KR101745963B1

KR101745963B1 - Synchronous reluctance motor

Info

Publication number: KR101745963B1
Application number: KR1020150121932A
Authority: KR
Inventors: 이연택; 홍현석; 유회총; 정태철; 정년기; 이주
Original assignee: 주식회사 삼양감속기; 한양대학교 산학협력단
Priority date: 2015-08-28
Filing date: 2015-08-28
Publication date: 2017-06-12
Also published as: KR20170027889A

Abstract

According to the synchronous reluctance motor of the present invention, in the structure of a rotor for increasing the output density of an electric motor in a three-phase four-pole synchronous reluctance motor, the rotor is formed by forming a metal thin plate into a shape of a circular plate Wherein a plurality of electric steel sheets manufactured by punching are stacked on a front surface of the electric steel plate and a segment and a magnetic flux barrier are alternately arranged so as to allow a magnetic flux generated by the stator to flow, The magnetic flux barrier is arranged in the same manner in each of the first, second, and third quadrants divided into four quadrants at the center of the electric steel sheet.
As described above, according to the present invention, it is possible to improve the output density by reducing the occurrence of leakage magnetic flux, reduce the amount of expensive permanent magnets, and improve the output density of the motor by using the non- A synchronous reluctance motor can be provided.

Description

[0001] Synchronous reluctance motor [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synchronous reluctance motor, and more particularly, to a synchronous reluctance motor capable of improving the output density by reducing the generation of leakage flux of the rotor.

Generally, Synchronous Reluctance Motor (SynRM) has not been widely used due to its low efficiency and low output characteristics compared to permanent magnet type motors. Recently, with the development of power electronic devices and circuit technologies, .

Since the rotor of the synchronous reluctance motor has a simple structure without a winding, it is suitable for a place where the operation is required for a long time because the trouble is small and reliability is high, and maintenance is easy.

A synchronous reluctance motor is a motor that uses a principle in which a rotational force is generated by a change in magnetoresistance due to rotation of a rotor. The rotor includes a core in which a plurality of steel sheet sheets are stacked, and several magnetic flux barriers are formed in the core.

When the rotor is started, the flow of the magnetic flux is blocked by the magnetic flux barrier, and the magnetoresistance between the magnetic flux barrier side (i.e., the q-axis) and the respective magnetic flux barrier groups (i.e., the d-axis) Reluctance torque is generated by the difference in magnetoresistance. Since the reluctance torque is synchronized with the magnetic flux of the stator, the rotor is rotated at the synchronous speed by the reluctance torque.

When the stator winding of the synchronous reluctance motor is not a conventional distributed winding type but a concentrated winding type, the cost of manufacturing the stator is reduced because the number of slots is small, and the winding work in manufacturing is simplified. In addition, compared with the distributed linear type, the concentrated winding type has a relatively large slot area and reduces the amount of coils protruding out of the stator, thereby reducing copper loss.

However, when the winding method of the synchronous reluctance motor is a concentrated winding type, problems such as an increase in torque ripple occur. Therefore, it is very important to design the stator and the rotor considering the influence of the design variables on the design variables and the design parameters affecting the magnitude of the torque ripple when designing the synchronous reluctance motor of concentrated winding type Do.

In addition, the synchronous reluctance motor is manufactured by punching each steel sheet with a die or the like, and then laminated on the rotor shaft. The synchronous reluctance motor has advantages of being easy to manufacture and being suitable for mass production. However, There is a problem that a leakage magnetic flux is generated and the output density is reduced.

Korean Registered Patent Publication No. 10-0709296

SUMMARY OF THE INVENTION It is an object of the present invention which is devised to solve the problems as described above, and it is an object of the present invention to provide a magnetic flux barrier structure in which the ends of the magnetic flux barrier are formed only in the odd- The output density can be improved by reducing the generation of leakage magnetic flux, the amount of expensive permanent magnets can be reduced, and the output density of the motor can be reduced by using the non- So as to provide a synchronous reluctance motor capable of improving the motor efficiency.

According to the synchronous reluctance motor of the present invention for achieving the above object, in a structure of a rotor for increasing the output density of an electric motor in a three-phase four pole synchronous reluctance motor, A plurality of electric steel plates formed by punching a metal plate to form a shape of a circular plate, and a segment and a magnetic flux barrier are formed on the front surface of the electrical steel plate so that a magnetic flux generated by the stator flows. And the segment and the magnetic flux barrier are arranged in the same manner in the first equal part, the second equal part and the third equal part divided into four equal parts by 90 degrees from the center of the electric steel sheet.

And the magnetic flux barrier is formed in at least two portions having different radii and being curved and protruding toward the center of the electrical steel plate in each of the equal portions, Wherein a magnetic flux barrier having a smaller radius toward the outer side from the center of the electric steel plate is disposed apart from the center of the electric steel sheet by a certain distance, A bridge is formed which divides the barrier into two to improve the rigidity of the magnetic flux barrier.

A rib is formed at an end of any one of the plurality of magnetic flux barriers so as to be spaced apart from the outer circumferential surface of the electric steel plate so that the outer peripheral surface of the electric steel plate and the end of the magnetic flux barrier are spaced apart. A leakage magnetic flux preventing portion connected to the outer circumferential surface of the electric steel plate is formed at an end of another magnetic flux barrier adjacent to one magnetic flux barrier to prevent leakage of the magnetic flux.

And the leakage and flux blocking portions are alternately formed from the inner side to the outer side of the plurality of magnetic flux barriers. When the rib is formed on one side with respect to the bridge, a leakage flux preventing portion is formed on the other side, At the end of the magnetic flux barrier formed on the outermost side of the barriers, leakage magnetic flux blocking portions are formed, and are formed on the ends of the magnetic flux barriers on both sides with respect to the bridge.

The plurality of electrical steel sheets are stacked such that the respective electrical steel sheets are rotated in one direction by 90 degrees with respect to the central axis of the electrical steel sheet from the upper side to the lower side or from the lower side to the upper side.

When the electrical steel sheet is divided into quarters, the first, second and third quadrants of the electrical steel sheet are shifted toward one side rotated about the center axis of the electrical steel sheet, The first and second halves are symmetrical with respect to the first and third halves and the second halves and the third halves are symmetrical between the second halves and the third halves and the third halves between the third and fourth halves And the fourth quadrant are symmetrical, and the fourth quadrant and the first quadrant are symmetric with respect to the fourth quadrant and the first quadrant.

As described above, according to the present invention, it is possible to improve the output density by reducing the occurrence of leakage magnetic flux, reduce the amount of expensive permanent magnets, and improve the output density of the motor by using the non- A synchronous reluctance motor can be provided.

1 is a perspective view illustrating a synchronous reluctance motor according to a preferred embodiment of the present invention.
2 is a plan view showing a synchronous reluctance motor according to a preferred embodiment of the present invention.
3 is a perspective view illustrating a rotor of a synchronous reluctance motor according to a preferred embodiment of the present invention.
4 is a graph showing output test results of a synchronous reluctance motor according to a preferred embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, the present invention will be described with reference to the drawings for explaining a synchronous reluctance motor according to embodiments of the present invention.

The present invention relates to a structure of a rotor for increasing the output density of a motor in a three-phase four-pole synchronous reluctance motor.

FIG. 1 is a perspective view of a synchronous reluctance motor according to a preferred embodiment of the present invention, FIG. 2 is a plan view of a synchronous reluctance motor according to a preferred embodiment of the present invention, FIG. 3 is a cross- Fig. 2 is a perspective view showing a rotor of a synchronous reluctance motor according to the present invention;

1 to 3, the rotor 20 is formed by laminating a plurality of electric steel plates manufactured by punching a metal thin plate into a shape of a circular plate with a metal mold.

A segment 21 and a magnetic flux barrier 22 are alternately arranged on the front surface of the electrical steel sheet so that the magnetic flux generated by the stator 10 can flow.

At this time, the segment 21 and the magnetic flux barrier 22 are arranged in the same manner in the first, second and third equally divided quadrants at 90 degrees from the center of the electric steel sheet.

In addition, the magnetic flux barrier 22 is formed to be curved so as to protrude toward the center of the electric steel plate, and has at least two different radii.

The segments are formed between the magnetic flux barriers 22 as magnetic flux barriers 22 whose radius decreases from the center to the outside of the electric steel plate are arranged at a certain distance apart.

A bridge is provided on the front surface of the electrical steel plate for improving the rigidity of the magnetic flux barrier 22 by bisecting the magnetic flux barrier 22 across the center of the electric steel plate and the magnetic flux barrier 22 and the center of the segment 21 .

For example, the bridge 23 is formed so as to correspond to an imaginary line position connecting the centers of the electric steel plates with the first equal part at the center of the first equal part, that is, 45 degrees.

At one end of each of the plurality of magnetic flux barriers 22, a rib 24 is formed so as to be spaced apart from the outer circumferential surface of the electric steel plate and between the outer peripheral surface of the electric steel plate and the end of the magnetic flux barrier.

At this time, since the lip 24 generates the leakage magnetic flux, the magnetic flux density is lowered.

Therefore, in order to increase the magnetic flux density, the ribs 24 should be eliminated as much as possible, but this is preferably determined in consideration of the stiffness of the rotor.

Thereby, at the end of another magnetic flux barrier 22 adjacent to one of the magnetic flux barriers 22 formed with the ribs 24, a leakage magnetic flux preventing portion 25 connected to the outer peripheral surface of the electric steel plate is formed, prevent.

At this time, the lip 24 and the leakage magnetic flux preventing portion 25 are alternately formed in a plurality of magnetic flux barriers 22 from the inside to the outside of the electric steel plate.

In addition, when the ribs 24 are formed on one side with respect to the bridge 23, the leakage flux preventing portions 25 are formed on the other side

In other words, at the ends of the magnetic flux barriers 22 formed on the outermost side of the plurality of magnetic flux barriers 22, leak magnetic flux preventing portions 25 are formed. On the ends of the magnetic flux barriers 22 on both sides of the bridge 23, Is preferably formed.

FIG. 2 (a) is a plan view showing a conventional synchronous reluctance motor, and FIG. 2 (b) is a plan view showing a synchronous reluctance motor of the present invention.

2 (a), the conventional rib 24 is formed to be spaced apart from the outer circumferential surface of the electrical steel sheet for each magnetic flux barrier 22. The problem of the output density of the rib 24 being such that leakage magnetic flux is generated 2 (b), the leakage magnetic flux preventive portion 25 is formed at each end of the magnetic flux barrier which is alternately arranged from the inner side to the outer side of the electric steel sheet among the plurality of magnetic flux barriers, ) Portion is removed from the stiffness so as to reduce the leakage magnetic flux, thereby improving the output density of the motor.

On the other hand, each of the plurality of electrical steel sheets is stacked such that the respective electrical steel sheets are rotated in one direction by 90 degrees with respect to the central axis of the electrical steel sheet from the upper side to the lower side or from the lower side to the upper side.

When the electric steel sheet is divided into quarters, the first, second and third quasi-equilibrium ratios of the first and second quasi- The first and second equals are symmetrical, and the second and third equals are symmetrical with respect to the second and third equations, and the third equals and the third equals between the third and fourth equations The fourth quadrant is symmetrical, and the fourth quadrant and the first quadrant are symmetrical between the fourth quadrant and the first quadrant.

That is, since the magnetic flux barrier 22 should not be turned, one electric steel plate of the rotor 20 is rotated and stacked at an angle of 360 / pole.

That is, since the present invention has four poles, it is rotated by 90 degrees and laminated.

4 is a graph showing output test results of a synchronous reluctance motor according to a preferred embodiment of the present invention.

Referring to FIG. 4, the synchronous reluctance motor according to the present invention is an experiment for comparing output characteristics with a conventional motor.

At this time, in the conventional electric motor, the ribs 24 are formed for each magnetic flux barrier 22, and the electric steel plates of the rotor 20 are stacked so as to correspond to each other.

As a result, the torque characteristics of the synchronous reluctance motor according to the present invention were 18.18 [Nm], and the conventional motor was 17.74 [Nm].

That is, it can be seen that the synchronous reluctance motor according to the present invention has a torque of about 0.44 [Nm] higher than that of the conventional motor.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the foregoing detailed description, and all changes or modifications derived from the meaning and scope of the claims and the equivalents thereof are included in the scope of the present invention Should be interpreted.

10: stator 20: rotor
21: Segment 22: flux barrier
23: Bridge 24: Lip
25: Leakage flux preventive section

Claims

In a three-phase four-pole synchronous reluctance motor having a rotor structure for increasing the output density of a motor,
The rotor is formed by laminating a plurality of electrical steel plates manufactured by punching a metal thin plate into a shape of a circular plate with a metal mold.
In order to improve the stiffness of the rotor by changing the segments, the magnetic flux barrier, the lip, the leakage magnetic flux preventing portion and the lamination structure,
A plurality of segments and magnetic flux barriers are alternately arranged on the front surface of the electrical steel sheet so that the magnetic flux generated by the stator flows,
The segment and the magnetic flux barrier are arranged in the same manner in the first, second, and third equal halves divided by 90 degrees at the center of the electric steel sheet,
Wherein the magnetic flux barrier is disposed in each of the equal halves and is curved so as to be convexly protruded toward the center of the electric steel plate and has at least two or more different radii,
The segment is formed between the magnetic flux barriers as the magnetic flux barriers whose radii become smaller toward the outer side from the center of the electric steel plate are arranged at a certain distance apart,
A bridge is formed which divides the magnetic flux barrier across the center of the electric steel plate and the magnetic flux barrier and the center of the segment to improve the stiffness of the magnetic flux barrier,
Wherein a rib is formed at an end of one of the plurality of magnetic flux barriers so as to be spaced apart from an outer circumferential surface of the electric steel plate and spaced apart from an outer circumferential surface of the electric steel plate and an end of the magnetic flux barrier,
A magnetic flux leakage preventing portion connected to an outer circumferential surface of the electric steel plate is formed at an end of another magnetic flux barrier adjacent to any one of the magnetic flux barriers to prevent leakage of the magnetic flux,
The lip and the leakage magnetic flux preventing portion are alternately formed on the plurality of magnetic flux barriers,
When a lip is formed on one side with respect to the bridge, a leakage magnetic flux blocking portion is formed on the other side,
A leakage magnetic flux blocking portion is formed at an end of a magnetic flux barrier formed at the outermost one of the plurality of magnetic flux barriers, and is formed at each end of the magnetic flux barrier on both sides of the bridge
In the structure of the segment, the magnetic flux barrier, the lip and the leakage magnetic flux preventing portion
When the electrical steel sheet is divided into quarters, the first, second, and third quadrants of the electrical steel sheet are divided into first quadrants, second quadrants, and third quadrants, The first and second equals are symmetrical, and the second and third equals are symmetrical with respect to the second and third equations, and the third equals and the third equals between the third and fourth equations The fourth equal part is symmetrical, and the fourth equal part and the first equal part are formed to be symmetrical with respect to the fourth equal part and the first equal part
The plurality of electric steel plates are stacked such that the respective electric steel plates are rotated in one direction by 90 degrees with respect to the center axis of the electric steel plate as they are shifted from the upper side to the lower side or from the lower side to the upper side, And increases the output density of the electric motor while improving the stiffness of the motor.

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