KR100570221B1 - Motor for reducing torque ripple and rising average torque - Google Patents

Abstract

The present invention relates to a motor for reducing torque ripple and increasing an average torque, and more particularly, a motor including a stator having a winding part and a rotor which rotates about an axis while an electric current is supplied to the winding part. The rotor has a plurality of rotor poles toward the outside and the stator has a plurality of stator poles toward the inside, the rotor pole has a trapezoidal shape, the stator pole has a rectangular shape corresponding to the rotor pole It is done.

Motor, rotor, stator, rotor poles, stator poles.

Description

Motor for reducing torque ripple and rising average torque

1 is a cross-sectional view schematically showing the structure of a rotor and a stator in a motor according to the prior art,

2 is a graph illustrating a torque ripple in a motor having the structure of FIG. 1;

3 is a cross-sectional view of a first embodiment schematically showing the structure of a rotor and a stator in a motor according to the present invention;

4 is a cross-sectional view of a second embodiment schematically showing the structure of a rotor and a stator in a motor according to the present invention;

5 is a graph illustrating a torque ripple in a motor having the structure of FIG. 4.

Explanation of symbols on the main parts of the drawing

10; Switched reluctance motor 20; Stator

21; Stator pole 30; Rotor

31; Rotor pole 40; shaft

50; Winding

The present invention relates to a motor, and more particularly to a motor for reducing torque ripple and increasing average torque.

In general, a motor is used to drive a machine or equipment by using rotational force. Motors that are currently in the spotlight include Switched Reluctance Motors and Brushless DC Motors.

In particular, among these motors, a switched reluctance motor is currently being studied as a next-generation motor, and is a motor that obtains a driving force by converting a change in angle according to the rotation of the rotor into a change in magnetoresistance, that is, a reluctance. These switched reluctance motors are used in various fields, such as home and industrial.

1 is a cross-sectional view showing the structure of a rotor (rotor: 3, also referred to as 'rotor') and a stator (2, also referred to as 'stator') of the switched reluctance motor according to the prior art.

As shown in Fig. 1, the conventional switched reluctance motor 1 is a 6/4 system, that is, a reluctance motor having six stator poles 4 and four rotor poles 5, and the stator 2 The rotor 3 rotates with respect to

Specifically, the stator 2 is provided at the outermost side of the motor 1, and six stator poles 4 are arranged at regular intervals toward the shaft 6 of the center portion. Between the stator poles 4 is provided with a separate winding portion 7 for receiving a current to generate a magnetic force. The rotor 3 has four rotor poles 5 arranged at regular intervals towards the stator 2 with respect to the shaft 6 in the center.

Here, the rotor poles 5 and the stator poles 4 are spaced at minute intervals so that the rotor 3 does not contact when rotating. In general, the rotor poles 5 and the stator poles 4 have a rectangular shape as a whole.

2 is a graph illustrating torque ripple of a switched reluctance motor according to the related art. This is the torque ripple calculated through the finite element method, which is a numerical method, and the progressive quadratic response surface method, which is one of the optimization algorithms. Torque ripple calculation conditions in Figure 2 are shown in Table 1 below.

Item value Item value Rated torque 0.03 (Nm) Stator diameter 100 (mm) Rated voltage 12 (V) Rotor diameter 40 (mm) Speed 2000 (rpm) Shaft diameter 8 (mm) Rated current 1.3 (A) Void length 0.3 (mm) a constant 3 Stacking width 40 (mm) Stator / rotor poles 6/4 Stator York Thickness (A) 6 (mm)

)Stator polar angle (

) 30 ° Rotor York thickness (B) 6 (mm) Core material S18 in electrical steel Turns of one statue 79 turns

), 즉 샤프트(6)의 중앙을 기준으로 한 상기 로터 극(5)의 양 끝단에 이르는 각은 30°이고, 스테이터 극(4)의 극호각(

), 즉 샤프트(6)의 중심을 기준으로 한 상기 스테이터 극(4)의 양 끝단에 이르는 각은 30°이다. 그리고 턴 온각(

)은 10.2°이고, 턴 오프각(

)은 30.1°이다.In addition, the polar angle of the rotor pole (5)

), I.e., the angle reaching both ends of the rotor pole 5 with respect to the center of the shaft 6 is 30 ° and the arc angle of the stator pole 4 (

), I.e. the angle leading to both ends of the stator pole 4 with respect to the center of the shaft 6 is 30 °. And turn on angle (

) Is 10.2 ° and the turn off angle (

) Is 30.1 °.

However, as shown in FIG. 2, the conventional switched reluctance motor 1 has a large torque ripple of about 93.58%, and in the related art, since the torque ripple is large in the related art, There was a problem that severely generated vibrations and noise during rotation.

)과 스테이터 극(4)의 극호각(

)의 비를 조절하여 토크리플을 낮추려는 노력을 하고는 있지만, 별 다른 실효성이 없었다.Recently, the polar angle of the rotor pole (5)

) And the polar angle of the stator pole (4)

While trying to lower the torque ripple by adjusting the ratio of), it was not very effective.

The present invention has been made to solve the above problems, an object of the present invention is to provide a motor that can achieve a torque ripple reduction and an average torque rise by changing the shape of the rotor pole and optimally adjusting the polar angle accordingly. .

According to an aspect of the present invention for achieving the above object, a motor including a stator provided with a winding portion, and a rotor that rotates about an axis while an electric current is supplied to the winding portion, wherein the rotor has a plurality of outward directions. A rotor pole and the stator has a plurality of stator poles inward, the rotor pole has a trapezoidal shape, and the stator pole has a rectangular shape corresponding to the rotor pole, and averages torque ripple reduction. Provides a motor for torque rise.

In addition, when the pole angle of the pole of the stator is 30 °, the pole angle of the pole of the rotor is characterized in that between 30 ° to 50 °.

The rotor poles are four and the stator poles are six.

Hereinafter, a preferred embodiment of a motor for reducing torque ripple and increasing average torque according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view of the first embodiment schematically showing the structure of the rotor and the stator in the motor according to the invention, Figure 4 is a cross-sectional view of the second embodiment schematically showing the structure of the rotor and the stator in the motor according to the invention 5 is a graph illustrating torque ripples in the motor having the structure of FIG. 4.

First, as shown in FIG. 2 and FIG. 3, the motor 10 for reducing torque ripple and increasing the average torque according to the present invention is provided at the shaft 40 at the center and the outside of the shaft 40. A rotor 30 having a plurality of rotor poles 31 as an outer circumferential surface, a stator 20 provided outside the rotor 30 and having a plurality of stator poles 21 toward the rotor 30, and It is provided between the stator poles 21 and the winding unit 50 receives a current to generate a magnetic force. In the motor 10 having such a configuration, the magnetic force is generated in the winding unit 50 and the rotor 3 rotates with respect to the stator 2.

Particularly, in the present invention, the shape of the rotor pole 31 is trapezoidal, and the stator pole 21 has a parallel shape such that the shape of the tip corresponds to the shape of the tip of the rotor pole 31.

Here, it is preferable that there are four rotor poles 31 and six stator poles 20.

1,

2)은 30°내지 50°사이인 것이 바람직하다. 가장 바람직하게는, 스 테이터 극(21)의 극호각(

)이 30°일 경우, 도 2와 같이 로터 극(31)의 극호각(

1)이 38.3°이거나, 도 3과 같이 로터 극(31)의 극호각(

2)이 47.1°인 것이 바람직하다.In addition, when the pole angle of the stator pole 20 is 30 °, the pole angle of the rotor pole 31 (

One,

2) is preferably between 30 ° and 50 °. Most preferably, the polar angle of the stator pole 21 (

) Is 30 °, the polar angle of the rotor pole 31 as shown in Fig.

1) is 38.3 ° or the polar angle of the rotor pole 31 as shown in FIG.

It is preferable that 2) is 47.1 degrees.

As the type of the motor 10 applied to the present invention, a switched reluctance motor and a brushless DC motor are preferable, and more preferably a switched reluctance motor.

This switched reluctance motor is a magnetoresistance (referred to as "reluctance") torque method. More specifically, the switched reluctance motor is a torque method generated by depending on the magnetic structure by exciting only one side of the internal stator or rotor, and is induced by a change in reluctance and excitation energy of the magnetic circuit. Torque is generated when the rotor tries to match the magnetic flux generated by the current flowing through the stator's winding in the direction of decreasing or increasing inductance.

When the rotor poles 31 and the stator poles 21 have the same conditions and shapes as described above, and the polar angles of the rotor poles 31 and the stator poles 21 are the same as the above conditions, torque ripple is reduced. It can significantly reduce and significantly increase the average torque. As described above, the present invention can significantly reduce vibration and noise generated when the rotor rotates by reducing torque ripple and raising average torque.

2), 즉 샤프트(40)의 중앙을 기준으로 한 상기 로터 극(31)의 양 끝단에 이르는 각은 47.1°이고, 스테이터 극(21)의 극호각(

)이 30°인 상태이며, 턴 온각(

)은 0.8°이고, 턴 오프각(

)은 34.2°일 경우, 수치해석 기법인 유한요소법과 최적화 알고리즘의 하나인 프로그래시브 퀘이드레틱 리폰스 설피스 방법(Progressive Quadratic Reponse Surface Method)을 통해 산출된 토크리플은 도 5에 도시된 바와 같다.For example, as shown in FIG. 4 in addition to the conditions of Table 1, the polar angle of the rotor pole 31 (

2), that is, the angle reaching both ends of the rotor pole 31 with respect to the center of the shaft 40 is 47.1 °, and the polar angle of the stator pole 21 (

) Is 30 ° and the turn on angle (

) Is 0.8 ° and the turn off angle (

) Is 34.2 °, the torque ripple calculated by the progressive quadratic response surface method, which is one of the finite element method, which is a numerical method, and an optimization algorithm, is shown in FIG. .

In the graph shown in FIG. 5, the torque ripple was about 7.1%. Unlike the graph of FIG. 2, the torque ripple was maintained almost uniformly, and the torque ripple was considerably reduced. It can be seen that the increase was much higher.

1)은 38.3°이고, 스테이터 극(21)의 극호각(

)이 30°이며, 턴 온각(

)은 0.7°이고, 턴 오프각(

)은 32.4°일 경우, 수치해석 기법인 유한요소법과 최적화 알고리즘의 하나인 공액경사도법(Conjugate Gradient Method)을 통해 산출된 토크리플은 역시 도 5와 거의 유사한 형태의 파형을 얻을 수 있었다. 이 경우 토크리플은 18.81%정도로 나타났다.Although not shown separately in the drawing, the polar angle of the rotor pole 31 as shown in FIG.

1) is 38.3 ° and the polar angle of the stator pole 21 (

) Is 30 ° and the turn-on angle (

) Is 0.7 ° and the turn off angle (

), When 32.4 °, the torque ripple calculated by the finite element method, which is a numerical analysis method, and the conjugate gradient method, which is one of the optimization algorithms, was also able to obtain a waveform almost similar to that of FIG. In this case, the torque ripple was about 18.81%.

Accordingly, as shown in the present invention, the rotor pole 31 has a trapezoidal shape, and the stator pole 21 has a rectangular shape corresponding to the rotor pole 31, and the rotor pole 31 when the pole angle of the stator pole is 30 °. In the case of maintaining a polar angle of 30 ° to 50 °, various numerical solvers show that the present invention can reduce the torque ripple and increase the average torque in comparison with the related art.

The present invention relates to a motor for reducing torque ripple and increasing average torque, wherein the rotor pole has a trapezoidal shape, the stator pole has a rectangular shape corresponding to the rotor pole, and the rotor when the pole angle of the stator pole is 30 °. When the pole angle of the pole is maintained between 30 ° and 50 °, the torque ripple can be significantly reduced and the average torque can be significantly increased as compared with the conventional art. Thus, by reducing the torque ripple and increasing the average torque, There is an excellent effect that can significantly reduce the vibration and noise generated.

Claims (3)

A motor comprising a stator provided with a winding part and a rotor which rotates about an axis while an electric current is supplied to the winding part. The rotor has a plurality of rotor poles toward the outside and the stator has a plurality of stator poles toward the inside, the rotor pole has a trapezoidal shape, the stator pole has a rectangular shape corresponding to the rotor pole A motor for reducing torque ripple and increasing average torque. The motor for reducing torque ripple and increasing average torque according to claim 1, wherein when the pole angle of the pole of the stator is 30 °, the pole angle of the pole of the rotor is between 30 ° and 50 °. 3. The motor for reducing torque ripple and increasing average torque according to claim 1 or 2, wherein the rotor poles are four and the stator poles are six.

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