KR102300921B1 - Improved Radial Force Reduction Switched Reluctance Motor - Google Patents

Abstract

The present invention relates to an improved radial force reduction SRM, and more particularly, to an "improved radial force reduction SRM" for reducing vibration and noise by improving the shape of a rotating magnetic pole to reduce radial force. it's about
The improved radial force reduction SRM according to an embodiment of the present invention includes a stator surrounded by a winding having a plurality of stator poles, and a rotor accommodated inside the stator and having a plurality of rotating poles facing outward. The rotational magnetic pole has a hollow hole portion formed therein in the longitudinal direction, and the hole portion corresponds to 40 to 60% of the length in the longitudinal direction and is equally divided in the longitudinal direction. The second hole is formed to reduce the radial force.
In addition, the first and second hole portions are arranged to be spaced apart from each other by a predetermined distance in the longitudinal direction, and the hole portions are spaced apart from each other by the predetermined distance at both ends in the longitudinal direction.
In addition, the diameter of the hole portion is less than 1/2 of the rotor width.
In addition, the stator has six stator poles, and the rotor has four rotating poles.
Alternatively, the stator has 12 stator poles, and the rotor has 8 rotation poles.

Description

Improved Radial Force Reduction Switched Reluctance Motor

The present invention relates to an improved radial force reduction SRM, and more particularly, to an "improved radial force reduction SRM" for reducing vibration and noise by improving the shape of a rotating magnetic pole to reduce radial force. it's about

In recent years, the demand for electric motors (motors) has increased significantly in various fields such as automobiles, aerospace, military industry, medical equipment, and the like.

In particular, as the unit price of a motor using a permanent magnet rises according to a sharp increase in the price of rare earth materials, a switched reluctance motor is receiving attention again as an alternative to a permanent magnet motor.

A switched reluctance motor (hereinafter referred to as 'SRM') is a double salient pole type and centralized winding type motor with windings located only in the stator.

In SRM, since torque is generated by reluctance by magnetic flux generated in the stator winding, SRM does not have permanent magnets and windings for generating magnetic flux in the rotor, unlike other motors.

Therefore, SRM has advantageous features such as being mechanically strong, stable for high-speed operation, inexpensive, and capable of operating under high heat or violent temperature changes.

In other words, SRM has a double salient pole structure, with an excitation winding only in the stator, and a simple structure without an excitation winding or magnet in the rotor. am.

In particular, SRM is a device or electric motor technology that converts electrical energy into rotating mechanical energy, with salient poles formed on the stator and rotor, respectively, and coils wound around the salient poles of the stator, while there is no coil or magnet in the rotor. Although it has a long history in the field, it has only recently been used in engineering applications for reasons such as difficult to control.

The driving principle of the SRM is to rotate the rotor using the reluctance torque generated according to the change in magnetoresistance.

Specifically, when the salient pole of the wound stator is excited, the rotational force is obtained by using the torque of the force to move the salient pole of the unwound rotor from the state in which it does not coincide with the salient pole of the stator.

That is, the force of the magnetic circuit is used to move the salient poles (protruding poles) from the highest reluctance state to the lowest reluctance.

Therefore, the SRM is configured such that the protruding poles of the stator and the rotor continuously exert a reluctance torque action. In general, in the case of a two-phase motor in which the inner ring rotates, it is composed of a four-pole stator and a two-pole rotor, and a three-phase A motor consists of a 6-pole stator and a 4-pole rotor, a 4-phase motor consists of an 8-pole stator and a 6-pole rotor, and a 5-phase motor consists of a 10-pole stator and an 8-pole rotor. .

These SRMs have a simpler structure than conventional induction motors or synchronous motors, so they can be produced at low cost.

In addition, since no windings or permanent magnets are used in the rotor, it has excellent durability and is not affected by the limited magnetic energy of the permanent magnet, so the torque per unit volume and efficiency are good, so the speed-output control characteristics are excellent. And there are many advantages, such as providing very high durability even in high-temperature environments.

However, as shown in FIG. 1, the SRM is relatively noisy than the conventional universal motor, which is a problem in that as the torque increases, the radial force increases, causing vibration and noise. Because.

Korean Patent Registration No. 10-1020994, title of invention 'Bearingless Switched Reluctance Motor with Hybrid Pole Structure' (Registration Date 2011.03.02.)

The present invention was created to solve the above problems, and it is an object of the present invention to provide an improved radial force reduction SRM in which vibration and noise can be reduced by improving the shape of the rotating magnetic pole to reduce the radial force. have.

In order to achieve the above object, an improved radial force reduction SRM according to an embodiment of the present invention includes a stator surrounded by a winding having a plurality of stator poles, and a plurality of rotating poles accommodated inside the stator and facing the outside. and a rotor having a The first and second holes are equally divided to reduce the radial force.

In addition, the first and second hole portions are arranged to be spaced apart from each other by a predetermined distance in the longitudinal direction, and are spaced apart from each other by the predetermined distance at both ends in the longitudinal direction.

In addition, the diameter of the hole portion is less than 1/2 of the rotor width.

In addition, the stator has six stator poles, and the rotor has four rotating poles.

Alternatively, the stator has 12 stator poles, and the rotor has 8 rotation poles.

According to the present invention, there is an advantage that a hollow hole (hole) is formed in the longitudinal direction inside the rotating magnetic pole to reduce the radial force (radial force).

In addition, since the hole portion corresponds to 40 to 60% of the length L in the longitudinal direction and is formed of first and second hole portions equally divided in the longitudinal direction, the radial force is reduced, so vibration and noise This has the advantage of being reduced.

In addition, since the first and second hole portions are arranged so that the hole portions are spaced apart by a predetermined distance in the longitudinal direction, but are spaced apart by the predetermined distance at both ends in the longitudinal direction, there is an advantage of further reducing the radial force.

In addition, it has the advantage of reducing vibration and noise by reducing the radial force by applying it to 6/4 SRM or 12/8 SRM.

1 is data comparing the noise of a conventional SRM and a general-purpose motor.
2 is shape data for comparing the conventional 6/4 SRM and the SRM proposed by the present invention.
3 is an exemplary perspective view of forming a cavity hole in an SRM.
FIG. 4 is a graph showing the average torque of FIG. 3 .
5 is a graph illustrating an average radial force of FIG. 3 .
FIG. 6 is a graph illustrating the peak radial force of FIG. 3 .
7 is an exemplary view for explaining the position of a hole (hole) in the rotating magnetic pole.
8 is various shapes for implementing the radial force reduction SRM.
9 is an enlarged exemplary view of the rotational pole in the SRM.
FIG. 10 is a diagram for the case where there is no hole in the SRM and the case where the hole has a size of 50%.
11 is a graph illustrating torque according to the case of FIG. 10 .
12 is a graph illustrating a radial force according to the case of FIG. 10 .
13 is an exemplary diagram illustrating a case in which there are two and three holes in an SRM.
14 is a graph illustrating a radial force according to the case of FIG. 13 .
15 is an exemplary diagram illustrating a case in which there is no hole in the SRM, a case in which there is one hole, a case in which there are two holes, and a case in which there are three holes.
16 is a graph illustrating torque according to the case of FIG. 15 .
17 is a graph illustrating a radial force according to the case of FIG. 15 .
18 is a diagram illustrating an improved radial force reduction SRM according to an embodiment of the present invention.
19 is an exemplary hole layout diagram when there are two holes in the SRM.
20 is a graph illustrating torque according to the case of FIG. 19 .
21 is a graph illustrating a radial force according to the case of FIG. 19 .
22 is a diagram illustrating an improved radial force reduction 6/4 SRM according to an embodiment of the present invention.
23 is data comparing the conventional SRM and the 6/4 SRM proposed by the present invention.
24 is a diagram illustrating an improved radial force reduction 12/8 SRM according to an embodiment of the present invention.
25 is data comparing the conventional SRM and the 12/8 SRM proposed by the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

The terminology used herein is for the purpose of referring to specific embodiments only, and is not intended to limit the present invention. As used herein, the singular forms also include the plural forms unless the phrases clearly indicate the opposite. The meaning of "comprising," as used herein, specifies a particular characteristic, region, integer, step, operation, element and/or component, and other specific characteristic, region, integer, step, operation, element, component, and/or group. It does not exclude the existence or addition of

Although not defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. Commonly used terms defined in the dictionary are additionally interpreted as having a meaning consistent with the related technical literature and the presently disclosed content, and unless defined, they are not interpreted in an ideal or very formal meaning.

The embodiments of the present invention described with reference to the drawings specifically represent ideal embodiments of the present invention. As a result, various modifications of the illustrations are expected, for example, modifications of manufacturing methods and/or specifications. Accordingly, the embodiment is not limited to a specific shape of the illustrated area, and includes, for example, a shape modification by manufacturing. Regions shown or described as being flat may have a characteristic that is generally spanning and/or non-linear.

Also, portions shown as having sharp angles may be rounded. Accordingly, the regions shown in the drawings are only approximate in nature, and their shapes are not intended to depict the exact shape of the regions, nor are they intended to narrow the scope of the present invention.

It is noted that the drawings are schematic and not drawn to scale. Relative dimensions and proportions of parts in the drawings are shown exaggerated or reduced in size for clarity and convenience in the drawings, and any dimensions are illustrative only and not limiting. And the same reference numerals are used to indicate corresponding or similar features in different embodiments to the same structures, elements, or parts appearing in two or more drawings.

The present invention has excellent durability because it does not use windings or permanent magnets in the rotor, and is not affected by the limited magnetic energy of the permanent magnets, so the torque and efficiency per unit volume are good, so the speed-output control characteristics are excellent, and the conventional induction motor or Although it is an SRM with many advantages such as being able to produce inexpensively and having a simpler structure than a synchronous motor, and providing very high durability even in a high-temperature environment, it is relatively noisy compared to the conventional universal motor, and therefore, as the torque increases, the It was created to solve the problem that vibration and noise are caused by increased radial force, and "improvement" in which vibration and noise are reduced because the radial force is reduced by improving the shape of the rotating magnetic pole It relates to the reduced radial force SRM".

2 is shape data for comparing the conventional 6/4 SRM and the SRM proposed by the present invention, FIG. 3 is an exemplary perspective view of forming a hollow hole in the SRM, and FIG. It is a graph showing the average torque, FIG. 5 is a graph showing the average radial force of FIG. 3 , and FIG. 6 is a graph showing the peak radial force of FIG. 3 .

In addition, FIG. 7 is an exemplary view for explaining the position of a hole in the rotating magnetic pole, FIG. 8 is various shapes for implementing the radial force reduction SRM, and FIG. 9 is an enlarged exemplary view of the rotating magnetic pole in the SRM. .

In addition, FIG. 10 is a diagram for the case where there is no hole in the SRM and the case where the hole is 50% in size, FIG. 11 is a graph showing the torque according to the case of FIG. 10, and FIG. 12 is It is a graph showing the radial force according to the case of Fig. 10, Fig. 13 is an exemplary view showing the case of two and three holes in the SRM, and Fig. 14 is the radial force according to the case of Fig. 13 is a graph showing

In addition, FIG. 15 is an exemplary view illustrating a case in which there is no hole in the SRM, a case in which there is one hole, a case in which there are two holes, and a case in which there are three, and FIG. It is a graph showing torque depending on the case, FIG. 17 is a graph showing the radial force according to the case of FIG. 15 , and FIG. 18 is a diagram showing an improved radial force reduction SRM according to an embodiment of the present invention.

19 is an exemplary hole arrangement when there are two holes in the SRM, FIG. 20 is a graph showing torque according to the case of FIG. 19, and FIG. 21 is a radial according to the case of FIG. It is a graph showing the force.

In addition, FIG. 22 is a diagram illustrating an improved radial force reduction 6/4 SRM according to an embodiment of the present invention, and FIG. 23 is data comparing the conventional SRM and the 6/4 SRM proposed by the present invention, FIG. 24 is a diagram illustrating an improved radial force reduction 12/8 SRM according to an embodiment of the present invention, and FIG. 25 is data comparing the conventional SRM and the 12/8 SRM proposed by the present invention.

Referring to the drawings, the improved radial force reduction SRM 100 according to an embodiment of the present invention includes a stator 110 surrounded by a winding 112 having a plurality of stator poles 111 , and the stator 110 . ) is accommodated on the inside and comprises a rotor 120 having a plurality of rotational magnetic poles facing outward, and the rotational magnetic pole 121 has a hollow hole portion 121h therein in the longitudinal direction. The first and second hole portions 121h-1 and 121h-2 are formed, wherein the hole portion 121h corresponds to 40 to 60% of the length L in the longitudinal direction and is equally divided in the longitudinal direction. formed to reduce the radial force.

Also, in the hole portion 121h, the first and second hole portions 121h-1 and 121h-2 are arranged to be spaced apart from each other by a predetermined distance in the longitudinal direction, and are spaced apart from each other by the predetermined distance at both ends in the longitudinal direction.

In addition, the diameter of the hole portion 121h is less than 1/2 of the rotor width W.

In addition, the stator 110 includes six stator poles 111 , and the rotor 120 includes four rotation poles 121 .

Alternatively, the stator 110 includes 12 stator poles 111 , and the rotor 120 includes 8 rotation poles 121 .

Then, the configuration and operation of the improved radial force reduction SRM 100 according to an embodiment of the present invention will be described in detail as follows.

First, as shown in FIG. 2, the SRM 100 proposed in the present invention was maintained the same except for the outer stator diameter when comparing the size and specifications with the conventional 6/4 SRM.

That is, the improved radial force reduction SRM 100 has a stack length of 30, an air-gap length of 0.25, a stator shaft diameter of 10, a voltage (V) of 310, and an output ( Output power) 1,200, rated speed 18,000, rated torque 0.60, etc. are the same.

As shown in FIG. 3, the improved radial force reduction SRM 100 proposed by the present invention forms a hollow hole part 121h in the rotating magnetic pole 121 to reduce the radial force. An experiment was conducted to reduce

That is, the improved radial force reduction SRM 100 proposed by the present invention was tested by varying the size (radius) and location of the cavity in the rotating magnetic pole 121 .

Here, the hole 121h is a cavity in which an empty space is formed.

As a result, as shown in FIGS. 4 to 6, average torque, average radial force, and peak radial force (force peak) according to the size (radius) and location of the hole portion And it was found.

For reference, the radial force refers to a force acting in a radial direction, and refers to a force generated in a radial direction or radially with respect to a center point of an axis when a motor rotates.

In particular, the radial force causes the vibration and acoustic noise to increase as the force is greater in the radial direction when the motor rotates.

Therefore, in the prior art, in order to reduce the radial force, the torque is also reduced, so in order to maintain the torque to some extent, the generation of the radial force has to be risked, but in the present invention, this problem is solved. Solved.

The improved radial force reduction SRM 100 proposed by the present invention is, as shown in FIGS. 7 and 8, the distance from the center of the rotor to the center of the hole and the diameter of the hole (dia). ) was adjusted to obtain the optimum value by applying holes in various sizes at various locations.

In particular, as shown in FIG. 9, the improved radial force reduction SRM 100 according to an embodiment of the present invention includes a stator 110 surrounded by a winding 112 having a plurality of stator poles 111 and, It is accommodated inside the stator 110 and comprises a rotor 120 having a plurality of rotational magnetic poles 121 facing outward, wherein the rotational magnetic pole 121 has a hollow hole therein. (121h) is formed in the longitudinal direction.

Figure 10 (a) is a case where there is no hole (hole) in the SRM, Figure 10 (b) is a case in which two hole (121h) in the SRM in a size of 50%, the present invention is proposed The following results are obtained in the radial force reduction SRM (100).

That is, the torque is similar to the case in which there is no hole part 121h as shown in blue in FIG. 11 or the case in which there is 50% of the hole part 121h as shown in brown color (50% hole), so that the average torque ) is 0.644 [Nm] for no holes and 0.637 [Nm] for 50% holes.

However, there is a difference in the average radial force or the peak radial force.

As shown in FIG. 12 , the radial force is 50% of the case where there is no hole 121h as shown in blue in FIG. 12 and 50% of the hole 121h as in the brown color of FIG. 12 ( 50% hole), and the average radial force is 6.33 [N] for no holes and 3.66 [N] for 50% holes.

In addition, the peak force is different from a case in which there is no hole 121h as shown in blue in FIG. 12 and a case in which there is 50% of a hole 121h as shown in brown in FIG. 12 (50% hole). is 26.71 [N] for no holes and 17.62 [N] for 50% holes.

It can be seen that since the improved radial force reduction SRM 100 proposed by the present invention has a hollow hole portion 121h therein, the radial force is greatly reduced.

Here, the 50% hole means that the longitudinal length of the hole part 121h corresponds to 50% of the stack length L, and the radial force reduction SRM 100 proposed in the present invention is the longitudinal length of the hole part 121h. is preferably formed between 40% and 60% of the stack length (L).

That is, the improved radial force reduction SRM 100 proposed in the present invention is between 40% and 60% of the stack length L or the length L of the rotary magnetic pole 121 in the longitudinal direction of the hole portion 121h. Since the directional length is formed, an effect of reducing a radial force can be obtained.

For reference, in the present invention, the stack length (L) has the same meaning as the length (L) in the longitudinal direction of the rotating magnetic pole 121 .

Next, as shown in FIG. 13 , the improved radial force reduction SRM 100 proposed by the present invention was performed by comparing two and three holes in the SRM.

As a result, the radial force, as shown in FIG. 14, when there are two holes in the SRM (blue), the fluctuation width is small and relatively constant, but when there are three holes in the SRM ( Brown), the ups and downs were large and the ups and downs were relatively large.

That is, when the radial force has two holes in the SRM (blue), the fluctuation width is small and relatively constant, but when there are three holes in the SRM (brown color), the fluctuation width is large and relatively ups and downs ( ups and downs) is large, and the average force is 1.13 [N] with 2 holes (blue) and 2.54 [N] with 3 holes (brown).

In addition, the peak force is 5.46 [N] when there are two holes (blue) and 20.95 [N] when there are three holes (brown).

Therefore, the improved radial force reduction SRM 100 proposed by the present invention derives an optimal result when there are two holes in the SRM, as shown in FIGS. 15 to 18 .

As shown in Fig. 15, when there is no hole in the SRM, when there is one hole, when there are two holes, and when there are three, the following results were obtained. .

That is, in the improved radial force reduction SRM 100 according to an embodiment of the present invention, as shown in FIG. 16 , when there is no hole in the SRM, when there is only one hole, the hole (hole) ) is 2 and 3, the torque is similar, but as shown in FIG. 17, when there is no hole in the SRM, when there is one hole, the hole is In the case of 2 and 3, the smallest radial force appears when there are 2 holes.

In conclusion, an improved radial force reduction SRM 100 according to an embodiment of the present invention is proposed as shown in FIG. 18 .

1) The length or stack length of the rotating magnetic pole 121 in the longitudinal direction is L.

2) The hole portion 121h is a cylindrical cavity, in which a first hole portion 121h-1 and a second hole portion 121h-2 are formed, and the length of the first hole portion 121h-1 is Lh1, The length of the second hole 121h-2 is Lh2. However, in the present invention, the hole portion 121h may be implemented in a cylindrical shape or various shapes as needed.

이다.3) If the total length of the hole portion 121h is α, the length Lh1 of the first hole portion 121h-1 = the length Lh2 of the second hole portion 121h-2 =

am.

4) The hole portion 121h corresponds to 40 to 60% of the length L in the longitudinal direction.

5) If the total length of the interval between the hole portions 121h is β, β = (L - α).

이다.6) The predetermined intervals between the hole portions 121h are Ld1, Ld2, and Ld3, respectively, and Ld1 ≒ Ld2 ≒ Ld3 ≒

am.

보다 크지 않다.7) The diameter of the hole portion 121h is the same as the width W of the rotating magnetic pole 121.

not bigger than

이하이다.That is, the diameter of the hole portion 121h is

is below.

In addition, as shown in FIG. 19 , the improved radial force reduction SRM 100 according to an embodiment of the present invention derives an optimal result when spaced apart at regular intervals inside of the two holes. .

As shown in FIG. 19, when there are two holes, (a) in which holes are arranged at regular intervals in the longitudinal direction inside the rotating magnetic pole, and longitudinally inside the rotating magnetic pole, but at both ends ( The following results were obtained by performing (b) in which the hole is arranged and (c) in which the hole is arranged in the longitudinal direction but clustered in the center inside the rotating magnetic pole.

That is, the improved radial force reduction SRM 100 according to an embodiment of the present invention is similar in torque in the case of (a), (b), and (c) of FIG. 18 as shown in FIG. 20 . However, as shown in FIG. 21, when there are two holes, (a) in which the holes are arranged at regular intervals in the longitudinal direction inside the rotating magnetic pole, the remaining (b) and (c) cases A smaller undulation, a relatively small and stable radial force appears.

In particular, when the improved radial force reduction 6/4 SRM 100 according to an embodiment of the present invention is formed by stacking the rotor 121 with a 0.35 mm thick thin plate, as shown in FIG. The longitudinal length (L) corresponds to 57 thin plate layers, each of Lh1 and Lh2 corresponds to the thickness of 13 thin plate layers, Ld1 is 10 thin plate layers, Ld2 is 11 thin plate layers, and Ld3 is 10 thin plate layers. applicable.

Here, the gap Ld2 between the first hole part 121h-1 and the second hole part 121h-2 differs by one thin plate layer (0.35mm) from each of Ld1 and Ld3, but this difference can be regarded as the same or similar. can

In addition, as shown in FIG. 22 , in the hole portion 121h , a first hole portion 121h-1 and a second hole portion 121h-2 are formed in a line in the longitudinal direction near the root of the rotor 121 .

23 is data comparing the conventional SRM and the 6/4 SRM proposed by the present invention. It can be seen from the graph that although they have very similar values in torque, there is a large difference in radial force. have.

As shown in FIG. 24, the improved radial force reduction 12/8 SRM 100 according to another embodiment of the present invention is formed by stacking the rotor 121 with a thickness of 0.35 mm thin plates in the longitudinal direction of the rotor. The length L corresponds to 57 thin plate layers, each of Lh1 and Lh2 corresponds to the thickness of 13 thin plate layers, Ld1 corresponds to 10 thin plate layers, Ld2 corresponds to 11 thin plate layers, and Ld3 corresponds to 10 thin plate layers. .

Here, the gap Ld2 between the first hole part 121h-1 and the second hole part 121h-2 differs by one thin plate layer (0.35mm) from each of Ld1 and Ld3, but this difference can be regarded as the same or similar. can

In addition, as shown in FIG. 24 , in the hole portion 121h , a first hole portion 121h-1 and a second hole portion 121h-2 are formed in a line in the longitudinal direction near the root of the rotor 121 .

Figure 25 is data comparing the conventional SRM and the 12/8 SRM proposed by the present invention. It can be seen from the graph that although they have very similar values in torque, there is a large difference in radial force. have.

In summary, the improved radial force reduction SRM 100 according to an embodiment of the present invention includes a stator 110 surrounded by a winding 112 having a plurality of stator poles 111 , and the stator 110 . It is accommodated on the inside of the rotor 120 having a plurality of rotating magnetic poles 121 facing outward.

In addition, the rotating magnetic pole 121 has a hollow hole portion 121h formed therein in the longitudinal direction, wherein the hole portion 121h corresponds to 40 to 60% of the length L in the longitudinal direction, and the longitudinal direction is formed of the first and second hole portions 121h-1 and 121h-2 divided into equal sizes to reduce the radial force.

In addition, the first and second hole portions 121h-1 and 121h-2 are arranged to be spaced apart (Ld1, Ld3) by a predetermined distance in the longitudinal direction of the hole portion 121h, and at both ends in the longitudinal direction, the predetermined interval Spaced apart by (Ld2), the diameter of the hole portion (121h) is less than 1/2 of the rotor width (W).

In addition, as shown in FIG. 22, the SRM 100 for reducing radial force according to an embodiment of the present invention includes a stator 110 having six stator poles 111 and four rotating poles 121. It may be a 6/4 SRM composed of a rotor 120 provided with, and a radial force reduction SRM 100 according to another embodiment of the present invention, as shown in FIG. 24 , includes 12 stator poles 111 It can also be applied to the 12/8 SRM consisting of a stator 110 having a stator 110 and a rotor 120 having eight rotating magnetic poles 121 .

Accordingly, the improved radial force reduction SRM 100 according to an embodiment of the present invention can expect the following effects.

According to the present invention, a hollow hole portion 121h is formed in the longitudinal direction inside the rotating magnetic pole 121 to reduce the radial force.

In addition, the hole portion 121h corresponds to 40 to 60% of the length L in the longitudinal direction and is formed of first and second hole portions 121h-1 and 121h-2 equally divided in the longitudinal direction. Since the radial force is reduced, there is an advantage in that vibration and noise are reduced.

In addition, the first and second hole portions 121h-1 and 121h-2 are arranged such that the hole portions 121h are spaced apart from each other by a predetermined distance in the longitudinal direction. It has the advantage of further reducing the radial force.

In addition, it has the advantage of reducing vibration and noise by reducing the radial force by applying it to 6/4 SRM or 12/8 SRM.

The above description is merely illustrative of the technical idea of the present invention, and various modifications, changes and substitutions may be made by those skilled in the art without departing from the essential characteristics of the present invention. will be.

Accordingly, the embodiments disclosed in the present invention and the accompanying drawings are intended to explain, not to limit the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments and the accompanying drawings. .

The protection scope of the present invention should be construed by the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

100: SRM proposed by the present invention
110: stator
111: fixed stimulus
120: rotor
121: rotating magnetic pole
121h: hole part
121h-1: first hole
121h-2: second hole

Claims (5)

a stator surrounded by windings having a plurality of stator poles;
and a rotor accommodated inside the stator and provided with a plurality of rotating magnetic poles facing outward,
The rotating magnetic pole has a hollow hole (hole) formed therein in the longitudinal direction, the hole (hole) corresponds to 40 to 60% of the length in the longitudinal direction, the first and second holes equally divided in the longitudinal direction An improved radial force reduction SRM, characterized in that it is formed as a negative force to reduce the radial force. The method of claim 1,
The improved radial force reduction SRM, characterized in that the first and second hole portions are arranged to be spaced apart from each other by a predetermined distance in the longitudinal direction, and spaced apart from each other by the predetermined distance at both ends in the longitudinal direction. delete The method of claim 1,
The stator has six stator poles,
The improved radial force reduction SRM, characterized in that the rotor is provided with four rotating poles. The method of claim 1,
The stator has 12 stator poles,
The improved radial force reduction SRM, characterized in that the rotor is provided with eight rotating poles.

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