CN114498977A - A rotor iron core, rotor, motor, motor drive system and electric vehicle - Google Patents

Abstract

The embodiments of the present application relate to a rotor iron core, a rotor, a motor, a motor drive system and an electric vehicle. The rotor iron core includes a rotor body and a sleeve, the iron core base in the rotor body is arranged with a plurality of iron core accessories along the circumferential direction, a first rotor slot is respectively formed between the iron core base and each iron core accessory, and the rotor body The additional sleeve is used to strengthen the mechanical strength of the rotor body and realize the high-speed operation of the rotor. There is no need to set a relatively thick magnetic bridge between the iron core base and the iron core accessories to reduce the magnetic flux leakage, and the direction of the magnetic field lines is adjusted through the magnetic isolation slot to reduce the magnetic flux leakage, without considering the magnetic bridge when the rotor rotates at high speed. Risk of easy breakage. Under the same rotor outer diameter and the same built-in form and size of permanent magnets, the motor of the present application can achieve a higher rotational speed and achieve a higher power density. The synchronous reluctance motor and the permanent magnet-assisted synchronous reluctance motor using the above-mentioned rotor core can also achieve higher speed operation and improve the power density of the motor.

Description

A rotor iron core, rotor, motor, motor drive system and electric vehicle

technical field

The embodiments of the present application relate to the field of motors, and in particular, to a rotor iron core, a rotor, a motor, a motor drive system, and an electric vehicle.

Background technique

In some application scenarios, the motor needs to reach a very high speed, which will bring greater challenges to the motor structure. Taking the built-in permanent magnet motor commonly used in electric vehicles as an example, there is usually a magnetic bridge on the rotor core for strength support. Higher motor speed will bring greater centrifugal force to the rotor, and the magnetic bridge has the risk of stress concentration and fatigue fracture. In order to reduce the risk of damage to the magnetic bridge caused by higher rotation speed, a relatively thick magnetic bridge can be set, but it will increase the risk of magnetic flux leakage of the motor, and reduce the electromagnetic performance such as torque, power factor and efficiency. In order to increase the speed of the motor, more permanent magnets can be arranged on the rotor core, but the space for thickening the magnetic bridge on the rotor core becomes less, and the thinner magnetic bridge is difficult to face the risk of fracture, thus limiting the increase the motor speed. When the permanent magnet motor in the industry requires a high speed, it is difficult to take into account the mechanical strength and electromagnetic performance of the magnetic bridge, and it is difficult to further increase the motor speed by only thickening the magnetic bridge.

SUMMARY OF THE INVENTION

The embodiments of the present application provide a rotor iron core, a rotor, a motor, a motor drive system and an electric vehicle, which solve the problem that when the motor in the prior art requires a high rotational speed, it is difficult to take into account the mechanical strength and electromagnetic performance of the magnetic bridge, and only through the It is difficult to further increase the motor speed by thickening the magnetic bridge.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical solutions:

In a first aspect, embodiments of the present application provide a rotor core, including a rotor body and a sleeve. The rotor body includes an iron core base body and a plurality of iron core accessories, the iron core base body is used for connecting with the rotating shaft, and the plurality of iron core accessories are distributed along the circumference of the iron core base body. A first rotor slot is respectively formed between the iron core base and each iron core accessory, and at least a part of each first rotor slot is formed with a magnetic isolation slot for reducing magnetic flux leakage. The sleeve is sleeved on the outer edges of the plurality of iron core accessories.

In the rotor iron core provided by the embodiment of the present application, the iron core base in the rotor body is arranged with a plurality of iron core accessories in the circumferential direction, and a first rotor slot is respectively formed between the iron core base and each iron core accessory. The additional sleeve is used to strengthen the mechanical strength of the rotor body and realize the high-speed operation of the rotor. There is no need to set a relatively thick magnetic bridge between the iron core base and the iron core accessories to reduce the magnetic flux leakage, and the direction of the magnetic field lines is adjusted through the magnetic isolation slot to reduce the magnetic flux leakage, and there is no need to consider the magnetic bridge when the rotor rotates at high speed. Risk of easy breakage. Comparing the conventional motor and the built-in permanent magnet motor using the above-mentioned rotor iron core, under the same rotor outer diameter, the same permanent magnet built-in form and size, the motor of the present application can achieve a higher speed and achieve a higher power density . The synchronous reluctance motor and the permanent magnet-assisted synchronous reluctance motor using the above-mentioned rotor core can also achieve higher speed operation and improve the power density of the motor.

The motor is applied to the driving motor of the electric vehicle, and the power of the driving motor is transmitted to the driving wheel of the electric vehicle through the reducer, and the reducer plays the role of reducing the speed and increasing the torque. The simulation test is carried out on the application of the conventional motor and the motor of the present application in the electric vehicle, using the same outer diameter of the rotor, the same built-in form and size of the permanent magnet, and the same high speed, and obtained through simulation analysis: compared with the conventional motor, the rotor in the motor of the present application is The axial size of the iron core can be made smaller, that is, the volume of the motor can be made smaller, and the power of the motor can be higher, thereby achieving an increase in power density. Under the condition that the assembly space of the drive motor and the reducer in the electric vehicle is certain, after the motor volume of the present application is made small, the volume of the reducer can be made larger, and the reducer has a larger speed ratio. After the motor of the present application is configured with a reducer with a larger speed ratio, the wheel torque of the driving wheel can be increased, so that the electric vehicle has better dynamic performance.

In combination with the first aspect, in the first possible implementation manner of the first aspect, the iron core base and the plurality of iron core accessories in the rotor body are separate structures, and the rotor body is not provided with a magnetic bridge, which is not a conventional built-in type. Permanent magnet motors use an integral rotor core punch. The iron core base body and a plurality of iron core accessories can be fixed together by a sleeve, which improves the overall structural strength and enables the rotor to withstand higher rotational speeds.

In combination with the first aspect, in a second possible implementation manner of the first aspect, a magnetic bridge is provided in the first rotor slot, the magnetic bridge is used to connect the iron core base and the iron core accessories, and the thickness of the magnetic bridge is less than or equal to 1mm . In this embodiment, the thickness of the magnetic bridge is extremely small, and it is only used to connect the iron core base and the iron core accessories when processing the rotor body, so as to facilitate the pick-and-place and assembly operations of the rotor body workpiece after stamping. When the rotor of this embodiment rotates, the magnetic bridge may be broken. Due to the sleeve structure outside the rotor, the overall strength of the rotor will not be affected.

With reference to any one of the first aspect to the second possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the rotor body is in a sheet shape, and the number of the rotor The rotor bodies are arranged in layers, and the iron core accessories in different rotor bodies are arranged in layers. Multiple stacked rotor bodies are easily formed and assembled.

With reference to the third possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, the multiple iron core accessories arranged in layers are connected by fasteners, and the fasteners pass through different rotor bodies Locating holes for multiple core attachments at the same location. Fasteners can include long bolts and nuts, the long bolts are passed through the positioning holes of a plurality of iron core accessories, and nuts are screwed on the ends of the long bolts to fix the iron core accessories on the same axis together, the assembly The method is easy to operate, the connection is reliable, and the strength of the rotor can be improved.

In combination with the third possible implementation manner of the first aspect, in the fifth possible implementation manner of the first aspect, a plurality of iron core accessories arranged in layers are connected by injection molding parts, and the injection molding parts are filled with the same rotor body on different rotor bodies. A first rotor slot of a plurality of iron core attachments. The plurality of rotor bodies are assembled, and the partial regions of the first rotor grooves of the plurality of laminated iron core accessories are filled with thermal plastic, and after the temperature is lowered, an injection molded part is formed, and the plurality of iron core accessories are reliably connected together.

In combination with the third possible implementation manner of the first aspect, in the sixth possible implementation manner of the first aspect, a plurality of iron core accessories arranged in layers are connected by buckle pieces, and the buckle pieces are buckled on different rotor bodies at the same time. Snap-in slots for multiple core attachments in one location. The plurality of iron core accessories can be fixed together by arranging the buckle pieces in the buckle grooves of the aligned plurality of iron core accessories.

With reference to any one of the third possible implementation manner to the sixth possible implementation manner of the first aspect, in the seventh possible implementation manner of the first aspect, the position of the positioning hole of the iron core attachment is determined by the iron core. The axis of symmetry of the attachment is determined to be offset by a predetermined angle around the center of the rotor body, and two adjacent rotor bodies are stacked in positive and reverse directions, so that the positioning holes of the two overlapping iron core attachments are arranged in line. By reusing the same sheet-shaped rotor body, two adjacent rotor bodies are made to be stacked upside down, and permanent magnets are respectively arranged in the rotor slots of each rotor body. The two adjacent permanent magnets in the rotor axis are not completely overlapped but staggered. At a certain angle, the rotor skew effect can be achieved, the torque fluctuation of the motor can be reduced, and the noise, vibration and acoustic and vibration roughness performance of the motor during operation can be improved.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in the eighth possible implementation manner of the first aspect, the first rotor slot is in a line shape, and all the first rotor slots have a The center extension can enclose a convex polygon. The middle position of each first rotor slot is used for installing permanent magnets, and magnetic isolation slots are respectively formed at both ends of the first rotor slot.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in a ninth possible implementation manner of the first aspect, the first rotor slot is V-shaped, and the inner portion of the first rotor slot is V-shaped. The concave side is disposed away from the center of the rotor body. The first rotor slot includes two sections of first sub-slots arranged in a V shape, the middle position of each first sub-slot is used to install permanent magnets, and the two ends of the first rotor slot and the two first sub-slots are close to each other. The positions respectively form magnetic isolation grooves.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in a tenth possible implementation manner of the first aspect, the first rotor slot is V-shaped, and the inner portion of the first rotor slot is V-shaped. The concave side is arranged away from the center of the rotor body; the iron core attachment has a second rotor slot in a line shape, and the center extension lines of all the second rotor slots can enclose a convex polygon. A zigzag second rotor slot is added to the iron core attachment, the first rotor slot is used as an inner layer slot and the second rotor slot is used as an outer layer slot.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in an eleventh possible implementation manner of the first aspect, the first rotor slot is V-shaped, and the first rotor slot has a V-shape. The concave side is arranged away from the center of the rotor body; the iron core attachment has a V-shaped second rotor slot, and the inner concave side of the second rotor slot is arranged away from the center of the rotor body.

A V-shaped second rotor slot is added to the iron core attachment. The second rotor slot includes two second sub-slots arranged in a V-shape. The first rotor slot is used as the inner layer slot and the second rotor slot is used as the outer layer. groove.

The above four rotor slot implementation methods are suitable for the rotor structure of the built-in permanent magnet motor. The first rotor slots are all installed with permanent magnets, and a magnetic isolation slot is formed in part of the first rotor slot to reduce magnetic flux leakage. predetermined magnetic circuit.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in the twelfth possible implementation manner of the first aspect, the first rotor slot is in a U-shape composed of a plurality of straight segments Type, the concave side of the first rotor slot is disposed away from the center of the rotor body.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in a thirteenth possible implementation manner of the first aspect, the first rotor slot is in a U-shape composed of a plurality of straight segments The inner concave side of the first rotor slot is set away from the center of the rotor body; the iron core attachment has a second rotor slot, the second rotor slot is U-shaped composed of multiple straight segments, and the inner concave side of the second rotor slot is The side faces away from the center of the rotor body. One or more second rotor slots are added to the core attachment, the first rotor slot serving as an inner slot and the second rotor slot serving as an outer slot.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in the fourteenth possible implementation manner of the first aspect, the first rotor slot is arc-shaped, and the inner portion of the first rotor slot is in an arc shape. The concave side is disposed away from the center of the rotor body.

With reference to any one of the first aspect to the seventh possible implementation manner of the first aspect, in a fifteenth possible implementation manner of the first aspect, the first rotor slot is arc-shaped, and the inner portion of the first rotor slot is in an arc shape. The concave side is arranged away from the center of the rotor body; the iron core attachment has an arc-shaped second rotor slot, and the inner concave side of the second rotor slot is arranged away from the center of the rotor body. One or more second rotor slots are added to the core attachment, the first rotor slot serving as an inner slot and the second rotor slot serving as an outer slot.

One of the last four rotor cores is used, and rotor slots (a first rotor slot, a second rotor slot) are arranged on the rotor body. Permanent magnets may not be arranged in the rotor slots, and the rotating shaft is passed through and fixed to the rotor core. , the rotor of the synchronous reluctance motor is obtained, and a predetermined magnetic circuit can be formed on the rotor iron core.

One of the last four rotor cores is used. After setting rotor slots (first rotor slot and second rotor slot) on the rotor body and adding permanent magnets, the rotating shaft is passed through and fixed to the rotor core to obtain permanent magnets. The rotor of the auxiliary synchronous reluctance motor can form a predetermined magnetic circuit on the rotor iron core. The volume of the permanent magnets used in the permanent magnet-assisted synchronous reluctance motor using the last four rotor cores can be set smaller, and the reluctance loop is more obvious, thereby increasing the rotor reluctance torque component.

With reference to any one of the first aspect to the fifteenth possible implementation manner of the first aspect, in the sixteenth possible implementation manner of the first aspect, the sleeve is a carbon fiber sleeve, a steel sleeve or an alloy steel sleeve. By arranging a sleeve on the rotor body, the mechanical strength of the rotor structure is improved, so that the rotor can run reliably at high speed.

In combination with any one of the sixteenth possible implementation manners of the first aspect to the first aspect, in the seventeenth possible implementation manner of the first aspect, the iron core base is a non-oriented silicon steel piece, and the iron core accessories are For oriented silicon steel parts, the magnetization orientation of the core attachment is the direction from the inner edge to the outer edge of the core attachment. After adopting the iron core accessories made of grain-oriented silicon steel, the magnetic flux leakage in the area of the iron core accessories is effectively reduced, thereby improving the electromagnetic performance. Under the same alternating electromagnetic field, the losses generated by the core attachment will decrease. Alternatively, it is also feasible that both the iron core base and the iron core accessories are non-oriented silicon steel parts.

With reference to any one of the first aspect to the seventeenth possible implementation manner of the first aspect, in the eighteenth possible implementation manner of the first aspect, the outer periphery of the iron core base has a circumferential direction along the iron core base There are a plurality of distributed installation positions, and a plurality of iron core accessories are set in the plurality of installation positions in one-to-one correspondence. The iron core base body forms an outer convex portion between two adjacent installation positions, and the outer convex portion is used to connect with the inner wall of the sleeve. Abut. When assembling the sleeve, the inner wall of the sleeve abuts against the outer edge of each iron core accessory and each outer convex portion of the iron core base, so as to reliably fix the iron core base and each iron core accessory together.

With reference to any one of the first aspect to the seventeenth possible implementation manner of the first aspect, in the nineteenth possible implementation manner of the first aspect, the outer periphery of the core base has a circumferential distribution along the iron core base There are multiple installation positions, a plurality of iron core accessories are set in the multiple installation positions in one-to-one correspondence, the iron core base body forms a first surface between two adjacent installation positions, and the first surface and the inner wall of the sleeve are arranged at intervals, The mounting position can accommodate a variety of core accessories with different outer diameters. The installation position of the iron core base can be compatible with iron core accessories of different arc outer diameters within a certain range, and the outer diameter of the rotor can be adjusted to adapt to motors of different specifications, realize platform design, and reduce production costs.

In a second aspect, embodiments of the present application provide a rotor, including a rotating shaft, a permanent magnet, and a rotor core as described in the nineteenth possible implementation manner of the first aspect to the first aspect, the rotating shaft passing through and being fixed to The rotor iron core, the permanent magnets are installed in the rotor iron core.

In a third aspect, embodiments of the present application provide a rotor, including a rotating shaft and a rotor core as described in the twelfth possible implementation manner to the fifteenth possible implementation manner of the first aspect, the rotating shaft passing through and Fixed to the rotor core.

In a fourth aspect, embodiments of the present application provide a motor, including a stator and the rotor as described in the second or third aspect, the stator is sleeved on the outer circumference of the sleeve, and an air gap is formed between the stator and the rotor. The motor may be a built-in permanent magnet motor, a synchronous reluctance motor, or a permanent magnet assisted synchronous reluctance motor.

In a fifth aspect, an embodiment of the present application provides a motor drive system, including a controller and the motor described in the fourth aspect, and the controller and the motor are electrically connected. The controller is used to adjust the output torque of the motor to realize the functions of idling, acceleration and energy recovery of the motor.

In a sixth aspect, embodiments of the present application provide an electric vehicle, including the motor drive system described in the fifth aspect. The electric vehicle may be an electric vehicle, a subway train, a high-speed EMU, and the like.

Description of drawings

Fig. 1 is the partial structure diagram of the double V-shaped rotor in the conventional technology;

2 is a schematic structural diagram of a rotor provided by an embodiment of the present application;

3 is an exploded schematic view of the rotor of FIG. 2;

4 is a schematic structural diagram of a rotor provided by another embodiment of the present application;

(a) and (b) in FIG. 5 are respectively a three-dimensional assembly view and a cross-sectional view along the A-A line of the rotor as the first comparative example;

6 is a schematic structural diagram of a rotor as a second comparative example;

7 is a schematic structural diagram of a rotor as a third comparative example;

FIG. 8 is a schematic structural diagram of a rotor as a fourth comparative example;

(a), (b), and (c) in FIG. 9 are respectively schematic partial structural diagrams of rotors provided by different embodiments of the present application when magnetic bridges are provided;

10 is a perspective assembly view of a rotor provided by another embodiment of the application;

Figure 11 is an exploded perspective view of the rotor of Figure 10;

Figure 12 is a cross-sectional view along line B-B of Figure 10;

13 is a perspective assembly view of a rotor provided by another embodiment of the application;

14 is a schematic structural diagram of a rotor provided by another embodiment of the application;

Figure 15 is an exploded schematic view of the rotor of Figure 14;

16 is a schematic structural diagram of a rotor provided by another embodiment of the application;

(a) to (e) in FIG. 17 are respectively partial structural schematic diagrams of rotors provided by different embodiments of the present application;

18 is a schematic structural diagram of a rotor provided by another embodiment of the application when the iron core attachment is an oriented silicon steel part;

(a) and (b) in FIG. 19 are respectively schematic structural diagrams of the rotor before and after removing the outer convex portion according to another embodiment of the present application;

20 is a schematic structural diagram of a rotor provided by another embodiment of the application;

FIG. 21 is a schematic structural diagram of the rotor of FIG. 20 when the front and back sides are stacked.

Detailed ways

Compared with asynchronous motors, permanent magnet motors provide excitation with permanent magnets, without excitation current and without excitation loss, which can improve the efficiency and power density of the motor. Permanent magnet motors can be used as drive motors for electric vehicles. A permanent magnet motor includes a stator and a rotor. The stator is made of laminations, which can reduce the iron loss when the motor is running. The stator is installed with three-phase AC windings for generating the stator rotating magnetic field. The rotor can be made of solid or laminated by lamination, the rotor is equipped with permanent magnets, and the permanent magnets are used to generate the rotor magnetic field.

According to the different positions of the permanent magnets on the motor rotor, permanent magnet motors are divided into surface-mounted permanent magnet machines (SPM) and inserted permanent magnet machines (IPM). In a surface-mounted permanent magnet motor, the permanent magnets are attached to the surface of the rotor core. Referring to FIG. 1 , in the built-in permanent magnet motor, the permanent magnets 1 are embedded inside the rotor iron core 2 , and the rotor iron core 2 has rotor slots 2 a for installing the permanent magnets 1 . The built-in form of the permanent magnet 1 can be divided into inline shape, single V, double V, V+one and so on. Figure 1 shows the structure of a conventional double V rotor. Compared with the surface-mounted permanent magnet motor, the rotor magnetic circuit of the built-in permanent magnet motor is asymmetric, which will generate reluctance torque during operation, which can improve the power density and overload capacity of the motor, and it is easier to achieve weak field speed expansion. When the permanent magnet motor is used as a motor, the three-phase current is passed into the three-phase AC winding of the stator, the stator generates a rotating magnetic field, and the rotor magnetic field interacts with the stator rotating magnetic field to generate an electromagnetic torque on the rotor to drive the rotor to rotate.

On the rotor iron core of a conventional motor, a magnetic bridge 2b is provided between two adjacent rotor slots 2a of the rotor iron core 2 or between the rotor slot 2a and the outer peripheral surface of the rotor iron core 2. The long magnetic bridge 2b uses It is used for the passage of magnetic force lines, and plays the role of reducing magnetic flux leakage when the magnetic force lines of the magnetic bridge 2b reach saturation. The smaller the thickness of the magnetic bridge 2b, the more saturated the magnetic field lines of the magnetic bridge 2b, and the better the effect of reducing magnetic flux leakage. The longitudinal direction X and the thickness direction Y of the magnetic bridge 2b are both on the plane of the rotor core 2, and they are perpendicular to each other. The magnetic bridge 2b needs to meet a certain thickness to overcome the fatigue fracture damage of the magnetic bridge 2b caused by centrifugal force when the rotor rotates at a high speed.

In motor design, it is usually hoped that the higher the power density, the better. The power density is the ratio of the motor output power to the volume of the motor's conductive and magnetic material, and the motor output power is the product of the speed and the torque. Therefore, improving the motor torque density and speed can Improve motor power density. Under a certain material and process level, the torque density of a conventional motor is constant, that is, the larger the motor volume or outer diameter, the greater the torque. In order to pursue higher motor power density, it is necessary to rely on higher motor speed. At present, the speed of the drive motor used for electric vehicles reaches more than 16000rpm. In some occasions where the assembly space is very strict, the motor volume needs to be made smaller. In the case of keeping the motor power unchanged, it is necessary to further increase the motor speed. Reach above 20000rpm.

The conventional motor adopts a large outer diameter structure at high speed, and the rotor stress will exceed the material yield strength, which limits the further increase of the motor speed or power. Exemplarily, in a conventional motor, the rotor is made of laminated silicon steel sheets. The yield strength of the silicon steel sheet material is about 450MPa, which will be lower at high temperatures. After the motor speed is above 20,000rpm, consider the safety margin of the speed, and the outer diameter is 130mm. The stress at the weak position of the rotor (that is, the magnetic bridge) usually exceeds 460MPa, and the magnetic bridge is prone to fatigue fracture. In order to further increase the speed, by reducing the outer diameter of the rotor, the stress at the weak position of the rotor can be made below the yield strength of the material, and the motor torque will be reduced. Therefore, it is difficult for a conventional motor to take into account both the high rotational speed and the high torque of the motor.

FIG. 2 is a schematic structural diagram of a rotor provided by an embodiment of the application; FIG. 3 is an exploded schematic diagram of the rotor of FIG. 2 ;

FIG. 4 is a schematic structural diagram of a rotor provided by another embodiment of the present application.

Referring to FIGS. 2 to 4 , an embodiment of the present application provides a rotor core 100 , which includes a rotor body 110 and a sleeve 120 . The rotor body 110 includes an iron core base 111 and a plurality of iron core accessories 112. The iron core base 111 is used to connect with the rotating shaft (not shown in the figure), and the plurality of iron core accessories 112 are distributed along the circumferential direction of the iron core base 111. The iron core accessories 112 as the part not directly connected to the shaft. A first rotor slot 113 is respectively formed between the iron core base 111 and each iron core attachment 112 , and at least a part of each first rotor slot 113 is formed with a magnetic isolation slot 1131 for reducing magnetic flux leakage. The sleeve 120 is sleeved on the outer edges 112 b of the plurality of iron core accessories 112 .

The outer edge 112 b of the iron core attachment 112 refers to the outermost edge of the iron core attachment 112 away from the rotor body 110 . The iron core base body 111 and the plurality of iron core accessories 112 in the rotor body 110 may be made solid, respectively. Alternatively, a plurality of rotor bodies 110 are arranged in layers, and each rotor body 110 includes a sheet-shaped iron core base 111 and a plurality of sheet-shaped iron core accessories 112. After the plurality of rotor bodies 110 are assembled, the plurality of iron cores The core bases 111 are stacked in sequence, and a plurality of iron core accessories 112 are stacked in sequence at different circumferential positions of the core base 111 .

In the rotor iron core 100 provided by the embodiment of the present application, the iron core base body 111 in the rotor body 110 is arranged with a plurality of iron core accessories 112 in the circumferential direction, and a second iron core base body 111 and each iron core accessory 112 are respectively formed A rotor slot 113, and a sleeve 120 is added to the rotor body 110 to strengthen the mechanical strength of the rotor body 110, so as to realize the high-speed operation of the rotor. There is no need to set a relatively thick magnetic bridge for reducing magnetic flux leakage between the iron core base 111 and the iron core attachment 112, and the magnetic field lines are adjusted through the magnetic isolation slot 1131 to reduce the magnetic flux leakage, without considering the magnetic bridge at high rotor speed. There is a risk that the magnetic bridge is prone to breakage. Comparing the conventional motor and the built-in permanent magnet motor using the above-mentioned rotor iron core 100, the motor of the present application can reach a higher speed and achieve a higher power under the same rotor outer diameter, the same permanent magnet built-in form and size density. The synchronous reluctance motor and the permanent magnet-assisted synchronous reluctance motor using the above-mentioned rotor core 100 can also achieve higher rotational speed operation and improve the power density of the motor.

Exemplarily, in the conventional motor and the motor of the present application, the rotor iron core 100 is formed by laminating silicon steel sheets, and the outer diameter of the rotor is both 130 mm. Under the condition that the mechanical strength of the rotor is satisfied, the rotor speed in the conventional motor can only reach 18000rpm. When the rotor speed reaches more than 20000rpm, the magnetic bridge stress in the rotor will exceed the yield strength of the material and break down. In the rotor iron core 100 of the present application, under the condition that the mechanical strength of the rotor iron core 100 is satisfied, the rotational speed of the rotor can reach more than 25,000 rpm. It can be seen that the motor using the rotor iron core 100 of the present application can reach a higher rotational speed and achieve a higher power density.

With the same rotor outer diameter and the same permanent magnet built-in form and size, compared with the method of thickening the magnetic bridge to achieve a higher speed of the rotor, the rotor core 100 of the present application uses the sleeve 120 to improve the mechanical strength of the rotor body 110, The permanent magnets 200 can be further approached in the direction of the air gap to strengthen the interaction between the rotor magnetic field and the stator magnetic field, thereby improving the performance of the motor or reducing the cost of the motor.

The simulation test is carried out on the conventional motor and the motor using the rotor iron core of the application, using the same outer diameter of the rotor, the same built-in form and size of the permanent magnet, and the same high speed, and obtained through simulation analysis: compared with the conventional motor, the application of the rotor iron The torque and power of the motor of the core are relatively high, which can take into account the high speed and high torque of the motor.

The motor is applied to the drive motor of the electric vehicle, and the power of the drive motor is transmitted to the driving wheel of the electric vehicle through a reducer (such as a gear reducer), and the reducer plays the role of reducing the speed and increasing the torque. The simulation test is carried out on the application of the conventional motor and the motor of the present application in the electric vehicle, using the same outer diameter of the rotor, the same built-in form and size of the permanent magnet, and the same high speed, and obtained through simulation analysis: compared with the conventional motor, the rotor in the motor of the present application is The axial size of the iron core can be made smaller, that is, the volume of the motor can be made smaller, and the power of the motor can be higher, thereby achieving an increase in power density. Under the condition that the assembly space of the drive motor and the reducer in the electric vehicle is certain, after the motor volume of the present application is made small, the volume of the reducer can be made larger, and the reducer has a larger speed ratio. After the motor of the present application is configured with a reducer with a larger speed ratio, the wheel torque of the driving wheel can be increased, so that the electric vehicle has better dynamic performance. Among them, the wheel side torque of the driving wheel is equal to the product of the motor torque and the speed ratio of the reducer.

(a) and (b) of FIG. 5 are a perspective assembly view and a cross-sectional view along the A-A line of the rotor as the first comparative example, respectively.

In the rotor as the first comparative example, referring to (a) and (b) of FIG. 5 , the rotor includes a plurality of disk-shaped permanent magnets 11 arranged in the axial direction, and sleeves sleeved on the outer circumference of each disk-shaped permanent magnet 11 . The barrel 12 , and a plurality of connecting rods 13 extending along the axial direction of the sleeve 12 , and the plurality of connecting rods 13 are arranged on the outer wall of the sleeve 12 or on the inner wall of the sleeve 12 . The cooperation of the plurality of connecting rods 13 and the sleeve 12 can strengthen the strength of the rotor, so that the rotor can reach a higher working speed. However, the rotor of the first comparative example is only suitable for small motors, and is not suitable for electric vehicle drive motors or other large motor scenarios, because the structure in which the plurality of connecting rods 13 are connected to the sleeve 12 is unreliable, and the air gap is occupied. The size will increase, reducing the electromagnetic performance. The rotor adopts an integral disc-shaped permanent magnet 11, which is essentially a surface-mounted permanent magnet motor. The surface-mounted permanent magnet motor has a weak high-speed field-weakening speed expansion capability, which is difficult to meet the needs of electric vehicles or other scenarios with a wide speed operating range. The deformation mode of the first comparative example rotor is investigated, and the rotor is replaced with a built-in permanent magnet motor structure, which is difficult to solve the problem of insufficient magnetic bridge strength of the built-in permanent magnet motor at high speed.

Compared with the rotor of the first comparative example, the connecting rod 13 is arranged on the sleeve 12. Referring to FIG. 2 to FIG. 4, the rotor using the rotor core 100 of the present application is sleeved outside the rotor body 110 through the sleeve 120, which is more structurally. It is reliable and occupies a small size of the air gap, which is conducive to improving electromagnetic performance, so that the motor using the rotor core 100 of the present application is suitable for large motors, electric vehicle drive motors or other large motor scenarios. The rotor core 100 of the present application is suitable for a built-in permanent magnet motor, has good high-speed field-weakening speed expansion capability, and meets the needs of electric vehicles or other scenarios with a wide speed operating range. Compared with the deformation mode of the rotor of the first comparative example, the rotor core 100 of the present application adds a sleeve 120 to the rotor body 110 to strengthen the mechanical strength of the rotor body 110 and realize the high-speed operation of the rotor, without considering the magnetic field when the rotor is at a high speed. Risk of easy breakage of the magnetic bridge.

FIG. 6 is a schematic structural diagram of a rotor as a second comparative example.

In the rotor as the second comparative example, referring to FIG. 6 , the rotor includes a plurality of axially arranged disk-shaped permanent magnets 21 , a rotating shaft 22 passing through each disk-shaped permanent magnet 21 , a rotating shaft 22 sleeved on each disk-shaped permanent magnet 21 A steel sleeve 23 on the outer periphery, and a carbon fiber sleeve 24 sleeved on the outer periphery of the steel sleeve 23 . The steel sleeve 23 is used as the inner sheath, and the carbon fiber sleeve 24 is used as the outer sheath. When the rotor rotates, the centrifugal force is first borne by the steel sleeve 23. The temperature coefficient of the carbon fiber sleeve 24 is small, and the carbon fiber sleeve 24 Assembly is possible with a small amount of interference. The steel sleeve 23 has a large temperature coefficient and is easy to be assembled by the principle of thermal expansion and contraction. However, the rotor of the second comparative example uses sleeves made of two materials, which increases material types and material costs; the eddy current loss generated by the steel sleeve 23 is large, which will reduce the motor efficiency; the two sleeves 120 occupy the air gap. Increased size reduces electromagnetic performance. The deformation mode of the second comparative example rotor is investigated, and the rotor is replaced with a built-in permanent magnet motor structure. Due to the existence of the magnetic bridge, it is difficult to solve the problem of insufficient magnetic bridge strength of the built-in permanent magnet motor at high speed.

Compared with the rotor of the second comparative example, two kinds of sleeves are used. Referring to FIGS. 2 to 4 , the rotor core 100 of the present application can use only one sleeve 120, and there are fewer types of materials and lower material costs; A single sleeve 120 is disposed on the outer surface of the main body 110, so that the size of the air gap occupied by the sleeve 120 is small, which is beneficial to improve the electromagnetic performance. Compared with the deformation mode of the rotor of the second comparative example, the rotor core 100 of the present application adds a sleeve 120 to the rotor body 110 to strengthen the mechanical strength of the rotor body 110 and realize the high-speed operation of the rotor without considering the magnetic bridge at the high-speed rotor. There is a risk that the magnetic bridge is prone to breakage.

FIG. 7 is a schematic structural diagram of a rotor as a third comparative example.

In the rotor of the third comparative example, referring to FIG. 7 , the rotor includes an iron core base 31 and a plurality of iron core accessories 32 distributed along the circumference of the iron core base 31. The iron core base 31 is composed of non-oriented silicon steel laminations, The iron core attachments 32 are composed of oriented silicon steel laminations. Both ends of each iron core attachment 32 are clamped in the outer peripheral slot 31a of the iron core base 31 , and permanent magnets are respectively provided between the iron core base 31 and each iron core attachment 32 . 33. This solution can reduce rotor flux leakage and improve the electromagnetic performance of the motor. However, the rotor of the third comparative example is not reinforced with a sleeve, which is not suitable for high-speed work scenarios. The clamping method between the iron core base body 31 and the iron core attachment 32 is relatively weak, and the applicable maximum rotational speed is low.

Compared to the rotor of the third comparative example, the iron core base 31 and the iron core attachment 32 adopt snap-fit assembly. Referring to FIG. 2 to FIG. 4 , the rotor iron core 100 of the present application adopts the sleeve 120 to strengthen the mechanical strength of the rotor. In high-speed working scenarios, there is no need to consider the risk of the magnetic bridge being easily broken when the rotor rotates at high speed.

FIG. 8 is a schematic structural diagram of a rotor as a fourth comparative example.

In the rotor of the fourth comparative example, referring to FIG. 8 , the rotor includes a rotating shaft 41 and a plurality of iron core accessories 42 distributed along the circumference of the rotating shaft 41 . The rotating shaft 41 has a plurality of sawtooth structures 41 a distributed along the circumference. The sawtooth structure The 41a is clamped in the slot 42a of the iron core attachment 42 so that the iron core attachment 42 is assembled on the outer circumference of the rotating shaft 41, and the sawtooth structure 41a can disperse the stress caused by the high-speed rotation. A permanent magnet 43 is installed between two adjacent iron core accessories 42 to form a spoke type permanent magnet motor. However, the rotor of the fourth comparative example adopts a tangential excitation method, which requires a larger size of the rotor, a larger amount of permanent magnets 43, and a higher cost. The sawtooth structure 41a is used for the connection between the rotating shaft 41 and the iron core attachment 42, and the acceptable stress is low. The centrifugal force of the fourth comparative example is greater than that of the third comparative example, but not as good as the conventional built-in permanent magnet without sleeve. The maximum rotational speed that the magneto can withstand.

Compared with the rotor of the fourth comparative example, which adopts the tangential excitation method, referring to FIGS. 2 to 4 , the rotor using the rotor core 100 of the present application is respectively formed with a first rotor between the core base 111 and each core attachment 112 . For the rotor slot 113, when the permanent magnet 200 is arranged in the first rotor slot 113, the permanent magnet 200 may adopt various built-in forms, such as a straight line, a single V, a double V, a V+one, and the like. With the same electromagnetic performance, the required rotor size is smaller, the amount of the permanent magnet 200 is smaller, and the cost is lower. The rotor core 100 of the present application is sheathed outside the rotor body 110 through the sleeve 120 , which can improve the mechanical strength of the rotor body 110 , so that the rotor can withstand higher rotational speeds.

In some embodiments, referring to FIGS. 2 to 4 , the iron core base 111 and the plurality of iron core accessories 112 in the rotor body 110 are separate structures, and the rotor body 110 is not provided with a magnetic bridge, which is not a conventional built-in permanent magnet. The motor uses an integral rotor core punch. The iron core base 111 and the plurality of iron core accessories 112 can be fixed together by the sleeve 120 to improve the overall structural strength and enable the rotor to withstand higher rotational speeds.

(a), (b), and (c) in FIG. 9 are respectively schematic partial structural diagrams of rotors provided by different embodiments of the present application when magnetic bridges are provided.

In some embodiments, referring to (a), (b), and (c) of FIG. 9 , the first rotor slot 113 is provided with a magnetic bridge 114 , and the magnetic bridge 114 is used to connect the iron core base 111 and the iron core attachment 112 , the thickness of the magnetic bridge 114 is less than or equal to 1 mm. The magnetic bridge 114 is divided into an outer magnetic bridge 114 a close to the outer peripheral surface of the rotor, and a middle magnetic bridge 114 b located between two adjacent permanent magnets 200 . In this embodiment, an outer magnetic bridge 114a or an intermediate magnetic bridge 114b may be provided, and two types of magnetic bridges 114 may also be provided. Compared with the magnetic bridge of the conventional rotor core, the thickness of the magnetic bridge 114 in this embodiment is extremely small, and is only used to connect the core base 111 and the core accessories 112 when the rotor body 110 is processed, so that the rotor body can be connected to the rotor body after stamping. 110 The pick-and-place and assembly operations of the workpiece, the magnetic bridge 114 is not a structure to fix the rotor core 100 and bear the stress when the rotor rotates. When the rotor of this embodiment rotates, the magnetic bridge 114 may be broken. Due to the structure of the sleeve 120 outside the rotor, the overall strength of the rotor will not be affected.

In a conventional built-in permanent magnet motor, the thickness of the magnetic bridge of the rotor is more than 1 mm, and the magnetic bridge should be thickened as the outer diameter of the rotor increases or the rotational speed increases. In the scenario where the rotor speed is above 16000rpm, considering the precision of the mold and the minimum size of the silicon steel sheet that can be processed, the thickness of the magnetic bridge 114 in this embodiment is less than or equal to 1mm. The thickness of the magnetic bridge 114 in this embodiment has nothing to do with the outer diameter of the rotor and the maximum rotational speed of the rotor, and the thickness of the magnetic bridge 114 is approximately set to be twice the thickness of the silicon steel sheet. For example, a 0.3mm silicon steel sheet is used, and the thickness of the magnetic bridge 114 can be set to 0.6mm.

10 is a perspective assembly view of a rotor provided by another embodiment of the application; FIG. 11 is an exploded perspective view of the rotor in FIG. 10 ; FIG. 12 is a cross-sectional view along line B-B of FIG. 10 ; FIG. 13 is another embodiment of the application 3D assembly drawing of the rotor provided.

When disposing the rotor body 110 , referring to FIGS. 10 to 12 , the rotor body 110 is in the shape of a sheet, the number of the rotor body 110 is multiple, the plurality of rotor bodies 110 are arranged in layers, and the iron core accessories 112 in different rotor bodies 110 are arranged in layers. . Multiple stacked rotor bodies 110 are easily formed and assembled. When assembling the rotors, each rotor body 110 may be sleeved with a sleeve 120 , or a plurality of rotor bodies 110 may share a sleeve 120 .

There are different implementations in assembling the rotor body 110 . The first way of assembling is: referring to FIG. 10 to FIG. 12 , a plurality of iron core accessories 112 arranged in layers are connected by fasteners 130 . Referring to FIG. 2 , the fasteners 130 pass through different rotor bodies 110 at the same position. The positioning holes 1121 of the plurality of iron core attachments 112 . The fastener 130 may include a long bolt 131 and a nut 132. The long bolt 131 is passed through the positioning holes 1121 of the plurality of iron core accessories 112, and the nut 132 is used to screw the end of the long bolt 131 to the same axial direction. The iron core accessories 112 are fixed together, the assembly method is easy to operate, the connection is reliable, and the strength of the rotor can be improved. When assembling the rotor, the positioning holes 1121 of the iron core attachment 112 can be used for positioning the sheet iron core attachment 112 during installation. Both ends of the stacked rotor bodies 110 can be provided with end plates 400 . The end plates 400 are provided with holes 401 corresponding to the positioning holes 1121 . During assembly, the fasteners 130 pass through the holes 401 of the end plates 400 and a plurality of irons. After the positioning holes 1121 of the core attachments 112 are located, the two end plates 400 and the plurality of core attachments 112 are fixed together.

The second assembly implementation method is: referring to FIG. 13 , the stacked iron core accessories 112 are connected by injection molded parts (not shown in the figure). Referring to FIG. The first rotor slot 113 of the core attachment 112 . During assembly, the plurality of rotor bodies 110 are assembled, and the partial regions of the first rotor slots 113 of the plurality of laminated iron core accessories 112 are filled with thermal plastic, and after the temperature is lowered, an injection molded part is formed to reliably connect the plurality of iron core accessories 112 together. The positioning holes 1121 of the iron core attachment 112 are used for positioning the sheet iron core attachment 112 during installation. Both ends of the stacked rotor bodies 110 may be provided with end plates 400 , and the end plates 400 do not need to be provided with holes corresponding to the positioning holes.

The third way of assembling is: the stacked iron core accessories 112 are connected by buckles (not shown in the figure), and the buckles are fastened to the buckles of the plurality of iron core accessories 112 at the same position on different rotor bodies 110 slot (not shown). The outer edge of the iron core attachment 112 is provided with a buckle groove. The plurality of iron core accessories 112 can be fixed together by arranging the buckle pieces in the buckle grooves of the aligned plurality of iron core accessories 112 .

There are different implementations when setting the rotor slots. The first implementation of the rotor slot is inline shape: referring to FIGS. 2 and 3 , the first rotor slot 113 is inline shape, and the center extension lines of all the first rotor slots 113 can form a convex polygon. The middle position of each first rotor slot 113 is used to install the permanent magnet 200 , and magnetic isolation slots 1131 are respectively formed at both ends of the first rotor slot 113 (ie, positions close to the outer peripheral surface of the rotor body 110 ). The center extension line of the first rotor slot 113 refers to the center extension line of the region of the first rotor slot 113 for installing the permanent magnet 200 . Exemplarily, the rotor body 110 in FIG. 2 has six first rotor slots 113 , and the central extension lines of the regions where the six first rotor slots 113 are used for installing the permanent magnets 200 are enclosed in a hexagon.

The second implementation manner of the rotor slot is a single V shape: referring to FIG. 4 , the first rotor slot 113 is V-shaped, and the concave side of the first rotor slot 113 is disposed away from the center of the rotor body 110 . The first rotor slot 113 includes two sections of first sub-slots arranged in a V shape, and the middle position of each first sub-slot is used to install the permanent magnet 200 . Magnetic isolation slots 1131 are respectively formed at positions close to the slots.

FIG. 14 is a schematic structural diagram of a rotor provided by another embodiment of the application; FIG. 15 is an exploded schematic diagram of the rotor of FIG. 14 .

The third type of rotor slot implementation is V+ type: refer to Figures 14 and 15, the first rotor slot 113 is V-shaped, and the concave side of the first rotor slot 113 is set away from the center of the rotor body 110; the iron core attachment The 112 has second rotor slots 1122 in a straight line shape, and the central extension lines of all the second rotor slots 1122 can enclose a convex polygon. This method is based on the implementation of the second rotor slot, adding a second rotor slot 1122 in a straight line on the iron core attachment 112, the first rotor slot 113 is used as an inner layer slot and the second rotor slot 1122 is used as a Outer slot. The middle position of the second rotor slot 1122 is used for installing the permanent magnet 200a, and magnetic isolation slots 1123 are formed at both ends of the second rotor slot 1122, respectively. The permanent magnets 200a in the first rotor slot 113 are larger than the permanent magnets 200b in the second rotor slot 1122 in cross-sectional area.

FIG. 16 is a schematic structural diagram of a rotor provided by another embodiment of the present application.

The fourth rotor slot implementation is double V-shape: referring to FIG. 16 , the first rotor slot 113 is V-shaped, and the concave side of the first rotor slot 113 is arranged away from the center of the rotor body 110 ; the iron core attachment 112 has a V-shape. The V-shaped second rotor slot 1122 is provided with the concave side of the second rotor slot 1122 facing away from the center of the rotor body 110 . This method is based on the implementation of the second rotor slot, and a V-shaped second rotor slot 1122 is added to the iron core attachment 112, and the second rotor slot 1122 includes two V-shaped arrangement of the second rotor slot 1122. The sub-slots, the first rotor slot 113 serves as the inner slot and the second rotor slot 1122 serves as the outer slot. The middle position of each second sub-slot is used to install the permanent magnet 200b, and magnetic isolation slots are respectively formed at both ends of the second rotor slot 1122 and at the adjacent positions of the two second sub-slots. The permanent magnets 200a in the first rotor slot 113 are larger than the permanent magnets 200b in the second rotor slot 1122 in cross-sectional area.

The above four rotor slot implementation methods are suitable for the rotor structure of the built-in permanent magnet motor. The permanent magnets 200 are installed in the first rotor slots 113, and a magnetic isolation slot 1131 is formed in part of the first rotor slot 113 to reduce magnetic flux leakage. A predetermined magnetic circuit is formed on the iron core 100 . After installing the permanent magnets 200 in the rotor core 100 of the above four rotor slot implementations, referring to FIGS. 10 and 12 , the rotating shaft 300 is passed through and fixed to the rotor core 100 to obtain a built-in permanent magnet motor rotor.

The following four rotor slot implementations are suitable for a synchronous reluctance motor or a PM-assisted synchronous reluctance motor topology. Synchronous reluctance motor is an AC motor that follows the principle of minimum reluctance path closure, and generates reluctance torque through the reluctance changes caused by the rotor at different positions to drive the rotor to rotate. The rotor slots in the synchronous reluctance motor are not provided with permanent magnets, and the rotor slots are used as magnetic isolation slots. On the basis of the synchronous reluctance motor, after the permanent magnet is placed in the rotor slot, it is called a permanent magnet assisted synchronous reluctance motor. This type of motor operates on the same working principle as the built-in permanent magnet motor.

(a) to (e) in FIG. 17 are partial structural schematic diagrams of rotors provided by different embodiments of the present application, respectively.

The fifth implementation of the rotor slot is: referring to (a) and (b) in FIG. 17 , the first rotor slot 113 is in a U-shape composed of a plurality of straight segments, and the concave side of the first rotor slot 113 faces away from The center of the rotor body 110 is provided. When the permanent magnet 200 is arranged in the first rotor slot 113 , a permanent magnet 200 may be arranged in the middle straight section, and a magnetic isolation slot 1131 is formed in the part of the first rotor slot 113 where the permanent magnet 200 is not arranged. Alternatively, it is also feasible that the permanent magnets 200 are provided on the straight line segments on both sides respectively, and the permanent magnets 200 are not provided on the middle straight line segment. In addition, the permanent magnets 200 may also be disposed in the first rotor slot 113 in other arrangements and combinations.

The sixth implementation of the rotor slot is: referring to (c) in FIG. 17 , the first rotor slot 113 is in a U-shape composed of a plurality of straight segments, and the concave side of the first rotor slot 113 faces away from the rotor body 110 . Centrally arranged; the iron core attachment 112 has a second rotor slot 1122 , the second rotor slot 1122 is U-shaped composed of a plurality of straight segments, and the concave side of the second rotor slot 1122 is arranged away from the center of the rotor body 110 . This method is based on the fifth rotor slot realization method. One or more second rotor slots 1122 are added to the iron core attachment 112. The first rotor slot 113 is used as an inner layer slot and the second rotor slot 1122 is used as an outer layer slot. layer slot. The way of arranging the permanent magnets 200 in the second rotor slot 1122 refers to the situation of the first rotor slot 113. For example, a permanent magnet 200 is arranged in the middle straight section of the first rotor slot 113, and a permanent magnet is also arranged in the middle straight section of the second rotor slot 1122. 200. When a plurality of second rotor slots 1122 are configured on the same iron core attachment 112, there may be two, three or more second rotor slots 1122, and the plurality of second rotor slots 1122 are arranged in turn in the radial direction of the rotor, and the iron core attachment 112 It may include a plurality of sub-attachments arranged in sequence along the radial direction of the rotor, and adjacent sub-attachments may be connected by magnetic bridges or not provided with magnetic bridges.

The seventh implementation of the rotor slot is: referring to FIG. 17 (d), the first rotor slot 113 is arc-shaped, and the concave side of the first rotor slot 113 is disposed away from the center of the rotor body 110 . When the permanent magnet 200 is arranged in the first rotor slot 113 , a permanent magnet 200 may be arranged in the middle straight section, and a magnetic isolation slot 1131 is formed in the part of the first rotor slot 113 where the permanent magnet 200 is not arranged. Alternatively, it is also feasible to dispose the permanent magnets 200 in the regions on both sides of the first rotor slot 113 respectively, and not dispose the permanent magnets 200 in the middle region of the first rotor slot 113 . In addition, the permanent magnets 200 may also be disposed in the first rotor slot 113 in other arrangements and combinations.

The eighth implementation of the rotor slot is: referring to (e) in FIG. 17 , the first rotor slot 113 is arc-shaped, and the concave side of the first rotor slot 113 is arranged away from the center of the rotor body 110 ; the iron core attachment 112 has The arc-shaped second rotor slot 1122 is provided with the concave side of the second rotor slot 1122 facing away from the center of the rotor body 110 . This method is based on the seventh rotor slot realization method, and one or more second rotor slots 1122 are added to the iron core attachment 112, the first rotor slot 113 is used as an inner layer slot and the second rotor slot 1122 is used as an outer layer slot. layer slot. The way of arranging the permanent magnets 200 in the second rotor slot 1122 refers to the situation of the first rotor slot 113 , for example, a permanent magnet is arranged in the middle area of the first rotor slot 113 , and a permanent magnet is also arranged in the middle area of the second rotor slot 1122 . When a plurality of second rotor slots 1122 are configured on the same iron core attachment 112, there may be two, three or more second rotor slots 1122, and the plurality of second rotor slots 1122 are arranged in turn in the radial direction of the rotor, and the iron core attachment 112 It may include a plurality of sub-attachments arranged in sequence along the radial direction of the rotor, and adjacent sub-attachments may be connected by magnetic bridges or not provided with magnetic bridges.

One of the last four rotor cores is used, and rotor slots (a first rotor slot, a second rotor slot) are arranged on the rotor body. Permanent magnets may not be arranged in the rotor slots, and the rotating shaft is passed through and fixed to the rotor core. , the rotor of the synchronous reluctance motor is obtained, and a predetermined magnetic circuit can be formed on the rotor iron core.

One of the last four rotor cores is used. After setting rotor slots (first rotor slot and second rotor slot) on the rotor body and adding permanent magnets, the rotating shaft is passed through and fixed to the rotor core to obtain permanent magnets. The rotor of the auxiliary synchronous reluctance motor can form a predetermined magnetic circuit on the rotor iron core. Compared with the built-in permanent magnet motors using the first to fourth rotor cores, the permanent magnets used in the permanent magnet-assisted synchronous reluctance motors using the latter four rotor cores can be set smaller in size, The reluctance loop is more pronounced, thereby increasing the rotor reluctance torque component.

When arranging the sleeve 120 , referring to FIGS. 2 and 10 , the sleeve 120 can be a carbon fiber sleeve, a steel sleeve or an alloy steel sleeve, and other high-strength materials can also be used. By covering the rotor body 110 with the sleeve 120, the mechanical strength of the rotor structure is improved, so that the rotor can run reliably at high rotational speeds. Using carbon fiber sleeves is better than metal sleeves, reducing eddy current loss to a certain extent and improving motor efficiency. Exemplarily, the outer diameter of the rotor body 110 is 130 mm, and the radial width of the sleeve 120 is 1 mm. The mechanical strength of the rotor body 110 can be effectively improved by placing the sleeve 120 outside the rotor body 110 .

FIG. 18 is a schematic structural diagram of the rotor provided by another embodiment of the application when the iron core attachment is an oriented silicon steel part.

In some embodiments, referring to FIG. 18 , the core base 111 is a non-oriented silicon steel piece, the core attachment 112 is an oriented silicon steel piece, and the magnetization orientation of the core attachment 112 is from the inner edge 112 a to the outer edge 112 b of the core attachment 112 direction. The inner edge 112a of the iron core attachment 112 refers to the edge close to the rotor center after the iron core attachment 112 is assembled to the rotor body 110, and the outer edge 112b of the iron core attachment 112 is the other side opposite to the inner edge 112a. The magnetism of grain-oriented silicon steel has strong directionality, and the magnetism of grain-oriented silicon steel is set in the direction from the inner edge 112a to the outer edge 112b of the core attachment 112 , that is, the direction from the core attachment 112 to the air gap. After the iron core attachment 112 made of grain-oriented silicon steel is used, the magnetic flux leakage in the area of the iron core attachment 112 is effectively reduced, thereby improving the electromagnetic performance. Under the same alternating electromagnetic field, the losses generated by the core attachment 112 will decrease. Compared with the use of snap-fit assembly between the iron core base 31 and the iron core accessory 32 in the rotor of the third comparative example, the rotor iron core 100 of this embodiment fixes the rotor main body 110 through the sleeve 120 , and has higher mechanical strength to accommodate higher rotor speeds.

In another embodiment, the iron core base body 111 and the iron core attachment 112 are both non-oriented silicon steel parts, which is also feasible.

(a) and (b) in FIG. 19 are respectively schematic structural diagrams of a rotor before and after removing the outer convex portion according to another embodiment of the present application.

In some embodiments, referring to FIGS. 1 and 19( a ), the outer periphery of the iron core base 111 has a plurality of mounting positions 1111 distributed along the circumferential direction of the iron core base 111 , and the plurality of iron core accessories 112 are in one-to-one correspondence The iron core base body 111 forms an outer convex portion 1112 between two adjacent mounting positions 1111 , and the outer convex portion 1112 is used for abutting with the inner wall of the sleeve 120 . When assembling the sleeve 120, the inner wall of the sleeve 120 abuts against the outer edge 112b of each iron core attachment 112 and each outer convex portion 1112 of the iron core base 111, so as to reliably fix the iron core base 111 and each iron core attachment 112 together.

In some embodiments, referring to (b) of FIG. 19 , in order to enable the iron core base 111 to be used with iron core accessories 112 of different sizes, the outer circumference of the iron core base 111 has a circumferential distribution of the iron core base 111 . A plurality of mounting positions 1111, a plurality of iron core accessories 112 are provided in the plurality of mounting positions 1111 in a one-to-one correspondence, the iron core base 111 forms a first surface 1113 between two adjacent mounting positions 1111, the first surface 1113 and the sleeve The inner walls of the barrel 120 are arranged at intervals, and the installation positions 1111 can be adapted to various iron core accessories 112 with different outer diameters. When machining the rotor body 110, a tooling or process is added to flush out the outer convex portion 1112 of the iron core base 111, and a first surface 1113 is formed on the outer periphery of the iron core base 111. The installation position 1111 of the iron core base 111 can be within a certain range It is compatible with iron core accessories 112 with different arc outer diameters, and the outer diameter of the rotor can be adjusted to adapt to motors of different specifications, realize platform design, and reduce production costs.

It is difficult for conventional built-in permanent magnet motors to adjust the outer diameter of the rotor through the above methods. The main reason is that the thickness of the magnetic bridge will become thinner under the secondary punching, thus affecting the strength of the rotor. In this embodiment, the mechanical strength of the rotor structure is met by the sleeve 120 sleeved outside the rotor body 110. The iron core base body 111 and the iron core attachment 112 in the rotor body 110 can adopt a separate structure, and the magnetic bridge structure is optional. The outer convex portion 1112 of the iron core base 111 can be washed away without damaging the permanent magnet 200 .

FIG. 20 is a schematic structural diagram of a rotor provided by another embodiment of the application; FIG. 21 is a structural schematic diagram of the rotor of FIG. 20 when the front and back are stacked.

In some embodiments, referring to FIGS. 20 and 21 , in order to use a sheet-like rotor body 110 to achieve the rotor sloping pole effect, the location of the positioning holes 1121 of the core attachment 112 is around the rotor by the symmetry axis 112c of the core attachment 112 The center of the body 110 is offset by a predetermined angle α, and two adjacent rotor bodies 110 are stacked in opposite directions, so that the positioning holes 1121 of the two iron core accessories 112 arranged on top of each other are arranged in a collinear manner. The included angle between the center line of the positioning hole 1121 and the rotor body 110 and the axis of symmetry 112c of the iron core attachment 112 is the predetermined angle α. By reusing the same sheet-shaped rotor body 110, two adjacent rotor bodies 110 are stacked upside down, and the permanent magnets 200 are respectively arranged in the rotor slots of each rotor body 110, and the two adjacent permanent magnets 200 in the rotor axial direction are not It is completely overlapped but staggered by a certain angle. The staggered angle is twice the above-mentioned predetermined angle α, which can achieve the effect of rotor slanting, reduce the torque fluctuation of the motor, and improve the external noise, vibration and harshness of the motor during operation. Degree (noise, vibration, harshness, NVH) performance. The range of the predetermined angle α may be less than or equal to 10°, which is specifically set as required. Exemplarily, when the positioning hole 1121 is offset by 5° from the axis of symmetry of the iron core attachment 112 , the rotor body 110 can be folded upside down and the same sheet-shaped rotor body 110 can be used to achieve a rotor skew effect of ±5°.

An embodiment of the present application provides a motor, including a stator and the above-mentioned rotor, the stator is sleeved on the outer circumference of a sleeve, and an air gap is formed between the stator and the rotor. The motor may be a built-in permanent magnet motor, a synchronous reluctance motor, or a permanent magnet assisted synchronous reluctance motor. Since the motor adopts the above-mentioned rotor, it also has all the beneficial effects brought by the rotor, which will not be repeated here.

An embodiment of the present application provides a motor drive system, including a controller and the above-mentioned motor, and the controller and the motor are electrically connected. The controller is used to adjust the output torque of the motor to realize the functions of idling, acceleration and energy recovery of the motor. Since the motor drive system adopts the above-mentioned motor, it also has all the beneficial effects brought by the motor, which will not be repeated here.

Embodiments of the present application provide an electric vehicle, including the above-mentioned motor drive system. The electric vehicle may be an electric vehicle, a subway train, a high-speed EMU, and the like. The electric vehicle further includes a frame, and the motor drive system can be arranged on the frame. Since the electric vehicle adopts the above-mentioned motor drive system, it also has all the beneficial effects brought by the motor drive system, which will not be repeated here.

Finally, it should be noted that: the above are only specific embodiments of the present application, but the protection scope of the present application is not limited to this, and any changes or replacements within the technical scope disclosed in the present application should be covered by the present application. within the scope of protection of the application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims (15)

1. A rotor core, comprising: a rotor body and a sleeve;

the rotor body comprises an iron core base body and a plurality of iron core accessories, the iron core base body is used for being connected with the rotating shaft, and the plurality of iron core accessories are distributed along the circumferential direction of the iron core base body; first rotor slots are respectively formed between the iron core base body and each iron core accessory, and at least one part of each first rotor slot is provided with a magnetic isolation slot for reducing magnetic leakage;

the sleeve is sleeved on the outer edges of the iron core accessories.

2. The rotor core according to claim 1, wherein the core base and the plurality of core attachments are of a split construction;

or, a magnetic bridge is arranged in the first rotor groove and used for connecting the iron core base body and the iron core accessory, and the thickness of the magnetic bridge is smaller than or equal to 1 mm.

3. The rotor core according to claim 1 or 2, wherein the rotor body is in a sheet shape, the number of the rotor bodies is plural, the plural rotor bodies are stacked, and the core attachments in different rotor bodies are stacked.

4. The rotor core according to claim 3, wherein the plurality of core attachments arranged in a stack are connected by a fastener passing through positioning holes of the plurality of core attachments at the same position on different rotor bodies;

or, the plurality of iron core accessories which are arranged in a stacked mode are connected through injection molding parts, and the injection molding parts are filled in the first rotor grooves of the plurality of iron core accessories at the same position on different rotor bodies;

or, a plurality of iron core accessories which are arranged in a stacked mode are connected through buckle pieces, and the buckle pieces are buckled in the buckling grooves of the iron core accessories at the same position on the rotor body.

5. The rotor core according to claim 3 or 4, wherein the position of the positioning hole of the core attachment is determined by offsetting a predetermined angle around the center of the rotor body by a symmetry axis of the core attachment, and two adjacent rotor bodies are stacked in a forward and backward direction so that the positioning holes of two core attachments disposed in a stacked state are disposed in a line.

6. The rotor core according to any one of claims 1 to 5, wherein the first rotor slots are in a straight shape, and central extension lines of all the first rotor slots can enclose a convex polygon;

or the first rotor groove is V-shaped, and the concave side of the first rotor groove is arranged back to the center of the rotor body;

or the first rotor groove is V-shaped, and the concave side of the first rotor groove is arranged back to the center of the rotor body; the iron core accessory is provided with second rotor slots in a straight shape, and the central extension lines of all the second rotor slots can enclose a convex polygon;

or the first rotor groove is V-shaped, and the concave side of the first rotor groove is arranged back to the center of the rotor body; the iron core accessory is provided with a V-shaped second rotor groove, and the concave side of the second rotor groove is back to the center of the rotor body.

7. The rotor core according to any one of claims 1 to 5, wherein the first rotor slot is U-shaped consisting of a plurality of straight segments, and a concave side of the first rotor slot is disposed facing away from a center of the rotor body;

or the first rotor groove is in a U shape formed by a plurality of straight line segments, and the concave side of the first rotor groove is back to the center of the rotor body; the iron core accessory is provided with a second rotor groove, the second rotor groove is in a U shape formed by a plurality of straight line segments, and the concave side of the second rotor groove is back to the center of the rotor body;

or the first rotor groove is arc-shaped, and the concave side of the first rotor groove is arranged back to the center of the rotor body;

or the first rotor groove is arc-shaped, and the concave side of the first rotor groove is arranged back to the center of the rotor body; the iron core accessory is provided with an arc-shaped second rotor groove, and the concave side of the second rotor groove is back to the center of the rotor body.

8. The rotor core according to any one of claims 1 to 7, wherein the sleeve is a carbon fiber sleeve, a steel sleeve, or an alloy steel sleeve.

9. The rotor core according to any one of claims 1 to 8, wherein the core base and the core attachment are both non-oriented silicon steel pieces;

or the iron core base body is a non-oriented silicon steel piece, the iron core accessories are oriented silicon steel pieces, and the magnetization orientation of the iron core accessories is from the inner edge of the iron core accessories to the outer edge.

10. The rotor core according to any one of claims 1 to 9, wherein the outer periphery of the core base has a plurality of mounting locations distributed along a circumferential direction of the core base, and a plurality of the core attachments are provided in the plurality of mounting locations in a one-to-one correspondence;

the iron core base body forms an outer convex part between two adjacent mounting positions, and the outer convex part is used for being abutted against the inner wall of the sleeve; or the iron core base body is arranged between two adjacent mounting positions to form a first surface, the first surface and the inner wall of the sleeve are arranged at intervals, and the mounting positions can be matched with the iron core accessories with different outer diameters.

11. A rotor comprising a rotor core according to any one of claims 1 to 10, a rotating shaft passing through and fixed to the rotor core, and permanent magnets mounted in the rotor core.

12. A rotor comprising a rotor core according to claim 7 and a rotating shaft passing through and fixed to the rotor core.

13. An electrical machine comprising a stator and a rotor according to claim 11 or 12, the stator being disposed around the outer periphery of the sleeve, and an air gap being formed between the stator and the rotor.

14. A motor drive system comprising a controller and a motor as claimed in claim 13, the controller and the motor being electrically connected.

15. An electric vehicle comprising the motor drive system of claim 14.

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