WO2017073821A1

WO2017073821A1 - Rotor and permanent magnet-type motor including same

Info

Publication number: WO2017073821A1
Application number: PCT/KR2015/011557
Authority: WO
Inventors: 유세현; 서정무; 이정종; 정인성; 허진; 정채림
Original assignee: 전자부품연구원; 울산대학교 산학협력단
Priority date: 2015-10-30
Filing date: 2015-10-30
Publication date: 2017-05-04
Also published as: KR20170051638A; KR101736051B1

Abstract

A rotor and a permanent magnet-type motor including the same are disclosed. The rotor comprises: a rotary shaft insertion hole for inserting a rotary shaft thereinto; a rotor iron core having a plurality of permanent magnet insertion holes, which are continuously formed therein, are maintained in a V shape by being spaced from the rotary shaft insertion hole, and have each of V-shaped frames forming a zigzag shape by including at least two curves; and a plurality of permanent magnets inserted into the plurality of permanent magnet insertion holes.

Description

Rotor and permanent magnet motor including same

The present invention relates to a permanent magnet electric motor, and more particularly, to a rotor for concentrating magnetic flux by changing only the shape of the permanent magnet in a state of maintaining the amount of the permanent magnet as it is, and a permanent magnet electric motor including the same.

Hybrid cars and electric cars are attracting attention due to the detriment of fossil fuels and the environmental impact caused by air pollution. Hybrid cars use an internal combustion engine as a main power source and an electric motor as an auxiliary power source. Electric vehicles are motor vehicles using only electric motors.

Electric vehicles are expected to replace transitional vehicles such as hybrid vehicles due to the characteristics of pollution-free and carbon dioxide-free vehicles while driving.

On the other hand, the electric motor of the electric vehicle acts like an engine and receives electrical energy from a battery and converts it into mechanical energy. Accordingly, the output and the driving distance of the electric vehicle are greatly affected by the performance of the battery and the electric motor.

Therefore, in order to improve the output and the driving distance of the electric vehicle, it is important to improve the battery performance and the power density and efficiency of the electric motor.

In addition, with the recent global environmental problems and the arrival of the carbon economy, the high efficiency of the system is emerging as a very important issue not only in electric vehicles but also in all fields such as home appliances. Accordingly, there is a further demand for higher efficiency of the motor as a key driving source of the system.

On the other hand, the permanent magnet electric motor is composed of a stator in which a winding wound around a stator iron core made of a magnetic material, and a rotor rotatably disposed in the stator iron core of the stator and having a permanent magnet therein.

In particular, the permanent magnet motor has a high residual magnetic flux density in order to increase the output density by concentrating the magnetic flux through a flux type using a permanent magnet in order to secure the low output density, or to obtain a higher output. Eggplants can compensate for insufficient magnetic flux density by using expensive permanent magnets, increasing the amount of permanent magnets, or by inserting more auxiliary permanent magnets.

However, in such a case, since a side effect occurs that causes an increase in the manufacturing cost of the permanent magnet type motor, it is necessary to develop a new power density improvement that can improve the problem.

The technical problem to be achieved by the present invention is to provide a rotor and a permanent magnet electric motor including the same to change the shape of the permanent magnet to maintain the amount of the permanent magnet as it is to concentrate the magnetic flux.

In order to achieve the above object, the rotor according to the present invention, the rotary shaft insertion hole for inserting the rotary shaft, and each frame of the V-shaped at least two or more bends while maintaining the V-shaped spaced apart from the rotary shaft insertion hole And a plurality of permanent magnets inserted into the plurality of permanent magnet insertion holes and a rotor iron core in which a plurality of zigzag permanent magnet insertion holes are continuously formed.

In addition, the rotor iron core, characterized in that the outer periphery is formed in an arc shape.

In addition, the V-shape, it characterized in that it comprises an included angle of 5 ° to 85 °.

In addition, each of the V-shaped frame is characterized in that at least three or more permanent magnet insertion holes are formed, and the formed permanent magnet insertion holes form a zigzag shape with a preset included angle and bend.

In addition, the at least three or more permanent magnet insertion holes are characterized in that the length of each of the longitudinal direction is the same or shorter as the permanent magnet insertion hole closer to the rotation shaft insertion hole.

In addition, the at least three or more permanent magnet insertion holes are characterized in that the predetermined angle is the same, or the smaller the angle of the bend close to the rotation axis insertion hole is formed.

The permanent magnet electric motor including the rotor according to the present invention includes a rotation shaft insertion hole for inserting a rotation shaft, and each frame of the V-shape is curved at least two or more while being spaced apart from the rotation shaft insertion hole to maintain a V shape. Rotor and pipe shape including a plurality of permanent magnet insertion holes are formed continuously in a zigzag shape, including a plurality of permanent magnets inserted into the plurality of permanent magnet insertion holes, including The stator includes a stator provided inside the pipe shape.

In addition, the magnetic flux is generated in the clockwise or counterclockwise direction around the outer periphery connecting the respective V-shaped frame.

According to the rotor and the permanent magnet motor including the same according to the present invention, by changing only the shape of the permanent magnet in a state of maintaining the amount of the permanent magnet as it is, the magnetic flux is concentrated to increase the output density of the motor, and desired output density Can be reached.

In addition, since the amount of permanent magnets are kept intact, no additional manufacturing costs are required, thereby reducing costs.

1 is a view for explaining a rotor according to an embodiment of the present invention.

2 is a view for explaining a magnetic flux path of the permanent magnet motor according to an embodiment of the present invention.

3 is a view for explaining the basic rotor and the arc-shaped rotor according to an embodiment of the present invention.

4 is a view for explaining a performance comparison of the cogging torque of the basic rotor and the arc-shaped rotor according to an embodiment of the present invention.

5 is a view for explaining the performance comparison of the counter-electromotive voltage of the basic type rotor and the arc type rotor according to an embodiment of the present invention.

6 is a view illustrating a conventional permanent magnet shape and a permanent magnet shape according to an embodiment of the present invention.

FIG. 7 is a view for explaining a performance comparison with respect to the pore magnetic flux density of the permanent magnet shapes shown in FIG. 6.

FIG. 8 is a diagram for explaining a performance comparison of counter electromotive voltages of the permanent magnet shapes illustrated in FIG. 6.

FIG. 9 is a diagram for explaining a performance comparison of output torques of the permanent magnet shapes illustrated in FIG. 6.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it is noted that the same reference numerals are assigned to the same components as much as possible, even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function is apparent to those skilled in the art or may obscure the gist of the present invention, the detailed description thereof will be omitted.

Referring to Figure 1, the rotor 100 changes the shape of the permanent magnet in the state of maintaining the amount of the permanent magnet as it is to concentrate the magnetic flux to increase the output density of the motor, to reach the desired output density. The rotor 100 includes a rotor iron core 10 and a plurality of permanent magnets 20.

The rotor core 10 is a core of the rotor, and includes a rotation shaft insertion hole 30 for inserting the rotation shaft and a plurality of permanent magnet insertion holes 11.

The rotary shaft insertion hole 30 is a hole formed in the center of the rotor iron core 10 to insert a rotary shaft (not shown). Therefore, the rotor iron core 10 may be connected to the rotating shaft to be inserted to rotate.

The plurality of permanent magnet insertion holes 11 are holes into which the plurality of permanent magnets 20 are inserted. The plurality of permanent magnet insertion holes 11 are continuously spaced apart from the rotation shaft insertion hole 30 at regular intervals while maintaining a V shape.

The V-shape maintains a predetermined first included angle θ, and the first frame 12 and the second frame 16 having a branch shape are formed. Here, the first frame 12 and the second frame 16 form a V shape when the virtual center lines are connected to each other, and each of the plurality of permanent

magnet insertion holes

13, 14, 15, 17, 18, and 19 is formed. Include.

The V-shape has a maximum pore magnetic flux density and is formed to be spaced apart from the point where the first frame 12 and the second frame 16 do not collide with each other. Preferably, the first included angle θ may be between 5 ° and 85 °. Here, the first included angle θ is an angle generated when the virtual center line with respect to the first frame 12 and the second frame 16 intersects.

The first frame 12 and the second frame 16 each include at least two or more bends, which are zigzag. In this case, at least three permanent magnet insertion holes are formed in the first frame 12 and the second frame 16 to form at least two bends, and the formed permanent magnet insertion holes have a predetermined second included angle ( It is formed in a zigzag shape by α) and the third included angle β.

The first frame 12 includes a first permanent magnet insertion hole 13, a second permanent magnet insertion hole 14, and a third permanent magnet insertion hole 15, and the second frame 16 has a fourth permanent magnet. The magnet insertion hole 17, the fifth permanent magnet insertion hole 18, and the sixth permanent magnet insertion hole 19 are included.

Here, the first and fourth permanent

magnet insertion holes

13 and 17 have a length in the longitudinal direction of the first length a, and the second and fifth permanent

magnet insertion holes

14 and 18 have a length in the longitudinal direction. It is the 2nd length b, and the 3rd and 6th permanent

magnet insertion holes

15 and 19 are the 3rd length c of the length in the longitudinal direction. In addition, the included angles of the first and second permanent

magnet insertion holes

13 and 14 and the included angles of the fourth and fifth permanent

magnet insertion holes

17 and 18 are the second included angle α, and the second and third permanent magnets are included. The included angles of the

insertion holes

14 and 15 and the included angles of the fifth and sixth permanent

magnet insertion holes

18 and 19 are the third included angle β.

At this time, the optimized values of the first to third lengths (a, b, c) and the second and third included angles (α, β) may be calculated through simulation.

The first step arbitrarily adjusts the first to third lengths (a, b, c) and the second and third included angles (α, β). The second step calculates the adjusted first to third lengths a, b, and c and the back electromotive force BEMF of the second and third included angles α and β. The third step is set to an optimized value when the counter electromotive voltage of the permanent magnet motor according to the present invention is greater than or equal to 80% of the base electromotive voltage of the reference motor, and performs the first stage again if not. Here, the reference motor may be an electric motor including a neodymium magnet (Nd-PM).

On the other hand, if the first to third lengths (a, b, c) are optimized, the first to third lengths (a, b, c) have the same length in their respective longitudinal directions, or permanent magnet insertion close to the rotation shaft insertion hole. The holes may be formed shorter (a ≥ b ≥ c).

That is, the longitudinal lengths a, b, and c of the first to third permanent magnet insertion holes 13, 14, and 15 are the same, or the longitudinal length a of the first permanent magnet insertion holes 13 is the same. It may be longer than the longitudinal length (b) of the second permanent magnet insertion hole 14, the longitudinal length (b) of the second permanent magnet insertion hole 14 is the length of the third permanent magnet insertion hole (15). It may be longer than the direction length (c). In addition, the longitudinal lengths a, b, and c of the fourth to sixth permanent magnet insertion holes 17, 18, and 19 are the same, or the longitudinal length a of the fourth permanent magnet insertion hole 17 is defined as 5 may be longer than the longitudinal length (b) of the permanent magnet insertion hole (18), and the longitudinal length (b) of the fifth permanent magnet insertion hole (18) is the longitudinal direction of the sixth permanent magnet insertion hole (19). It may be longer than length c.

At this time, even if the first and

second frames

12 and 16 each include n permanent magnet insertion holes instead of three permanent magnet insertion holes, the lengths thereof in the longitudinal direction are the same or close to the rotation shaft insertion holes. The permanent magnet insertion hole is the same as the feature that can be formed short.

In addition, if the second and third included angles α and β are optimized, the second and third included angles α and β may be smaller as the respective included angles are the same or as the included angles of the bends closer to the rotation shaft insertion holes. (α ≧ β).

That is, the second included angle α between the first and second permanent magnet insertion holes 13 and 14 is equal to the third included angle β between the second and third permanent magnet insertion holes 14 and 15, or It can be formed large. Also, the second included angle α between the fourth and fifth permanent magnet insertion holes 17 and 18 is equal to or larger than the third included angle β between the fifth and sixth permanent magnet insertion holes 18 and 19. Can be formed.

Preferably, the second included angle α may be greater than 160 ° and less than 175 ° (160 ° <α <175 °) and the third included angle β may be greater than 155 ° and less than 175 °. (155 ° <β <175 °).

In this case, even when the first and

second frames

12 and 16 are curved in two or more bends, the included angles of the bends may be the same as each other, or the smaller the angles of the bends close to the rotation shaft insertion holes 30. The same features apply.

The plurality of permanent magnets 20 are inserted into the plurality of permanent magnet insertion holes 11. The plurality of permanent magnets 20 may be ferritic permanent magnets. The plurality of permanent magnets 20 are inserted into the corresponding plurality of permanent magnet insertion holes 11.

That is, the first permanent magnet 23 is inserted into the first permanent magnet insertion hole 13, the second permanent magnet 24 is inserted into the second permanent magnet insertion hole 14, the third permanent magnet 25 ) Is inserted into the third permanent magnet insertion hole 15, the fourth permanent magnet 27 is inserted into the fourth permanent magnet insertion hole 17, the fifth permanent magnet 28 is the fifth permanent magnet insertion hole The sixth permanent magnet 29 is inserted into the sixth permanent magnet insertion hole 19.

Therefore, by inserting the plurality of permanent magnets 20 into the plurality of permanent magnet insertion holes 11 formed in the rotor iron core 10, the plurality of permanent magnets 20 have a V-shape while maintaining the V-shape. The

frames

12 and 16 may be arranged in a curved shape having a zigzag shape.

Referring to FIG. 2, the permanent magnet electric motor includes a rotor 100 and a stator 200.

The stator 200 includes a stator iron core (not shown) formed in a pipe shape and a winding (not shown) wound around the stator iron core, and includes a rotor 100 inside the pipe shape. At this time, the stator 200 is provided to be spaced apart from the rotor 100 at regular intervals, the rotation axis is connected to the center of the rotor 100 to rotate the rotor 100. Through this, a magnetic flux is formed between the rotor 100 and the stator 200.

In detail, the stator 200 is wound around a stator yoke (not shown) formed in the stator core. At this time, when the rotor 100 rotates by the rotating shaft, a magnetic flux is formed between the permanent magnet 20 included in the rotor 100 and the winding wound on the stator 200 to generate current in the winding. do.

Particularly, in order to concentrate the magnetic flux, the permanent magnet electric motor is arranged such that at least two or more bends are formed in a zigzag shape while maintaining the V shape of the rotor 100 with respect to the permanent magnet 20. do. The permanent magnet 20 is spaced apart at regular intervals from the rotation shaft insertion hole 30 of the rotor 100 to form a V-shape continuously. The permanent magnet 20 thus formed generates current for the q-axis and the d-axis.

For example, the permanent magnet 20a and the permanent magnet 20b are each formed in two or more bends in a zigzag shape while maintaining a V shape, and a current about the d axis is generated in the center of the V shape, respectively. The current on the q-axis is generated between the permanent magnet 20a and the permanent magnet 20b.

Through this, the permanent magnet motor generates a magnetic flux in a clockwise or counterclockwise direction with respect to the outer periphery connecting the respective V-shaped frames. At this time, the direction of the magnetic flux may be changed according to the magnetic direction of the plurality of permanent magnets (20).

3 is a view for explaining the basic rotor and the arc-shaped rotor according to an embodiment of the present invention. Fig. 3 (a) shows the basic rotor and Fig. 3 (b) shows the arc rotor.

Referring to FIG. 3, the rotor 100 is divided into a basic rotor 100a and an arc rotor 100b.

The basic rotor 100a is a rotor including a basic rotor iron core 10a, and the arc rotor 100b is a rotor including an arc rotor iron core 10b. While the basic rotor iron core 10a has a general arc shape with an outer circumference, the arc rotor iron core 10b has an arc shape with an outer circumference protruding more than a general arc shape.

In the arc-shaped rotor core 10b, an air gap, which is a space spaced from the stator 200, is closer to the arc-shaped center and a general arc shape. Through this, the arc type rotor 100b may improve cogging torque than the basic type rotor 100a.

4 is a view for explaining the performance evaluation of the cogging torque of the basic rotor and the arc-shaped rotor according to an embodiment of the present invention, Figure 5 is a basic rotor and arc type according to an embodiment of the present invention It is a figure for demonstrating the performance evaluation about the counter electromotive voltage of a rotor.

4 and 5, the performance evaluation on the cogging torque and counter-electromotive voltage of the basic rotor and the arc rotor. The basic configuration of the basic rotor and the arc rotor is the same, and only the rotor iron core is used for the basic rotor iron and the arc rotor iron core, respectively.

The arc-type rotors had less peak-to-peak values over time than the basic rotors, while also reducing ripple. Thus, the arc rotor has a cogging torque of about 46% improvement over the basic rotor.

On the contrary, it was confirmed that the counter electromotive voltage values of the basic rotor and the arc rotor were almost similar.

Therefore, it was confirmed that changing the rotor core of the rotor from the basic type to the arc type has an effect of improving cogging torque and ripple.

6 is a view illustrating a conventional permanent magnet shape and a permanent magnet shape according to an embodiment of the present invention. Figure 6 (a) is a view for explaining the spoke type (spoke type) permanent magnet shape, Figure 6 (b) is a view for explaining the V-shaped permanent magnet shape, Figure 6 (c) according to the present invention It is a figure which shows a permanent magnet shape.

Referring to Figure 6, the conventional spoke-type permanent magnet shape is a permanent magnet is arranged in a single straight shape, the V-shaped permanent magnet shape maintains a constant included angle in the state in which the spoke-type permanent magnet is bisected in the width direction The permanent magnets are spaced apart from each other, and the permanent magnets according to the present invention have a zigzag shape in which each frame is arranged in a V-shaped rotor, and the permanent magnets are disposed.

Therefore, the shape of the permanent magnet shown in Figure 6 (a) to Figure 6 (c) is the same amount of the permanent magnet, but the shape of the permanent magnet is different.

FIG. 7 is a view for explaining a performance comparison of the pore flux densities of the permanent magnet shapes shown in FIG. 6, and FIG. 8 is a view for explaining a performance comparison with respect to the counter electromotive voltage of the permanent magnet shapes shown in FIG. 6. 9 is a view for explaining a performance comparison of the output torque of the permanent magnet shapes shown in FIG.

7 to 9, the pore magnetic flux density, counter electromotive voltage and output torque of the permanent magnet shapes shown in FIG. 6 were compared.

As shown in Figs. 7 (a) and 7 (b), the pore magnetic flux density has a maximum value of 0.5 (T) for spoke type permanent magnets and a maximum value of 0.75 (T) for V-shaped permanent magnets. ), The maximum value for the permanent magnet of the present invention was measured as 0.9 (T).

That is, it can be seen that the shape of the permanent magnet of the present invention has a higher pore magnetic flux density than those of the conventional permanent magnet.

As shown in Figs. 8 (a) and 8 (b), the counter electromotive voltage has a maximum value of 41.1982 (V _ms ) for the spoke permanent magnet and 43.2478 (V) for the V-shaped permanent magnet. _ms ), and the maximum value for the permanent magnet of the present invention was measured to be 50.7307 (V _ms ).

That is, it can be seen that the shape of the permanent magnet of the present invention is higher in counter voltage than those of the conventional permanent magnet.

As shown in Figs. 9 (a) and 9 (b), the output torque has a maximum value of 3.2 Nm for the spoke permanent magnet, and a maximum value of 3.8 Nm for the V-shaped permanent magnet. The maximum value for the permanent magnet of the present invention was measured to 4.5 (Nm).

That is, it can be seen that the shape of the permanent magnet of the present invention has a higher output torque than those of the conventional permanent magnet.

Therefore, the shape of the permanent magnet of the present invention can increase the output density of the electric motor by concentrating the magnetic flux more than the shape of the conventional permanent magnet in a state of maintaining the permanent magnet amount as it is. In other words, the output density can be increased without increasing the manufacturing cost.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific preferred embodiments described above, and the present invention belongs to the present invention without departing from the gist of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

[Description of the code]

10: rotor iron core 10a: basic rotor iron core

10b: arc-type rotor core 11: permanent magnet insertion hole

12: 1st frame 13: 1st permanent magnet insertion hole

14: 2nd permanent magnet insertion hole 15: 3rd permanent magnet insertion hole

16: 2nd frame 17: 4th permanent magnet insertion hole

18: 5th permanent magnet insertion hole 19: 6th permanent magnet insertion hole

20, 20a, 20b: permanent magnet 23: first permanent magnet

24: 2nd permanent magnet 25: 3rd permanent magnet

27: 4th permanent magnet 28: 5th permanent magnet

29: 6th permanent magnet 30: rotation shaft insertion hole

40: void 100: rotor

100a: basic rotor 100b: arc rotor

200: stator a: first length

b: second length c: third length

θ: first included angle α: second included angle

β: third included angle

Claims

A rotary shaft insertion hole for inserting the rotary shaft and a plurality of permanent magnet insertion holes in which each of the V-shaped frames comprise at least two bends and form a zig-zag shape while being spaced apart from the rotary shaft insertion hole maintain a V shape. Rotor iron core formed as; And

A plurality of permanent magnets inserted into the plurality of permanent magnet insertion holes;

Rotor comprising a.
The method of claim 1,

The rotor iron core is a rotor, characterized in that the outer periphery is formed in an arc shape.
The method of claim 1,

The V-shape is,

A rotor comprising an included angle between 5 ° and 85 °.
The method of claim 1,

Each frame of the V-shape,

At least three permanent magnet insertion holes are formed, the rotor is characterized in that the formed permanent magnet insertion hole is formed in a zigzag shape with a predetermined included angle bends.
The method of claim 4, wherein

The at least three permanent magnet insertion holes,

And the length of each longitudinal direction is the same, or the shorter the permanent magnet insertion hole is closer to the rotation shaft insertion hole.
The method of claim 4, wherein

The at least three permanent magnet insertion holes,

And the preset angle of inclination is the same or smaller as the angle of inclination close to the rotation shaft insertion hole is smaller.
A rotary shaft insertion hole for inserting the rotary shaft and a plurality of permanent magnet insertion holes in which each of the V-shaped frames comprise at least two bends and form a zig-zag shape while being spaced apart from the rotary shaft insertion hole maintain a V shape. A rotor comprising a rotor iron core formed of a plurality of permanent magnets inserted into the plurality of permanent magnet insertion holes; And

A stator formed in a pipe shape and having the rotor provided inside the pipe shape;

Permanent magnet electric motor including a rotor including a.
The method of claim 7, wherein

Permanent magnet-type motor, characterized in that the magnetic flux is generated clockwise or counterclockwise around the outer periphery connecting between the V-shaped frame.