 31 is staggered with the opening of the permanent magnet structural member 22, so that the fluid magnetizer 40 is partially outside the opening of the permanent magnet structural member 22, which can satisfy the flux circulation, but the effect is relatively poor. Thirdly, the air gap subspace 31 is larger than the opening of the permanent magnet structure 22 and also completely corresponds to it. At this time, the magnetic blocking effect of the magnetic blocking member 50 and the magnetic conduction effect of the fluid magnetizer 40 are both preferable.

Specifically, referring to fig. 2, in one embodiment, each magnetic blocking member 50 is located between the first permanent magnets 221 of two adjacent permanent magnet structural members 22. It is understood that, in this case, the air gap sub-space 31 formed by the magnetic resistance members 50 is larger than the opening of the permanent magnet structure member 22 and completely corresponds to the opening. In each air-gap subspace 31 formed in this case, the fluid magnetizer 40 may fill all air-gap subspaces 31, or the fluid magnetizer 40 may be selectively filled in the corresponding air-gap subspace 31. For example, fluid magnetizers 40 are filled into corresponding air gap subspaces 31 at intervals. Of course, the number of the magnetic blocking members 50 between the first permanent magnets 221 of the two permanent magnet structural members 22 is not limited, and one or more may be provided.

Specifically, referring to fig. 3, in another embodiment, each magnetic resistance member 50 is located at an end of one of the first permanent magnets 221 of the permanent magnet structural member 22, and it can be understood that the magnetic resistance member 50 is located at an end of one of the first permanent magnets 221 of the permanent magnet structural member 22 facing the stator main body 11, so that the air gap sub-space 31 is formed larger than the opening formed by the two first permanent magnets 221 of the permanent magnet structural member 22, and similarly, the filling of the fluid magnetizer 40 in the corresponding air gap sub-space 31 can also serve the purpose of magnetic conduction. Or, each magnetic resistance member 50 is located at the end of the two first permanent magnets 221 of the permanent magnet structural member 22, it can be understood that the two magnetic resistance members 50 are respectively disposed at the end of the two first permanent magnets 221 of the current permanent magnet structure facing the stator main body 11, so that the formed air gap subspace 31 is completely matched with the opening formed by the two first permanent magnets 221 of the permanent magnet structural member 22, at this time, the fluid magnetizer 40 is filled in the air gap subspace 31, and no magnetic flux leakage or magnetic flux leakage in the magnetic circuit is reduced. Furthermore, in the present embodiment, each air gap subspace 31 is divided into a first air gap subspace corresponding to the opening of the permanent magnet structure 22 and a second air gap subspace located at the gap between two adjacent permanent magnet structure 22, so that the fluid magnetizer 40 can be selected as follows when filling: filling all the first air gap subspaces; or, filling part of the first air gap subspace; or all the first air gap subspaces and all the second air gap subspaces are filled; or all the first air gap sub-spaces and part of the second air gap sub-spaces are filled; or, filling part of the first air gap subspace and all the second air gap subspaces; or, filling part of the first air gap subspace and part of the second air gap subspace.

Referring to fig. 4, in another embodiment, the stator portion 10 includes a stator body 11, the rotor portion 20 includes a rotor body 21 and a plurality of protruding structures 23 disposed on an outer side of the rotor body 21, and optionally, the protruding structures 23 are disposed on the outer side of the rotor body 21 at equal intervals with the rotor body 21 as a central axis. An air gap space 30 is formed between the stator body 11 and the rotor body 21 and each of the boss structures 23. In the present embodiment, the synchronous motor is a synchronous reluctance motor, and is different from a synchronous permanent magnet motor in that the torque of the synchronous reluctance motor needs to depend on the protruding structure of the rotor portion 20, that is, the rotor body 21 of the rotor portion 20 is a non-magnetic rotor body 21, and is made of a non-magnetic metal or non-metal material, for example. Meanwhile, the air gap space 30 is filled with the fluid magnetizer 40, the magnetic field formed by the fluid magnetizer 40 interacts with the magnetic field of the energized stator portion 10, and the acting force is formed to push one or more of the convex structures 23, so that the whole rotor portion 20 rotates around the shaft relative to the stator portion 10.

Specifically, referring to fig. 4, the air gap space 30 is a cavity formed between two adjacent protruding structures 23, and the fluid magnetizer 40 is filled in the cavity. It is understood that the cavities are grooves extending in the axial direction of the rotor body 21 and communicating both end portions of the rotor body 21, or the cavities are grooves extending in the axial direction of the rotor body 21 and closed.

Specifically, referring to fig. 1 and 4, the stator portion 10 further includes a plurality of windings 12 wound on the stator body 11. It will be appreciated that each winding 12 is electrically connected to an external power source, and in the energized state, the windings 12 form a magnetic field that interacts with the rotor portion 20.

In one embodiment, the synchronous motor of the present application is an internal rotor motor, and as shown in fig. 1, the stator portion 10 is sleeved outside the rotor portion 20. Of course, the synchronous motor of the present application may also be an external rotor motor, that is, the rotor portion 20 is sleeved outside the stator portion 20.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The synchronous motor is characterized by comprising a stator part and a rotor part matched with the stator part, wherein an air gap space is formed between the stator part and the rotor part, and a fluid magnetizer is filled in the air gap space.

2. The synchronous machine according to claim 1, wherein the stator part comprises a stator main body, the rotor part comprises a rotor main body and a plurality of permanent magnet structural members, the rotor main body is provided with a plurality of mounting grooves matched with the contour of the permanent magnet structural members, each permanent magnet structural member is mounted in the corresponding mounting groove, and the magnetic poles of two adjacent permanent magnet structural members are opposite.

3. The synchronous machine according to claim 2, wherein the permanent magnet structure comprises two first permanent magnets with opposite ends, and an included angle between the two first permanent magnets is gradually reduced along the direction of the notch of the mounting groove, or the included angle between the two first permanent magnets is gradually increased along the direction of the notch of the mounting groove.

4. The synchronous machine of claim 3, wherein the permanent magnet structure further comprises a second permanent magnet for connecting the other end of the two first permanent magnets, and the second permanent magnet and the two first permanent magnets form a U-shaped permanent magnet structure surrounded on the cross section of the rotor body.

5. The synchronous machine according to claim 2, wherein the permanent magnet structure comprises two first permanent magnets with one end abutting and the other end deviating, and an included angle between the two first permanent magnets is gradually increased along the direction of the notch of the mounting groove.

6. The synchronous machine according to any of claims 3 to 5, wherein a plurality of magnetic resistance members are arranged at intervals in the air gap space, and each magnetic resistance member is arranged on one side of the stator main body facing the rotor main body; or, each of the magnetic resistance pieces is arranged on one side of the rotor main body facing the stator main body, the magnetic resistance pieces separate the air gap space to form a plurality of independent air gap subspaces, and the fluid magnetizer is filled in the air gap subspaces.

7. The synchronous machine of claim 6, wherein each of the reluctance members is located between the first permanent magnets of two adjacent permanent magnet structures.

8. The synchronous machine of claim 6, wherein each of the reluctance members is located at an end of one of the first permanent magnets of the permanent magnet structure; or each magnetism resistance part is positioned at the end parts of the two first permanent magnets of the permanent magnet structural part.

9. The synchronous machine of claim 1, wherein the stator portion includes a stator body, the rotor portion includes a rotor body and a plurality of raised structures disposed on an exterior side of the rotor body, the stator body and the rotor body and each of the raised structures forming the air gap space therebetween.

10. The synchronous machine of claim 9, wherein the rotor body is a non-magnetic rotor body.

11. The synchronous machine of claim 9, wherein the air gap space is a cavity formed between two adjacent raised structures, and the fluid magnetizer is filled in the cavity.

12. The synchronous machine of claim 2 or 9, wherein the stator portion further comprises a plurality of windings wound on the stator body.