TWI513146B - Rotor structure of interior-permanent-magnet motor - Google Patents

Description

Rotor structure of built-in permanent magnet motor

The present invention relates to electric motors, and more particularly to a rotor construction of a built-in permanent magnet motor.

A permanent magnet motor is a general term for a motor that replaces the mechanical rectification of a carbon brush and a commutator with a semiconductor switch. The type of the motor can be distinguished by the back electromotive waveform, and the permanent magnet is placed on the rotor. The surface or the different spatial patterns embedded in the rotor are divided into surface type, built-in type and in-line type. Among them, the surface type permanent magnet motor adheres the magnet to the surface of the rotor, and obtains a larger one. Magnetic flux density, but because it is not ideal for the positioning technology of the magnet, it is easy to disengage the rotor at high speed, and it is necessary to strengthen the technique of attaching the magnet to the surface of the rotor.

In contrast, the built-in type and the embedded type permanent magnet motor embed the magnet inside the rotor to form a space type in which the rotor core surrounds the magnet, and is suitable for high-speed operation, in which the permanent magnet is buried. The magnetic flux concentrated type built-in type permanent magnet motor in the rotor is a motor of the same type because the magnetic flux is added to the pole surface by the magnets on both sides, and has only a single-sided magnetic flux with respect to the general rotor. Even the magnetic flux density of the air gap can exceed the magnetic flux density of the magnet, and at the same time, the magnetic island area of the rotor increases, and the inductance difference of the dq axis is enlarged, so that the permanent magnet motor of the equal type has a higher reluctance torque. It is more suitable for wide-area operating speed range.

Wherein, the core material used for the rotor for burying the magnet is usually provided It has the characteristics of high magnetic permeability to reduce the magnetic resistance of the magnetic circuit, but in order to avoid the phenomenon of magnetic short circuit, in the prior art, as shown in the first figure, the rotor is made of a magnetically permeable material and a non-magnetically permeable material. The component is formed such that the partial region (1a) made of the non-magnetic material is located at both ends of the long axis of the rectangle of the magnet (1b) to avoid the occurrence of a magnetic short circuit.

Further, the conventional built-in permanent magnet motor shown in the second figure During the operation, in order to facilitate the manufacturing and processing of the rotor in the industry, the magnet (2a) is accommodated in the hollow groove (2c) of the rotor (2b), and the volume of the empty groove (2c) is larger than that of the accommodated magnet (2a) The volume is such that there is a gap (2d) between the hollow groove (2c) and the radially outer edge of the rotor (2b), and the distribution of the magnetic flux density is adjusted by the magnetoresistance of the equal gap (2d).

And the conventional technique of forming a magnetoresistive region by using space, except those shown in the second figure In addition, as disclosed in the third and fourth figures, one end of each magnet (3a) is adjacent to two shielding spaces (3b) (3c), or as shown in the fifth figure, to a larger one. The slot (4a) is located between one end of the adjacent magnet (4b).

It can be known from the conventional techniques shown in the first to fifth figures that no matter whether it is space or not In the case of changing the shape of the rotor, or forming a part of the rotor with a non-magnetic material, it is necessary to control the magnetic flux density by means of a technique to make the magnetic lines more concentrated, and to make a more efficient intersection with the stator winding. At the same time, through the restriction of the magnetic field travel area, to reduce the torque, even though many similar technologies have been exposed in the prior art, there are still some areas for improvement. It is difficult to say that The prior art has been perfected.

Therefore, the main object of the present invention is to provide a built-in permanent magnet motor. The rotor structure, which allows for a further increase in magnetic flux density and concentration of magnetic lines of force to enhance the thrust of the motor.

Therefore, in order to achieve the above object, the present invention provides a built-in permanent magnet motor The sub-constructor is a plurality of permanent magnets buried in the core member in a radiation manner, so as to be close to one end of the center of curvature of the core member, respectively located in a corresponding end slot space, by means of each end The slot space is used to limit the travel area of the magnetic lines of force, so that the magnetic lines of force concentrate to increase the magnetic flux density, and at the same time increase the back electromotive force to increase the thrust.

Specifically, the rotor structure of the built-in permanent magnet motor includes a core member having a center of curvature, and a plurality of recesses extending radially inward from the circumferential side of the core member at a predetermined angle, respectively. a plurality of end slots are respectively disposed on the portion of the core member corresponding to the end of each of the recessed ends of the slot, and each of the corresponding slots is connected, and the slot width is greater than the slot width of the connected slot, and a plurality of magnetic components, Each has a predetermined inherent length, each of which is embedded in each of the cavities, and has one end of the long axis extending into the corresponding end groove to have a predetermined extension length; wherein each of the members satisfies the following formula: 0<b/a≦1/2; Equation 2: 0<c<e; Equation 3: e=2d+c; in each formula, a is the inherent length of each of the magnetic members, and b is the extension of each of the magnetic members Into the length, c is the distance between adjacent two end slots, d is the distance between the groove wall of one end groove and the groove wall of one side of the groove, and e is the distance between adjacent two grooves .

Wherein, the depth of each of the end slots is greater than the length of each of the magnetic members.

Wherein each of the end slots is formed on the sides of the connected groove to form a shoulder of symmetrical width And the width of each of the shoulder faces is the d.

Wherein, the other end of the long axis of each of the magnetic members is immersed in a predetermined depth in the embedded recess.

In order to facilitate assembly and processing, the rotor structure of the built-in permanent magnet motor may further include a plurality of positioning bodies respectively protruding from the bottom wall of the corresponding end groove to abut the corresponding magnetic parts. On the end face.

The height of each of the positioning bodies is the difference between the depth of the corresponding end groove and the length of the extending.

(1a)‧‧‧Local areas

(1b)(2a)(3a)(4b)‧‧‧ Magnet

(2b)‧‧‧Rotor

(2c) ‧ ‧ empty slots

(2d) ‧ ‧ gap

(3b)(3c)‧‧‧ Shielded space

(4a) ‧‧‧Slots

(10) (10') ‧‧‧ rotor structure of built-in permanent magnet motor

(20) ‧‧‧ core pieces

(21)‧‧‧ Inner Ring Department

(30) (30’) ‧‧‧ slotted

(31) ‧ ‧ openings

(40) (40’) ‧‧‧ end slots

(41) ‧‧‧Slot wall

(50) (50') ‧ ‧ magnetic parts

(60’) ‧ ‧ positioning body

The first figure is a cross-sectional view of a conventional technique in which iron cores are composed of different materials.

The second figure is a cross-sectional view of a conventional technique in which a gap is formed between a magnetic member and a radially outer edge of the rotor.

The third figure is a cross-sectional view of a conventional technique in which a gap is formed between the magnetic member and the radially inner edge of the rotor.

The fourth figure is a magnetic line diagram of the prior art disclosed in the third figure.

The fifth figure is a cross-sectional view of another conventional technique in which a gap is formed between the magnetic member and the radially inner edge of the rotor.

Figure 6 is a cross-sectional view of a preferred embodiment of the present invention.

Figure 7 is a partial enlarged view of a portion of the sixth embodiment of the present invention along a sixth embodiment of the present invention.

The eighth figure is a magnetic line diagram of a preferred embodiment of the present invention.

Figure 9 is a partial cross-sectional view showing another preferred embodiment of the present invention.

First, referring to the sixth to eighth embodiments, in a preferred embodiment of the present invention, a rotor structure (10) of a built-in permanent magnet motor is provided, which is substantially in accordance with conventional radiation. The built-in permanent magnet motor of the (spoke) architecture is similar, mainly including a core member (20), a plurality of slots (30), a plurality of end slots (40) and a plurality of magnetic members (50).

The core member (20) is made of a magnetically permeable material such as a silicon steel sheet, and has a ring shape in addition to a center of curvature and an appropriate length extending in the axial direction.

Each of the cavities (30) is a straight groove having a suitable groove width, and is respectively radially extended from the circumferential side annulus of the radially outer edge of the core member (20) at equal angular intervals. Appropriate depth, the depth is less than the distance between the inner and outer diameters of the core member (20), so that the inner inner edge of the core member (20) retains a complete inner ring portion (21) of appropriate thickness to ensure the travel of the magnetic lines of force, and The width of the opening (31) of each of the cavities (30) on the circumferential side of the radially outer edge of the core member (20) is smaller than the width of the groove.

Each of the end slots (40) is a strip-shaped space having an isosceles trapezoidal shape, and is respectively disposed on the inner ring portion (21) of the core member (20), and each of them extends with a corresponding recessed groove (30). The ends are adjacent and connected, and the groove width of each end groove (40) is larger than the groove width of the adjacent communicating groove (30), and the correspondence between the adjacent end groove (40) and the groove (30) is made. The dimensions conform to the specific conditions described below.

Each of the magnetic members (50) is a sheet-like body of a suitable thickness, each having an inherent length, which is inserted into a corresponding recessed groove (30), and one end of the long shaft is immersed in the inserted recessed groove ( 30) in the opening (31), and spaced apart from the opening of the corresponding recessed groove (30), and the other end of the long axis extending from the recessed groove (30) into the adjacent end groove (40) ) A suitable extension length.

Wherein, the setting of each of the end slots (40) should satisfy the following formula: Equation 1: 0<b/a≦1/2.

Equation 2: 0 < c < e.

Equation 3: e=2d+c.

Among the various types:

a is the inherent length of each of the magnetic members (50).

b is the length of penetration of each of the magnetic members (50).

c is the separation distance between adjacent two end slots (40).

d is the distance between the groove wall (41) on the side of the end groove (40) and the groove wall (32) on the side of the groove (30).

e is the separation distance between adjacent two slots (30).

The rotor structure (10) of the built-in permanent magnet motor according to the present invention is formed by appropriately forming the magnetic poles at the other ends of the long axes of the magnetic members (50) by the end grooves (40). The magnetic resistance, as shown in the eighth figure, is such that the magnetic lines of force of each of the magnetic members (50) are concentrated in a limited portion of the core member (20) corresponding to the adjacent end grooves (40), thereby improving The magnetic flux density increases the back EMF, allowing the motor with the built-in permanent magnet motor rotor configuration (10) to achieve better thrust output.

In addition, since each of the magnetic members (50) is positioned by the embedded recesses (30), the smaller openings of the recesses (30) are provided, so that when the rotor is operated, It is avoided that each of the magnetic members (50) is released due to centrifugal force. Of course, in order to obtain further stable fixing effect, the conventional fixing technique of non-magnetic materials such as epoxy resin is filled in each end groove (40) space. In the space with each of the slots (31) of the recess (30), a better fixing effect is obtained.

Furthermore, due to the achievement of the main effects of the present invention, it is necessary to ensure that the other end of the long axis of the magnetic member (50) extends into the space type of the corresponding end slot (40) space, so that The manufacturing assembly is easy to implement, and the built-in permanent magnet motor rotor structure (10') provided in another preferred embodiment of the present invention as shown in FIG. 9 is compared with the prior embodiment. Department also contains a plurality of positioning bodies (60') respectively protruding from the bottom wall of the corresponding end groove (40'), and the height of each of the positioning bodies (60') and the depth of the corresponding end groove (40') and the extension The difference in length, so that each of the magnetic members (50') is inserted into the corresponding recess (30'), the other end of the long shaft is abutted against the top end of the corresponding positioning body (60') to obtain Positioning makes assembly of each of the magnetic members (50') easy.

(10) ‧‧‧Rotor construction of built-in permanent magnet motor

(20) ‧‧‧ core pieces

(30)‧‧‧Inlay

(40) ‧‧‧ end slots

(50)‧‧‧ Magnetic parts

Claims (6)

A rotor structure of a built-in permanent magnet motor includes: a core member having a center of curvature; and a plurality of slots extending radially inwardly from the circumferential side of the core member to a predetermined depth; The slots are respectively disposed on the portion of the core member corresponding to the end of each of the extending ends of the slot, and the corresponding slots are connected to each other, and the slot width is larger than the slot width of the connected slot; most of the magnetic components have The predetermined lengths are respectively embedded in the respective slots, and one end of the long shaft is extended into the corresponding end groove to have a predetermined extension length; wherein each of the members satisfies the following formula: Equation 1: 0<b /a≦1/2; Formula 2: 0<c<e; Equation 3: e=2d+c; in each formula, a is the inherent length of each of the magnetic members, and b is the extension length of each of the magnetic members. c is the distance between adjacent two end slots, d is the distance between the groove wall of one end groove and the groove wall of one side of the groove, and e is the distance between adjacent two grooves. The rotor structure of the built-in permanent magnet motor according to claim 1, wherein each of the end grooves has a depth greater than a length of each of the magnetic members. According to the rotor structure of the built-in permanent magnet motor according to the first aspect of the patent application, the system further includes a plurality of positioning bodies respectively protruding from a predetermined height of the groove bottom of the corresponding end groove. The rotor structure of the built-in permanent magnet motor according to claim 3, wherein the height of each of the positioning bodies is a difference between a depth of the corresponding end groove and the length of the extending end. The rotor structure of the built-in permanent magnet motor according to claim 1, wherein the long end of each of the magnetic members is immersed in a predetermined depth in the embedded recess. The rotor structure of the built-in permanent magnet motor according to claim 1, wherein each of the end grooves forms a shoulder surface of a symmetric width on both sides of the communicating groove, and the width of each of the shoulder faces For the d.