CN112688528B

CN112688528B - Multi-harmonic excitation type arc permanent magnet synchronous motor

Info

Publication number: CN112688528B
Application number: CN202011565618.4A
Authority: CN
Inventors: 房淑华; 盘真保
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2020-12-25
Filing date: 2020-12-25
Publication date: 2021-09-24
Anticipated expiration: 2040-12-25
Also published as: CN112688528A

Abstract

The utility model discloses a multi-harmonic excitation type arc permanent magnet synchronous motor, which comprises a rotor and a stator; the rotor consists of three parts, namely a rotor yoke, rotor teeth and a rotating shaft; the stator part consists of three stator units, wherein each stator unit consists of a stator yoke, stator teeth, an armature winding, auxiliary teeth, a permanent magnet and a magnetic adjusting block; the three stator units are uniformly distributed outside the rotor part along the circumference; each stator unit and each rotor form an arc line permanent magnet unit motor. An array consisting of permanent magnets and magnetic adjusting blocks is attached to the top surface of each stator unit, and the array is distributed in a 'iron-magnetic north pole-magnetic south pole-iron-magnetic south pole-magnetic north pole'. The magnetic field generated by such an array is modulated by the rotor teeth, so that a plurality of working harmonics exist in the air gap of the motor, and all the working harmonics participate in the contribution of torque, so that the motor has the advantage of high torque density.

Description

Multi-harmonic excitation type arc permanent magnet synchronous motor

Technical Field

The disclosure belongs to the field of permanent magnet synchronous motors, and particularly relates to a multi-harmonic excitation type arc permanent magnet synchronous motor.

Background

The large-caliber astronomical telescope has a huge frame, the weight of the large-caliber astronomical telescope reaches hundreds to thousands of tons, and the defects of reverse clearance, poor dynamic performance, complex mechanical structure, low control precision and the like exist by adopting traditional transmission modes such as worm gear transmission, gear transmission and the like. With the progress of scientific technology, a direct-drive mode adopting a spliced arc motor is considered to be a solution with good prospect. Such as the very large telescope of southern astronomical observatories in europe (8.2m), the large canary telescope of spain (10.4m) and the like, have successfully used the direct drive mode of the spliced arc motor. The transmission mode is also deeply researched by scientific research units such as national institute of astronomy optics and institute of photoelectric technology of the Chinese academy. Chinese patent (patent number: CN2015102840353.7) discloses a three-dimensional air gap Halbach permanent magnet arc-shaped motor for an astronomical telescope and a control method thereof, wherein a rotor of the motor structure is distributed with Halbach permanent magnet type permanent magnets, and a stator adopts a C-shaped structure to form a three-dimensional air gap finally, so that the torque density is effectively improved, and meanwhile, the Halbach structure can inhibit torque pulsation. Chinese patent (application number: CN201810159260.1) discloses an asymmetric double three-phase arc permanent magnet synchronous motor, wherein a stator of the motor adopts two different stator modules to form an asymmetric arc structure; the rotor is distributed by adopting built-in V-shaped permanent magnets, the magnetic concentration effect is strong, and the main flux can be effectively improved, so that the asymmetric double three-phase arc line permanent magnet synchronous motor has higher torque density, lower torque pulsation, good operation stability and good reliability. However, the arc motors all belong to rotor permanent magnet type arc motors, a large number of permanent magnets are positioned on the side of the rotor, and only part of effective permanent magnets participate in the generation of torque in the movement process of the arc motors; most of the permanent magnets are exposed to air and do not participate in the generation of torque. Therefore, the rotor permanent magnet type arc permanent magnet motor has lower permanent magnet utilization rate; moreover, because a large number of permanent magnets are positioned on the side of the rotor, the permanent magnet motor has the defect of high manufacturing cost, and is particularly obvious on a large-caliber arc motor. Therefore, the arc motor for the large-caliber astronomical telescope has many scientific problems to be solved urgently, such as further improvement of motor torque density and permanent magnet utilization rate, further reduction of manufacturing cost and the like.

Disclosure of Invention

Aiming at the defects of the prior art, the purpose of the present disclosure is to provide a multi-harmonic excitation type arc permanent magnet synchronous motor, which solves the problem that only part of effective permanent magnets participate in the generation of torque in the motor motion process in the prior art.

The purpose of the disclosure can be realized by the following technical scheme:

a multi-harmonic excitation type arc permanent magnet synchronous motor comprises a rotor and a stator; the rotor consists of three parts, namely a rotor yoke, rotor teeth and a rotating shaft; the stator part consists of three stator units, wherein each stator unit consists of a stator yoke, stator teeth, an armature winding, auxiliary teeth, a permanent magnet and a magnetic adjusting block; the three stator units are uniformly distributed outside the rotor part along the circumference; each stator unit and each rotor form an arc line permanent magnet unit motor. An array consisting of permanent magnets and magnetic adjusting blocks is attached to the top surface of each stator unit, and the array is distributed in a 'iron-magnetic north pole-magnetic south pole-iron-magnetic south pole-magnetic north pole'.

As a further preferred scheme, the rotor yoke and the rotor teeth are both formed by pressing silicon steel sheets with good magnetic conductivity, and 55 rotor teeth are uniformly distributed on the whole rotor, so as to form 55 opposite poles.

As a further preferred solution, the stator part consists of three stator units, which are evenly distributed circumferentially outside the rotor.

As a further preferable scheme, the 6 armature windings on the stator unit are wound on the 6 stator teeth in a non-overlapping concentrated winding mode; armature-free windings are arranged on 2 auxiliary teeth on two sides of the stator unit; the armature windings of the three units are connected in series to form a complete three-phase winding.

As a further preferred scheme, the stator yoke, the stator teeth, the auxiliary teeth and the magnetic adjusting blocks of the stator part are all formed by pressing silicon steel sheets with good magnetic conductivity.

As a further preferred scheme, there are two magnetizing directions of the permanent magnet, which are radially outward magnetizing (N pole) and radially inward magnetizing (S pole), respectively; the two permanent magnets are made of neodymium iron boron with high magnetic energy product.

As a further preferable scheme, an array composed of permanent magnets and magnetic adjusting blocks is attached to the top of the stator teeth of the stator unit, and the array composed of the permanent magnets and the magnetic adjusting blocks is distributed in an 'iron-magnetic north pole-magnetic south pole-iron-magnetic south pole-magnetic north pole'.

As a further preferable scheme, in the array formed by the permanent magnets and the magnetic adjusting blocks, the magnetizing directions of adjacent nearest permanent magnets are opposite, the number and the arc length of the two permanent magnets are equal, and 6 permanent magnets are respectively arranged; the magnetic adjusting blocks in the array are of two types, wherein the arc length of the middle magnetic adjusting block is equal to that of the permanent magnet, and the total number of the magnetic adjusting blocks is 5; the arc length of the magnetic adjusting blocks at the two sides is half of that of the middle magnetic adjusting block, and the total number of the magnetic adjusting blocks is 2.

As a further preferred solution, the position between the stator units (III) can be freely moved.

The beneficial effect of this disclosure:

the utilization rate of the motor permanent magnet is improved.

Drawings

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present disclosure, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

Fig. 1 is a schematic view of the overall structure of the motor of the present invention;

FIG. 2 is a schematic view of a rotor of the motor of the present invention;

fig. 3 is a schematic view of a stator unit (III) of the motor of the present invention; (ii) a

FIG. 4 is a linear schematic diagram of an array structure composed of permanent magnets and magnetic blocks;

FIG. 5 is a waveform of air gap flux density generated by an array of "iron-magnetic North-magnetic south-iron-magnetic south-magnetic North" and its harmonic analysis;

FIG. 6 is a waveform of an air gap flux density generated by an array of 'iron-magnetic north pole-magnetic south pole-iron-magnetic south pole-magnetic north pole' modulated by rotor teeth and harmonic analysis thereof.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

As shown in fig. 1-6, a multi-harmonic excitation type arc permanent magnet synchronous motor comprises a rotor part I and a stator part II; the rotor I consists of three parts, namely a rotor yoke 1, rotor teeth 2 and a rotating shaft 3; rotor yoke 1 and rotor tooth 2 are formed by the silicon steel sheet suppression that magnetic conductivity is good, pivot 3 comprises the stainless steel material of non-magnetic conductivity, evenly distributed 55 rotor teeth on the whole rotor, thereby form 55 antipodes, through so design, rotor I only has rotor core to constitute, moved the rotor permanent magnet to the stator side, simple rotor core structure only plays the effect that the magnetic circuit switched on and the magnetic field modulation like this, this rotor simple structure, the robustness is good, the dynamic behavior is fast, and be favorable to the heat dissipation of permanent magnet, be applicable to the drive control of heavy-calibre astronomical telescope.

The stator unit III is composed of a stator yoke 4, stator teeth 5, an armature winding 6, auxiliary teeth 7, permanent magnets 8 and a magnetic adjusting block 9; the three stator units III are distributed outside the rotor part I along the circumference; the armature windings of all phases of the three stator units III are connected in series to form a complete three-phase winding finally; the positions of the three stator units III can be freely moved, and the optimal positions of the three stator units III can be finally determined according to the symmetry and balance of three-phase induced electromotive force of the whole motor and the minimum peak-to-peak value of no-load cogging torque.

Furthermore, three stator unit III is along circumference evenly distributed, and the winding of three stator unit III passes through the cross connection mode, through so design, can solve the motor well because of the torque ripple that the limit effect arouses, and the auxiliary teeth 7 of stator unit III both sides plays the effect of guide magnetic circuit circulation simultaneously, has effectively reduced the magnetic field sudden change that the limit effect arouses to further reduce torque ripple.

In some disclosures, the stator unit III has 6

stator teeth

5 and 2 auxiliary teeth 7; 6 non-overlapping concentrated armature windings 6 are wound on 6 stator teeth 5, and compared with distributed windings, the concentrated armature windings 6 have shorter end length, so that copper loss of the windings can be effectively reduced, and finally the output efficiency of the whole motor is improved. The auxiliary teeth 7 positioned on two sides of the stator unit III play a role in guiding the magnetic field to flow along a path with small magnetic resistance, so that the magnetic field mutation effect caused by the opening and the closing of the iron core is effectively inhibited, and the torque pulsation is effectively inhibited. In the motor provided by the invention, each stator unit III and the rotor form an arc permanent magnet unit motor with 6 stator slots and 11 rotor poles matched with the pole slots, and further, the concentrated winding is convenient to process and wind, so that the modular development of the whole motor is realized.

In some disclosures, the permanent magnets 8 and the magnetic regulating blocks 9 form an array structure, in the array, the permanent magnets 8 and the magnetic regulating blocks 9 are alternately arranged, and finally an array distributed in a 'iron-magnetic north pole-magnetic south pole-iron-magnetic south pole-magnetic north pole' mode is formed;

in some disclosures, the permanent magnet 8 is installed on the stator unit III, compared with the existing rotor permanent magnet type arc permanent magnet synchronous motor, the permanent magnet synchronous motor has the advantages of higher permanent magnet utilization rate, great saving of the permanent magnet consumption of the whole motor, and reduction of the manufacturing cost of the whole motor, and is particularly obvious in the structure of a large-caliber arc permanent magnet motor.

In some disclosures, the permanent magnets 8 and the magnetic regulating blocks 9 form an array with distributed 'iron-magnetic north pole-magnetic south pole-iron-magnetic south pole-magnetic north pole', the magnetizing directions of adjacent nearest permanent magnets are opposite, the number and the arc length of the two permanent magnets are equal, and 6 permanent magnets are arranged in each array; the magnetic adjusting blocks in the array are of two types, wherein the arc length of the middle magnetic adjusting block is equal to that of the permanent magnet, and the total number of the magnetic adjusting blocks is 5; the arc length of the magnetic adjusting blocks at the two sides is half of that of the middle magnetic adjusting block, and the total number of the magnetic adjusting blocks is 2. The array enables the air gap magnetic field excited by the arc motor to have multiple harmonics, mainly 3, 9 and 15 harmonics;

with the rotation of the rotor, under the modulation of the rotor teeth, new harmonics of the air

gap flux density

2, 8 and 14 are modulated besides the original harmonics of the

flux density

3, 9 and 15, as shown in fig. 6; the air gap flux density harmonics are working harmonics, interact with an armature magnetic field generated by an armature winding to participate in electromechanical energy conversion, and further generate larger output torque. In addition, the permanent magnet material of the arc motor adopts neodymium iron boron with high magnetic energy product, can generate larger magnetic flux, and can further realize high torque output.

Furthermore, the technical scheme of the disclosure is also applicable to the outer rotor and inner stator multi-harmonic excitation type arc permanent magnet synchronous motor, and the above description is only a preferred embodiment of the disclosure.

Principle of operation

The permanent magnet is placed on the side of the stator, so that the utilization rate of the permanent magnet is effectively improved, the using amount of the permanent magnet is greatly saved, and the manufacturing cost is reduced, so that the multi-harmonic excitation type arc permanent magnet synchronous motor disclosed by the invention has higher torque density and lower torque pulsation, and can be applied to low-speed and high-torque direct-drive occasions such as large-caliber astronomical telescopes.

In the description herein, references to the description of "one embodiment," "an example," "a specific example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the disclosure. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing illustrates and describes the general principles, principal features, and advantages of the present disclosure. It will be understood by those skilled in the art that the present disclosure is not limited to the embodiments described above, which are presented solely for purposes of illustrating the principles of the disclosure, and that various changes and modifications may be made to the disclosure without departing from the spirit and scope of the disclosure, which is intended to be covered by the claims.

Claims

1. A multi-harmonic excitation type arc permanent magnet synchronous motor comprises a rotor (I) and a stator (II), and is characterized in that the stator (II) comprises a plurality of stator units (III), each stator unit (III) comprises a stator yoke (4) and stator teeth (5), a plurality of stator teeth (5) are arranged on the stator yoke (4), the stator units (III) are uniformly distributed on a rotor part (I) along the circumference, an array consisting of permanent magnets (8) and magnet adjusting blocks (9) is pasted on the stator teeth (5), the top of each stator tooth of each stator unit (III) is pasted with an array of the permanent magnets (8) and the magnet adjusting blocks (9), the permanent magnets and the magnet adjusting block arrays are distributed in an ' iron-magnetic south pole-magnetic north pole ', and the magnetic north pole ' direction in the array of the permanent magnets (8) and the magnet adjusting blocks (9), the magnetizing directions of the adjacent permanent magnets (8) are opposite, the two permanent magnets (8) are equal in number and arc length and respectively have 6 blocks; the magnetic adjusting blocks (9) in the array are of two types, wherein the arc length of the middle magnetic adjusting block (9) is equal to that of the permanent magnet (8), and the total number of the magnetic adjusting blocks (9) is 5; the arc length of the magnetic adjusting blocks (9) at the two sides is half of that of the middle magnetic adjusting block (9), and the total number of the magnetic adjusting blocks (9) is 2.

2. The multi-harmonic excitation type arc permanent magnet synchronous motor according to claim 1, wherein the rotor part (I) comprises three parts of a rotor yoke (1), rotor teeth (2) and a rotating shaft (3), the rotating shaft (3) is provided with the rotor yoke (2), and the rotor yoke (2) is provided with a plurality of uniformly distributed rotor teeth (2).

3. A multiple harmonic excitation type arc permanent magnet synchronous motor according to claim 1, wherein the stator (II) is composed of three stator units (III) which are uniformly distributed on the outside of the rotor (I) along the circumference.

4. A multiple harmonic excitation type arc permanent magnet synchronous motor according to claim 1, wherein the stator teeth (5) are provided with armature windings (6), and the armature windings (6) are wound on the stator teeth (5) in a non-overlapping concentrated winding manner.

5. A multiple harmonic excitation type arc permanent magnet synchronous motor according to claim 1, wherein 6 stator teeth (5) are provided on the stator yoke (4).

6. A multi-harmonic excitation type arc permanent magnet synchronous motor according to claim 1, wherein auxiliary teeth (7) are arranged on both sides of the stator unit (III), and armature windings of each phase of the stator unit (III) are connected in series to form a complete three-phase winding.

7. A multiple harmonic excitation type arc permanent magnet synchronous motor according to claim 1, wherein the permanent magnets (8) are magnetized in two directions, namely radially outward magnetization (N pole) and radially inward magnetization (S pole).

8. Multiple harmonic excitation arc permanent magnet synchronous machine according to claim 1, characterized in that the position between the stator units (III) is freely movable.