WO2017202321A1

WO2017202321A1 - Motor and electric vehicle

Info

Publication number: WO2017202321A1
Application number: PCT/CN2017/085593
Authority: WO
Inventors: 马冰青; 吴施汛; 齐文明
Original assignee: 比亚迪股份有限公司
Priority date: 2016-05-27
Filing date: 2017-05-23
Publication date: 2017-11-30

Abstract

A motor (1000) and an electric vehicle (2000). The motor (1000) comprises a housing (400), and comprises a motor rotor (300) and a motor stator (500) mounted in the housing. The motor rotor comprises a rotor core (310) made of an amorphous alloy material. The motor stator comprises a stator core made of a silicon steel material. The permanent magnet synchronous motor can provide a great power output by using a smaller size, and is particularly applicable to a driving motor running in an ultra-high speed in the electric vehicle.

Description

Motor and electric car

Technical field

The present invention relates to the field of motor technology, and in particular to an electric motor and an electric vehicle having the same.

Background technique

The motor is widely used in various fields as a drive unit. With the rise of electric vehicles in recent years, the importance of driving motors for driving vehicles is self-evident. Among them, it is known that a motor mainly includes a housing, a stator assembly, and a rotor assembly. For example, in some prior art, the outer casing includes a cylinder having an opening at the front end, a stator assembly is disposed in the outer casing, the stator assembly includes a stator core and a core winding, and the rotor assembly includes a rotating shaft, a permanent magnet and a rotor core; The core is set on the rotating shaft, and the rotor core is uniformly provided with a plurality of permanent magnets on the outer circumference; the front end of the outer casing is provided with an end surface, and the upper end of the outer casing is provided with a junction box to supply power to the winding. Thereby the rotary drive function of the motor is achieved. Among them, as a driving motor of an electric vehicle, power is required to be large and small, and how to solve this contradiction is also an important subject to be studied in the field.

Summary of the invention

An object of the present invention is to provide an electric motor and an electric vehicle having the same.

In order to achieve the above object, the present invention provides a motor including a housing, a motor rotor mounted in the housing, and a motor stator, the motor rotor including a rotor core made of an amorphous alloy material, the motor stator including Stator core made of silicon steel material.

The present invention also provides an electric vehicle including a drive motor, which is a motor provided by the present invention.

Through the above technical solution, the motor provided by the invention can provide a large power output in a small size, and is particularly suitable for a driving motor that operates at an ultra-high speed in an electric vehicle.

Other features and advantages of the invention will be described in detail in the detailed description which follows.

DRAWINGS

The drawings are intended to provide a further understanding of the invention, and are intended to be a In the drawing:

1 is a first perspective view of a motor according to an embodiment of the present invention;

2 is a second perspective view of a motor according to an embodiment of the present invention;

3 is an exploded perspective view of a motor according to an embodiment of the present invention;

4 is a schematic structural view of a rotor of a motor according to an embodiment of the present invention;

5 is a schematic structural view of a magnetic steel trough provided by an embodiment of the present invention, wherein in order to clearly show the angle, the angle is enlarged by several times when other features are unchanged;

Fig. 6 is a schematic structural view of an electric vehicle according to an embodiment of the present invention.

detailed description

The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative and not restrictive.

In the present invention, the orientation words such as "up, down, left, and right" are generally defined on the basis of the drawing direction of the drawing, and the "inside and outside" means correspondingly. Inside and outside of the contour of the part.

As shown in FIGS. 1 through 6, the present invention provides at least an electric motor rotor punch, an electric motor rotor, an electric motor 1000, and an electric vehicle 2000. The motor 1000 can be a two-pole motor, a permanent magnet synchronous motor, or a two-pole permanent magnet synchronous motor, and the motor of the present invention can also be other types of motors known in the art, such as an asynchronous motor or the like. In particular, an ultra-high speed motor, that is, a motor having a rotational speed of more than 20,000 rpm (revolutions per minute), the various motors mentioned in the present invention are also particularly suitable for use in a drive motor of an electric vehicle.

Here, the "two-pole" and "permanent magnet synchronization" as used in the present invention are terms well known in the art. For example, two pairs of poles mean that two pairs of magnetic poles are disposed on the rotor of the motor. Among them, the more the number of magnetic pole pairs, when the motor speed is high, especially when the motor in the present invention is an ultra-high speed motor, the higher the alternating frequency of the magnetic field, the more heat generated by the motor, and the requirements for the cooling system are also The higher the speed, the higher the iron consumption of the motor. Therefore, the two-pole motor is suitable for use in drive motors that operate at very high speeds. Of course, in other possible implementations, three pairs of poles or four pairs of poles may also be used.

In addition, the permanent magnet synchronous motor is also suitable for use in the drive motor of an electric vehicle. In terms of performance, it may include the advantages of high efficiency, high power factor, small volume, light weight, and low temperature rise. Specifically, for example, after a permanent magnet is embedded in a permanent magnet synchronous motor, a permanent magnet is used to establish a rotor magnetic field. When the rotor is in synchronous operation with the stator magnetic field during normal operation, there is no induced current in the rotor, and there is no rotor resistance loss. Greatly improve motor efficiency. In addition, when starting, the motor has a sufficiently large starting torque and does not require a large starting current, and is suitable for a driving motor driven by a power battery pack. In addition, the permanent magnet synchronous motor has high efficiency, the resistance loss in the rotor winding is low, and there is little or no reactive current in the stator winding, which makes the motor temperature rise low, and can also prolong the service life of the motor. The advantages brought by other permanent magnet synchronous motors are not described too much. In short, the permanent magnet synchronous motor has a simple structure, which makes the permanent magnet synchronous motor processing and distribution cost less, and the operation is more reliable. In addition, the permanent magnet synchronous motor uses the rare earth permanent magnet to increase the air gap magnetic density and raise the motor speed to The best, which significantly reduces the size of the motor, improves the power to mass ratio; in addition, because the excitation copper consumption is saved, the motor efficiency is significantly improved.

Structurally, as shown in FIG. 1 to FIG. 4, the motor provided by the embodiment of the present invention includes a housing 400 and is mounted thereon. Motor rotor 300 and motor stator 500 within housing 400. The motor stator 500 is fixedly disposed within the housing 400, and the motor rotor 300 is rotatably disposed at the center of the motor stator 500. The motor rotor 300 includes a rotor core 310 formed by stacking a plurality of rotor blades, and a rotating shaft 320 coupled to the rotor core 310. Specifically, in the present embodiment, the center of rotation of the punch body 100 of the rotor core is formed with a shaft hole 101, and a pair of keys 102 for cooperating with the rotating shaft, that is, a rotor, are symmetrically formed on the side wall of the shaft hole 101 The iron core 310 and the rotating shaft 320 are in a key connection manner. In other embodiments, the rotor core 310 and the rotating shaft 320 may also be connected by other transmission connections known to those skilled in the art, for example, using a non-circular cross-section connection. Further, an oil hole 103 may be formed in the rotor punch to form a part of the rotor oil passage, and the lubricating oil may be cooled by circulating the lubricating oil in the rotor.

In addition, the housing 400 has an end cover 800 away from the power output end. The end cover 800 may be formed with a bearing chamber. The inner end of the rotating shaft 320 is installed in the bearing chamber through the deep groove ball bearing 600, and protrudes from the outer end of the housing 400. It can be used as a power output. In addition, the junction box 700 mounted on the housing can be externally connected to a power source, for example, electrically connected to the power battery pack to be able to generate a magnetic field by supplying power to the winding 900, thereby enabling operation of the motor. In addition, an air gap is provided between the rotor and the stator of the motor to enable the motor to operate normally.

In an embodiment of the present invention, as shown in FIG. 4, the motor rotor blank provided includes a punch body 100 having a magnetic steel groove 200 for magnetic steel insertion formed thereon, that is, using magnetic steel as The permanent magnets form the rotor poles, that is, the permanent magnets in the embodiment adopt an embedded mounting manner, which can effectively ensure the stability of the rotor when rotating at an ultra-high speed, compared with the surface-mounted permanent magnet mounting method, embedded The permanent magnet mounting method is more suitable for rotors that operate at very high speeds. Among them, in the high-speed operation of the rotor, especially in the ultra-high speed operation, the magnetic steel accommodated in the magnetic steel tank will have a tendency to deform under the action of centrifugal force, that is, tensile stress is generated inside the magnetic steel, and at the same time, the pressure is resisted due to the resistance of the magnetic steel groove. Stress, in which the tensile strength of the magnetic steel is much lower than its compressive strength. In an embodiment of the magnetic steel, the tensile strength is only 85 MPa, and the compressive strength can be above 1000 MPa. The resulting tensile stress can affect the life of the magnetic steel. Based on this, in the present embodiment, in order to improve the life of the magnetic steel, the groove shape of the magnetic steel groove is improved, and the manner may include converting the tensile stress received by the magnetic steel into a compressive stress.

As shown in FIG. 5, the magnetic steel groove 200 has a straight groove section 201 and a dip angle section 202 on both sides of the straight groove section 201 along the surface direction of the punching body 100, and the dip angle section 202 is away from the center of rotation of the punching body 100. The first side edge is inclined outwardly from the end of the straight groove section 201, and the straight groove section 201 and the inclined section 202 on both sides of the straight groove section 201 together constitute a closed cross section of the magnetic steel groove 200 on the surface of the punching body 100. profile. As shown in FIG. 5, the closed cross-sectional profile of the magnetic steel groove 200 at the surface of the punch body 100 is divided by a broken line into a straight groove segment 201 and a dip segment 202. Thus, by providing an outwardly inclined dip angle section 202 on both sides of the straight groove section 201, a buffer zone for generating a slight deformation can be provided for both ends of the magnetic steel in the magnetic steel groove 200, that is, the magnetic steel is allowed to be magnetic when the rotor rotates. The steel groove 200 is slightly deformed to release the tensile stress generated inside the magnetic steel, which in turn increases the life of the magnetic steel.

Specifically, in the present embodiment, in order to realize the improvement of the magnetic steel groove 200, an angle can be formed on the existing one-shaped magnetic steel groove. In the present embodiment, the angle α between the first side edge of the inclined section 202 and the straight groove section 201 is 0.5 ° - 2 °, for example with a 1 ° tilt. It should be noted here that FIG. 5 is a view in which the angle α is enlarged several times in the case where other features are not changed, to clearly show the inclination section 202. This improvement in the magnetic steel tank 200 can effectively increase the life of the magnetic steel.

In the embodiment of the present invention, the punch body 100 is made of an amorphous alloy material, that is, the rotor core in the embodiment of the present invention is made of an amorphous alloy material, and the strength of the punch body 100 can be increased.

It is known that the tensile strength of the characteristics of the amorphous alloy material is several tens of times that of the ordinary silicon steel material, so that the improvement of the magnetic steel groove 200 causes the strength sacrificed by the punch body 100 to be compensated by the material, and its strength is greatly increased. It is higher than the strength of the rotor sheet of the prior art silicon steel material, thereby ensuring the life of the magnetic steel and ensuring the strength and life of the rotor core.

In addition, in the embodiment of the present invention, since the rotor core is made of an amorphous alloy material, the rotor core has the characteristics of high magnetic permeability, high electrical conductivity, small eddy current loss, and the like, and the performance of the motor is greatly improved. . Among them, it should be mentioned that the use of amorphous alloy material to make the rotor core can not only improve the rotor capacity, but also solve the key problem of how to achieve high power output through a small volume, enabling the drive motor in the electric vehicle field. Made great progress.

Specifically, the inventor of the present invention has a design idea that the inventors have found that in the field of electric vehicles, it is difficult to increase the volume of the motor due to the space layout, and thus it is difficult to increase the torque of the motor. In order to increase the power, according to the formula p=T*n/9550, it can be known that the output can be increased by increasing the rotational speed in a case where the volume is constant. Therefore, the inventors of the present invention have generated an incentive to use a motor having a small volume and a large number of revolutions as a drive motor of an electric vehicle. Among them, the inventors also considered that when the motor speed reached an ultra-high speed of 20,000 rpm, it was limited by the yield strength of ordinary silicon steel sheets, and the designed motor volume would be too small. When the motor volume is too small, although the rotation speed is high, it will directly affect the torque output of the motor, which cannot meet the requirements of the drive motor.

In view of these factors, the inventors of the present application have adopted an amorphous alloy material to form a rotor to solve the problem that the outer diameter of the rotor is limited, that is, to ensure that the motor can be operated at an ultra-high speed while increasing the volume of the motor as much as possible to increase the torque. Further increase the motor power. Further, the motor provided by the present invention does not simply manufacture all components using an amorphous alloy material. Except for the cost factor, the present invention also finds that under the current process conditions, the width of the amorphous alloy strip is limited. If the amorphous alloy strip is used as the motor stator, the produced motor is too small and affects the power of the motor. Output. In addition, since the magnetostriction coefficient of the amorphous alloy material is large, this will cause a large vibration noise of the motor. Therefore, the various motors provided by the embodiments of the present invention only make the rotor core made of amorphous alloy material, and the stator can be made of silicon steel material. Therefore, in the embodiment of the present invention, the rotor is made of an amorphous alloy material, and the stator is used. The structure of the original silicon steel material is the result of comprehensive consideration of various factors, and requires inventors to carry out a lot of creative labor.

Further, this coincides with the above-described idea of manufacturing a rotor core using an amorphous alloy material to improve the life of the magnetic steel at the time of ultrahigh speed operation. Thus, the present invention skillfully uses an amorphous alloy material for the manufacture of a rotor, which not only achieves the beneficial effect of improving the life of the magnetic steel during ultra-high speed operation, but also enables the designed motor to be small in size without being too small, that is, The use of amorphous alloy materials for the manufacture of rotor cores has also produced unexpected technical effects, achieving a variety of effects. Especially suitable for the requirements of high-power and small-volume drive motors, the performance of the drive motor has been greatly improved.

In the embodiment of the present invention, as shown in FIG. 5, in order to ensure uniform deformation on both sides of the magnetic steel, the two inclined sections 202 may be designed to be symmetrically disposed with respect to the central axis of the straight groove section 201. That is, the structure of the two dip segments 202 is substantially the same. In addition, in order to realize the structure of the magnetic steel, the second side edge of the inclined section 202 close to the center of rotation of the punch body 100 is arranged in line with the straight groove section 201. That is, only the first side edge line of the outer side of the inclined section is inclined with respect to the straight groove section 201, so that the magnetic steel can be slightly deformed outward at the two ends under the centrifugal force, and the magnetic steel can be better retained. In the magnetic steel tank 200. The first side edge and the second side edge of the angled section 202 are joined by a bent side edge to cooperate with the straight slot section 201 to form a closed cross-sectional profile. Specifically, further, in order to better adapt to the deformation of the magnetic steel, the length of the straight groove segment 201 may be designed to account for 1/2-3/4 of the length of the magnetic steel accommodated in the magnetic steel groove along the surface of the punching body 100. . Thereby, the deformation of the magnetic steel is better buffered, and the magnetic steel groove is prevented from exerting unnecessary destructive force on the magnetic steel.

The above describes the improvement in the groove type of the magnetic steel groove 200, and the improvement in the arrangement of the magnetic poles in the rotor piece of the motor in the embodiment of the present invention will be described below.

In order to form the rotor magnetic pole, as shown in FIG. 4, there are a plurality of magnetic steel grooves 200, and the plurality of magnetic steel grooves 200 are formed to obtain a magnetic steel groove group constituting a rotor magnetic pole, that is, the plurality of magnetic steel grooves 200 are formed. The magnetic steel groove group and the magnetic steel groove group constitute a rotor magnetic pole, wherein one magnetic steel groove group can form a rotor magnetic pole. Specifically, the magnetic steel groove group includes a first magnetic shape symmetrically arranged with respect to a first diameter of the punch body (as a case, the first diameter is a diameter in the vertical direction on the punch body 100, as shown in FIG. 4) The steel trough 210 and the second magnetic steel trough 220, the first magnetic steel trough 210 and the second magnetic steel trough 220 are arranged in a first V-shape that is open to the outside. In other words, the magnetic steel of the present invention is arranged in a V-shaped configuration. Also in order to generate a large magnetic field in a small size, in the present embodiment, the magnetic steel groove group further includes a third magnetic steel groove 230 and a fourth magnetic steel groove 240 symmetrically arranged with respect to the first diameter, the third The magnetic steel groove 230 and the fourth magnetic steel groove 240 are arranged in a second V-shape that is open to the outside and are spaced apart from the radially inner side of the first magnetic steel groove 210 and the second magnetic steel groove 220. That is, in the present invention, one magnetic pole may include four magnetic steels, thereby making full use of the space of the punching body, which is especially suitable for a small-sized driving motor. In order to optimize the layout of the four magnetic steels in the same group, the space is utilized reasonably, and optionally, the angle of the second V-shaped is smaller than the angle of the first V-shaped. In this way, the outer magnetic steel can better utilize the space in the chord direction of the punch body, so that the inner magnetic steel can better utilize the space in the radial direction of the punch body, the layout is more reasonable, and the magnetic field is generated more effectively.

In order to generate a uniform magnetic field, in the present embodiment, the plurality of magnetic steel groove groups are respectively configured to constitute a plurality of rotor magnetic poles, The plurality of magnetic steel groove groups are evenly distributed and uniformly distributed on the punch body in the circumferential direction. In the two-pole motor provided by the present invention, correspondingly, the magnetic steel groove group is four to constitute two pairs of poles of the motor rotor. In other embodiments, a different number of sets of magnetic steel slots may be provided depending on the number of pole pairs.

In the present embodiment, in order to ensure the strength of the punching body, the punching body 100 is formed with oil holes 103 uniformly distributed in the circumferential direction, and the oil holes 103 are located between adjacent magnetic steel groove groups to fully utilize the punching The sheet body space, in addition to the oil hole 103, can reduce the weight of the rotor and reduce the rotor moment of inertia. Further, in the present embodiment, the center of rotation of the punching main body 100 is formed with a rotating shaft hole 101, and a pair of keys 102 for engaging with the rotating shaft are symmetrically formed on the side wall of the rotating shaft hole 101, and the key 102 is convex toward the center of the circle And the pair of keys 102 are located on the first diameter. That is, the key is a convex structure rather than a concave structure, thereby facilitating the torque transmission in cooperation with the keyway on the rotating shaft.

In addition, in order to ensure the strength of the punch body, in the present embodiment, in the magnetic steel groove group, reinforcing ribs are disposed between the symmetrically arranged magnetic steel grooves to enhance the strength of the punch body. In addition, a magnetic bridge or a magnetic isolation hole is disposed between the magnetic steel groove and the edge of the punch body. The magnetic bridge can be as small as possible, which will reduce the magnetic flux leakage and increase the air gap magnetic density. In addition, the magnetic isolation hole can improve the air gap magnetic density waveform, thereby improving the performance of the motor.

The motor provided by the invention is more suitable for the driving motor of the electric vehicle, wherein the iron consumption is relatively low, the output power is improved, and the problem of large noise caused by the amorphous motor is avoided. The stator and rotor structures have been redesigned. Increasing the strength of the rotor structure can not only be made into an ultra-high-speed motor, but also has excellent electromagnetic performance. Only the rotor core uses an amorphous alloy, which reduces the processing difficulty and reduces the cost of the process. The volume of the motor is not limited by the amorphous alloy material, so that it can exert greater torque and power. At high speeds, the alternating frequency of the magnetic field is minimized, the iron loss is reduced, the heat dissipation is reduced, and the control of the motor is easily realized, so that the performance of the motor is significantly improved, and the performance of the electric vehicle is indirectly improved. More practical.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the embodiments described above, and various modifications may be made to the technical solutions of the present invention within the scope of the technical idea of the present invention. These simple variations are within the scope of the invention.

It should be further noted that the specific technical features described in the above specific embodiments may be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention has various possibilities. The combination method will not be described separately.

In addition, any combination of various embodiments of the invention may be made as long as it does not deviate from the idea of the invention, and it should be regarded as the disclosure of the invention.

Claims

An electric machine includes a housing (400), a motor rotor (300) mounted in the housing (400), and a motor stator (500), wherein the motor rotor includes an amorphous alloy material A rotor core (310) comprising a stator core made of a silicon steel material.
The motor according to claim 1, wherein said rotor core (310) is formed by stacking a plurality of rotor punches, said rotor blank comprising a punch body (100), said punch body (100) is formed with a magnetic steel groove (200) for magnetic steel insertion, the magnetic steel groove (200) being plural, the plurality of magnetic steel grooves (200) forming a magnetic steel groove group and the magnetic steel The slot group constitutes the rotor pole.
The motor according to claim 2, wherein said group of magnetic steel grooves comprises a first magnetic steel groove (210) and a second magnetic steel groove (220) symmetrically arranged with respect to a first diameter of said punch body The first magnetic steel trough (210) and the second magnetic steel trough (220) are arranged in a first V-shape that is open to the outside.
The motor according to claim 3, wherein said group of magnetic steel grooves further comprises a third magnetic steel groove (230) and a fourth magnetic steel groove (240) symmetrically arranged with respect to said first diameter, said The third magnetic steel trough (230) and the fourth magnetic steel trough (240) are arranged in a second V-shape that is open to the outside and are spaced apart from the first magnetic steel trough (210) and the second magnetic steel The radially inner side of the groove (220).
The motor according to claim 4, wherein the angle of the second V-shape is smaller than the angle of the first V-shape.
The motor according to any one of claims 2 to 5, wherein the plurality of magnetic steel groove groups are respectively configured to constitute a plurality of rotor magnetic poles, and the plurality of magnetic steel groove groups are even and circumferential The orientation is evenly distributed on the body of the punch.
The motor according to claim 6, wherein said punch body (100) is formed with oil holes (103) uniformly distributed in the circumferential direction, said oil holes (103) being located adjacent to said magnetic holes Between the steel trough groups.
The motor according to any one of claims 2-7, characterized in that the center of rotation of the punch body (100) is formed with a shaft hole (101), and the side wall of the shaft hole (101) is symmetrical Formed with a pair of keys (102) for mating with the rotating shaft, the keys (102) projecting toward the center of the circle and the pair of keys (102) are located at the first diameter on.
The motor according to claim 3 or 4, wherein in the group of magnetic steel grooves, reinforcing ribs are disposed between the symmetrically arranged magnetic steel grooves, and the magnetic steel grooves and the punching piece are A magnetic bridge or a magnetic isolation hole is disposed between the edges of the body.
The electric machine according to any one of claims 2-9, wherein the magnetic steel groove (200) has a straight groove section (201) along the surface direction of the punch body (100) and is located at the straight An inclined section (202) on both sides of the groove section (201), the first side edge of the inclined section (202) away from the center of rotation of the punching body (100) is from the end of the straight groove section (201) Tilt outside.
Motor according to claim 10, characterized in that the two angled sections (202) are arranged symmetrically about the central axis of the straight section (201).
The electric machine according to claim 10 or 11, characterized in that the angle between the first side edge of the angled section (202) and the straight groove section (201) is 0.5°-2°.
The electric machine according to claim 10 or 11, wherein the second side edge of the inclined section close to the center of rotation of the punch body (100) is collinearly arranged with the straight groove section (201).
The motor according to claim 10 or 11, wherein said straight groove section (201) occupies 1/ of the length of the magnetic steel accommodated in said magnetic steel groove along the surface of said punch body (100) 2-3/4.
The electric machine according to any one of claims 1 to 14, wherein the motor rotor (300) further comprises a rotating shaft (320) coupled to the rotor core (310), the rotating shaft (320) The inner end is mounted by a deep groove ball bearing (600) on which a junction box (700) is mounted.
A machine according to any one of claims 1 to 15, wherein the motor is an ultra high speed motor.
An electric vehicle comprising a drive motor, characterized in that the drive motor is a motor according to any one of claims 1-16.