High-torque-density end-cover-free outer rotor magnetic moment double-adjustment hybrid excitation motor and operation control method thereof

Abstract

The invention provides a high-torque-density end-cover-free outer rotor magnetic moment double-adjustment hybrid excitation motor. The high-torque-density end-cover-free outer rotor magnetic moment double-adjustment hybrid excitation motor comprises an outer rotor, a rotating axial magnetic conduction bridge, a static axial three-phase excitation winding, a stator iron core, a disc type stator and a magnetic isolation bridge. A permanent magnet is embedded in the outer rotor iron core, an axial magnetic bridge is composed of a plurality of fan-shaped magnetic blocks, one end of the axial magnetic bridge is fixed on the bearing, and the other end of the axial magnetic bridge is fixed at the end of the outer rotor; the stator iron core is placed in the outer rotor, the disc-type stator is used for placing a three-phase excitation winding, the radius of the disc-type stator is slightly smaller than the radius of an inner ring of the stator iron core, and the disc-type stator is fixed in the stator iron core and does not change along with rotation of the magnetic bridge. On the basis that an end cover is not used, the problem that a traditional motor is difficult in magnetic adjustment is solved by utilizing the mutual coupling effect among a motor stator end winding magnetic field, permanent magnet leakage flux and a magnetic field generated by an exciting winding, stable output of torque during flux weakening control is achieved, and the flux weakening control efficiency is improved. The motor has the advantages of high torque density, high efficiency, compact structure, high reliability and the like.

Description

Technical Field

[0001] The present invention relates to an end - coverless outer - rotor magnetic - moment dual - regulation hybrid - excitation motor with high torque density and its operation control method, belonging to the technical field of electric machines. Background Art

[0002] With the development of technology, the requirements for the performance and volume of electric machines are getting higher and higher. As the core device for energy conversion, electric machines are increasingly widely used in industries, transportation, aerospace and other fields. Especially in high - torque application scenarios, the high torque density, high efficiency and good operating performance of electric machines have become key technical indicators. Permanent - magnet motors have received extensive attention due to their characteristics such as compact structure, high torque density and excellent efficiency. However, when traditional permanent - magnet motors face different operating conditions, there are difficulties in magnetic - field regulation. Especially during the process of accelerating from low speed to high speed, field - weakening control will cause a significant decrease in the output torque, which limits their popularization in high - performance applications.

[0003] In recent years, hybrid - excitation motors have gradually received attention as an effective solution. Hybrid - excitation motors combine the high power density and high - efficiency characteristics of permanent - magnet motors, and achieve magnetic - field regulation by introducing an excitation winding, broadening the speed - regulation range of the motor. However, the structure of hybrid - excitation motors is complex, magnetic - field decoupling is difficult, and the optimization design is also difficult. Although domestic and foreign scholars have conducted a large amount of research on the optimization of motor structure and control strategies, the existing technologies are still difficult to maintain high torque output of the motor in the field - weakening state.

[0004] Therefore, how to achieve efficient magnetic - field regulation while maintaining the high torque density of the motor and solve the problem of torque decline during field - weakening has become an urgent problem to be solved in the current technical field of electric machines. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art, and provide an end - coverless outer - rotor magnetic - moment dual - regulation hybrid - excitation motor with high torque density and its operation control method. Through the innovative design of the axial magnetic - conduction bridge, disc - type stator and magnetic - isolation bridge, the motor realizes efficient magnetic - field regulation and solves the problem of difficult magnetic - field regulation of traditional permanent - magnet motors. At the same time, by optimizing the interaction between the excitation magnetic field and the permanent - magnet magnetic field, a relatively high output torque can still be maintained during field - weakening control, significantly improving the operating performance of the motor. In addition, the motor adopts a compact design, has the characteristics of high torque density and high efficiency, and is suitable for high - torque application scenarios.

[0006] The technical solution adopted by the present invention to solve the technical problem is as follows: An end - coverless outer - rotor magnetic - moment dual - regulation hybrid - excitation motor with high torque density, comprising an outer rotor, a rotating axial magnetic - conduction bridge, a stationary axial three - phase excitation winding, a stator core, a disc - type stator and a magnetic - isolation bridge; The described outer rotor has tangentially magnetized permanent magnets embedded in its iron core, forming an N - pole region and an S - pole region; The described axial magnetic conduction bridge is composed of several sector - shaped magnetic conduction blocks. One end of it is evenly fixed on the bearing, and the other end is evenly fixed on the N - pole region and S - pole region at the end of the outer rotor, connecting to the outer rotor without air gap and rotating with it, playing a core supporting role of the end cover; The described stator core is placed inside the outer rotor, forming the main structure of the outer - rotor motor; The described disc - type stator is used to place the three - phase excitation winding. Its radius is slightly smaller than the inner - ring radius of the stator core and is fixed inside the stator core. Its teeth face the magnetic conduction bridge and there is an air gap between them, and its position does not change with the rotation of the magnetic conduction bridge; The described magnetic isolation bridge is made of non - magnetic conductive materials and is placed in the air gap between the stator core and the disc - type stator, used to fix the stator core and reduce the influence of the excitation magnetic field on the armature current.

[0007] Preferably, the number Zo of the magnetic conduction blocks and the number of poles P of the motor satisfy the relationship Zo = P, which is used to optimize the magnetic circuit distribution; each magnetic conduction block fills the N - pole region or S - pole region as much as possible and extends to the bearing in a sector shape, so as to have a larger magnetic - field - adjusting ability.

[0008] Preferably, the height of the stator core is slightly smaller than the height of the outer rotor. The teeth of the disc - type stator are exposed outside the stator core, and the yoke is fixed inside the stator core by the magnetic isolation bridge.

[0009] Preferably, both the stator core and the disc - type stator adopt three - phase windings, and the speed and torque of the motor are driven and adjusted by applying three - phase alternating current; the three - phase excitation winding adopts a concentrated winding and is placed in the disc - type stator to improve the power density and operating efficiency of the motor.

[0010] Preferably, the ratio of the axial length to the radial length of the motor is less than 1 to achieve the compactness and high torque density of the motor; the tangential magnetization method of the permanent magnet makes the N - pole region and S - pole region of the outer rotor evenly distributed, so as to improve the torque density of the motor.

[0011] Preferably, a heat - dissipation structure is arranged on the outer surface of the outer rotor to improve the heat - dissipation efficiency of the motor.

[0012] Preferably, the magnetic isolation bridge adopts magnetic isolation materials such as cobalt - nickel - aluminum, etc.; the magnetic conduction blocks adopt magnetic - conductive materials.

[0013] The operating control method of the high - torque - density end - cover - less outer - rotor magnetic - moment dual - regulation hybrid - excitation motor: A. When the motor is running, the internal winding of the stator core generates a rotating magnetic field, which interacts with the magnetic field of the permanent magnet to generate a torque that causes the outer rotor to rotate. At the same time, a rotating magnetic field is generated at the end of the stator winding, and its direction is the same as that of the magnetic field of the internal winding of the stator core. The axial leakage magnetic flux of the permanent magnet passes through the magnetic conduction bridge, generating a magnetic field with the same direction on the magnetic conduction bridge. This magnetic field interacts with the magnetic field generated at the stator end to generate an additional torque in the same direction as the main torque of the motor, thereby enhancing the electromagnetic torque of the motor. B. When three-phase alternating current is applied to the three-phase excitation windings inside the disc-shaped stator, an excitation magnetic field is generated on the disc-shaped stator. This magnetic field forms an excitation magnetic field on the magnetic conduction bridge, and the magnitude and direction of this excitation magnetic field change with the amplitude and phase of the excitation current. When the torque direction generated by the armature magnetic field on the rotor magnetic conduction block is the same as that of the excitation magnetic field, the excitation current is in the torque-increasing state; when the torque direction generated by the armature magnetic field on the rotor magnetic conduction block is opposite to that of the excitation magnetic field, the excitation current is in the braking state. C. The magnetic field of the magnetic conduction bridge is composed of the leakage magnetic flux of the permanent magnet and the excitation magnetic field generated by the disc-shaped stator. When the excitation magnetic field is in the same direction as the leakage magnetic field of the permanent magnet, it promotes the increase of the leakage magnetic flux of the permanent magnet, resulting in a decrease in the main magnetic flux of the motor; when the excitation magnetic field is in the opposite direction to the leakage magnetic field of the permanent magnet, it inhibits the leakage magnetic flux of the permanent magnet, resulting in an increase in the main magnetic flux of the motor. When the excitation magnetic field is greater than the leakage magnetic flux of the permanent magnet, it directly increases the main magnetic flux of the motor. By adjusting the magnitude and direction of the excitation magnetic field, the magnetic flux regulation of the motor is achieved.

[0014] The working principle of the present invention is as follows: When the motor is running, the internal winding of the inner stator core generates a rotating magnetic field that interacts with the magnetic field of the permanent magnet to generate a torque that causes the outer rotor to rotate. At the same time, a rotating magnetic field is also generated at the end of the stator winding, and this magnetic field has the same direction as the magnetic field generated by the internal winding of the stator core. In addition, the axial leakage magnetic flux of the permanent magnet passes through the magnetic conduction bridge of the motor, generating a magnetic field with the same direction on the magnetic conduction bridge. This magnetic field interacts with the magnetic field generated at the stator end to generate a torque, and this torque is in the same direction as the main torque of the motor, thereby enhancing the electromagnetic torque of the motor.

[0015] When an exciting current is applied to the three-phase exciting windings of the disc stator (the current applied to the exciting windings is three-phase alternating current), a magnetic field will be generated on the disc stator, thereby forming an exciting magnetic field on the magnetic conduction bridge, and the magnitude and direction of this exciting magnetic field can change with the amplitude and phase of the exciting current. When each magnetic conduction block on the magnetic conduction bridge is the same as the corresponding rotor pole region, as the rotor rotates, the pole regions of the rotor get closer. At this time, the same magnetic poles between the two repel each other. When the pole region of the rotor moves away from the magnetic conduction block, the direction of the exciting magnetic field is adjusted to make its polarity opposite. At this time, the two attract each other, playing a role in weakening the electromagnetic torque; when each magnetic conduction block on the magnetic conduction bridge is opposite to the corresponding rotor pole region, as the rotor rotates, the pole regions of the rotor get closer. At this time, the opposite magnetic poles between the two attract each other. When the pole region of the rotor moves away from the magnetic conduction block, the direction of the exciting magnetic field is adjusted to make its polarity opposite. At this time, the two repel each other, playing a role in enhancing the electromagnetic torque.

[0016] The magnetic field of the magnetic conduction bridge is composed of the leakage magnetic field of the permanent magnet and the exciting magnetic field generated by the three-phase exciting current on the disc stator. When the exciting magnetic field is in the same direction as the leakage magnetic field of the permanent magnet, it promotes the leakage magnetic field of the permanent magnet, increasing the leakage magnetic field and reducing the main magnetic flux of the motor; when the exciting magnetic field is in the opposite direction to the magnetic field of the permanent magnet, it will inhibit the leakage magnetic field of the permanent magnet, increasing the main magnetic flux of the motor. And when the exciting magnetic field is greater than the leakage magnetic field of the permanent magnet, it will directly increase the main magnetic flux of the motor. Therefore, adjusting the magnitude and direction of the exciting magnetic field can play a role in magnetic field regulation of the motor.

[0017] During the rotation of the rotor, when the magnetic field generated by the disc stator leads the magnetic field generated by the permanent magnet on the outer rotor, the exciting current is in a driving role at this time; when the magnetic field generated by the disc stator lags the magnetic field generated by the permanent magnet on the outer rotor, the exciting current is in a braking role at this time. By adjusting the phase of the exciting current, the torque regulation of the outer rotor magneto-moment double-regulated hybrid excitation motor can be achieved.

[0018] The present invention can be used for a 16-pole motor and can also be used as a motor with other pole numbers.

[0019] The end-capless outer rotor magneto-moment double-regulated hybrid excitation motor proposed by the present invention, through innovative structural design and control methods, solves many problems of traditional permanent magnet outer rotor motors and hybrid excitation motors in terms of magnetic field regulation, torque output, and structural design, and has the following positive and beneficial effects: 1. High-efficiency magnetic field regulation ability: ① Through the collaborative design of the axial magnetic conduction bridge, disc stator, and magnetic isolation bridge, the present invention realizes the efficient coupling of the exciting magnetic field and the permanent magnet magnetic field, significantly improving the accuracy and range of magnetic field regulation.

[0020] ②During the process of the motor accelerating from low speed to high speed, by adjusting the amplitude and phase of the excitation current, the present invention can achieve precise field weakening control, avoid the problem of torque drop in traditional motors during field weakening, and ensure that the motor can maintain excellent operating performance under different working conditions.

[0021] 2. High torque density and high efficiency: ①The present invention adopts an outer rotor structure and a compact design, optimizing the space utilization rate of the motor and significantly improving the torque density of the motor.

[0022] ②Through the synergistic effect of the permanent magnet and the excitation magnetic field, the present invention reduces the magnetic circuit loss and improves the overall efficiency of the motor, making it suitable for applications with large torque and high performance.

[0023] 3. Torque holding ability during field weakening control: By optimizing the interaction between the excitation magnetic field and the permanent magnet magnetic field, the present invention can still maintain a high output torque during field weakening control, solve the problem of significant torque drop in traditional hybrid excitation motors during field weakening, and improve the dynamic performance and operating stability of the motor.

[0024] 4. Compact structure and high reliability: ①The present invention adopts an end - cover - less design and an axial magnetic conduction bridge structure, simplifying the mechanical structure of the motor, reducing the limitation of the end cover on the motor performance, and at the same time improving the mechanical strength and reliability of the motor.

[0025] ②The magnetic isolation bridge of the present invention uses high - strength non - magnetic conductive materials, which not only plays a role in fixing the disc - type stator, but also can effectively reduce the interference of the axial magnetic flux on the armature current, further improving the operating stability of the motor.

[0026] 5. Excellent heat dissipation performance: The outer surface of the outer rotor of the present invention is provided with a heat dissipation structure, which can effectively improve the heat dissipation efficiency of the motor, avoid performance degradation caused by excessive temperature rise, and extend the service life of the motor.

[0027] 6. Wide application prospects: The present invention is applicable to occasions that require high torque density, high efficiency, and a wide speed regulation range, such as electric vehicles, wind power generation, industrial drive and other fields, and has broad market application prospects.

[0028] In summary, through innovative structural design and control methods, the present invention not only solves the problem of difficult field weakening in traditional motors, but also realizes stable torque output during field weakening control. On the basis of not using an end cover, the present invention utilizes the mutual coupling effect among the magnetic field of the stator end winding of the motor, the leakage magnetic field of the permanent magnet, and the magnetic field generated by the exciting winding, thus realizing both magnetic field regulation and torque regulation. It has the advantages of high torque density, high efficiency, compact structure, and high reliability, providing a new technical solution for the development and application of high-performance motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic cross-sectional view of the present invention; Figure 2 is a schematic overall view of the present invention; Figure 3 is a schematic view of the outer rotor and permanent magnet in the present invention; Figure 4 is a schematic view of the stator core in the present invention; Figure 5 is a schematic view of the magnetic conduction block and bearing connection in the present invention; Figure 6 is a schematic view of the disc-shaped stator in the present invention; Figure 7 is a schematic view of the magnetic isolation bridge in the present invention; Figure 8 is a schematic view of the spatial position of the magnetic conduction block and disc-shaped stator in the present invention; Figure 9 is a schematic view of the spatial position of the stator core, disc-shaped stator, and magnetic isolation bridge in the present invention; Figure 10 is a schematic view of the spatial position of the outer rotor, permanent magnet, stator core, disc-shaped stator, and magnetic isolation bridge in the present invention.

[0030] In the figures, 1 - outer rotor, 2 - permanent magnet, 3 - stator core, 4 - magnetic conduction bridge, 5 - bearing, 6 - disc-shaped stator, 7 - magnetic isolation bridge.

[0031] In the present invention, the drawings are only for illustrative purposes and should not be construed as a limitation to this patent. To better illustrate the technical solution of the present invention, some parts of the drawings are omitted, enlarged, or reduced, and do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. Without creative efforts, other corresponding drawings can also be obtained based on these drawings. By reading the detailed description of the non-limiting embodiments with reference to the drawings, other features, objectives, and advantages of the present invention will become more apparent. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] To make the technical means, creative features, achieved objectives and effects of the present invention easily understood, the technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0033] Embodiment: As Figures 1 to 10 shown, this embodiment takes a sixteen-pole motor as an example to describe in detail the technical solution of the present invention.

[0034] A high-torque density end-capless outer-rotor magnetic moment dual-regulation hybrid excitation motor includes an outer rotor 1, a rotating axial magnetic conduction bridge 4, a stationary axial three-phase excitation winding, a stator core 3, a disc-shaped stator 6, and a magnetic isolation bridge 7; The outer rotor 1 has tangentially magnetized permanent magnets 2 embedded in its iron core, forming an N-pole region and an S-pole region; The axial magnetic conduction bridge 4 is composed of a plurality of sector-shaped magnetic conduction blocks. One end of it is uniformly fixed on the bearing 5, and the other end is uniformly fixed on the N-pole region and the S-pole region at the end of the outer rotor. It is connected to the outer rotor without an air gap and rotates with it, playing a core supporting role of the end cap; The stator core 3 is placed inside the outer rotor 1, forming the main structure of the outer-rotor motor; The disc-shaped stator 6 is used to place the three-phase excitation winding. Its radius is slightly smaller than the inner-ring radius of the stator core 3 and is fixed inside the stator core. Its tooth part faces the magnetic conduction bridge and there is an air gap between it and the magnetic conduction bridge, and its position does not change with the rotation of the magnetic conduction bridge; The magnetic isolation bridge 7 is made of a non-magnetic conductive material and is placed in the air gap between the stator core 3 and the disc-shaped stator 6, used to fix the stator core and reduce the influence of the excitation magnetic field on the armature current.

[0035] The number Zo of the magnetic conduction blocks and the number of poles P of the motor satisfy the relationship Zo = P, which is used to optimize the magnetic circuit distribution; each magnetic conduction block fills the N-pole region or the S-pole region as much as possible and extends to the bearing in a sector shape, so as to have a larger magnetic regulation ability.

[0036] The height of the stator core 3 is slightly smaller than the height of the outer rotor 1. The tooth part of the disc-shaped stator 6 is exposed outside the stator core 3, and the yoke part is fixed inside the stator core 3 by the magnetic isolation bridge 7.

[0037] Both the stator core 3 and the disc-shaped stator 6 adopt three-phase windings, and the speed and torque of the motor are driven and adjusted by applying three-phase alternating current; the three-phase excitation winding adopts a concentrated winding and is placed in the disc-shaped stator to improve the power density and operating efficiency of the electrode.

[0038] The ratio of the axial length to the radial length of the motor is less than 1 to achieve the compactness and high torque density of the motor; the tangential magnetization method of the permanent magnet 2 makes the N-pole region and S-pole region of the outer rotor evenly distributed to improve the torque density of the motor.

[0039] A heat dissipation structure is provided on the outer surface of the outer rotor 1 to improve the heat dissipation efficiency of the motor.

[0040] The operation control method of the end-coverless outer-rotor magnetic moment dual-regulation hybrid excitation motor with high torque density: A. When the motor is running, the internal winding of the stator core 3 generates a rotating magnetic field, which interacts with the magnetic field of the permanent magnet 2 to generate a torque to make the outer rotor 1 rotate; at the same time, a rotating magnetic field is generated at the end of the stator winding, and its direction is the same as the magnetic field direction of the internal winding of the stator core. The axial leakage magnetic flux of the permanent magnet 2 passes through the magnetic conduction bridge 4 to generate a magnetic field with the same direction on the magnetic conduction bridge 4. This magnetic field interacts with the magnetic field generated at the end of the stator to generate an additional torque in the same direction as the main torque of the motor, thereby enhancing the electromagnetic torque of the motor. B. When three-phase alternating current is applied to the three-phase excitation winding inside the disc-shaped stator 6, an excitation magnetic field is generated on the disc-shaped stator 6. This magnetic field forms an excitation magnetic field on the magnetic conduction bridge 4, and the magnitude and direction of this excitation magnetic field change with the amplitude and phase of the excitation current. When the torque direction generated by the armature magnetic field on the rotor magnetic conduction block is the same as the torque direction generated by the excitation magnetic field, the excitation current is in the torque-increasing state; when the torque direction generated by the armature magnetic field on the rotor magnetic conduction block is opposite to the torque direction generated by the excitation magnetic field, the excitation current is in the braking state. C. The magnetic field of the magnetic conduction bridge 4 is composed of the leakage magnetic flux of the permanent magnet 2 and the excitation magnetic field generated by the disc-shaped stator 6. When the excitation magnetic field is in the same direction as the leakage magnetic field of the permanent magnet, it promotes the increase of the leakage magnetic flux of the permanent magnet, resulting in a decrease in the main magnetic flux of the motor; when the excitation magnetic field is opposite to the leakage magnetic field of the permanent magnet, it inhibits the leakage magnetic flux of the permanent magnet, resulting in an increase in the main magnetic flux of the motor. When the excitation magnetic field is greater than the leakage magnetic flux of the permanent magnet, it directly increases the main magnetic flux of the motor, and by adjusting the magnitude and direction of the excitation magnetic field, the magnetic flux regulation effect on the motor is achieved.

[0041] The magnetic conduction bridge 4 is made of a magnetic conduction material, and the magnetic isolation bridge 7 is made of a non-magnetic conduction material.

[0042] Both the disc-shaped stator 6 and the stator core 3 adopt three-phase windings, and the speed and torque of the motor are driven and adjusted by applying three-phase alternating current.

[0043] The working principle of the present invention is as follows: When the motor is running, the internal winding of the inner stator core 3 generates a rotating magnetic field that interacts with the magnetic field of the permanent magnet 2, generating a torque that causes the outer rotor 1 to rotate. At the same time, a rotating magnetic field is also generated at the end of the stator winding, and the direction of this magnetic field is the same as that of the magnetic field generated by the internal winding of the stator core 3. In addition, the axial leakage magnetic flux of the permanent magnet 2 passes through the magnetic conduction bridge 4 of the motor, generating a magnetic field with the same direction on the magnetic conduction bridge 4. This magnetic field interacts with the magnetic field generated at the stator end, generating a torque, and this torque is in the same direction as the main torque of the motor, thereby enhancing the electromagnetic torque of the motor.

[0044] When exciting current is applied to the three-phase exciting windings of the disc-shaped stator 6 (the current applied to the exciting windings is three-phase alternating current), a magnetic field will be generated on the disc-shaped stator 6, thereby forming an exciting magnetic field on the magnetic conduction bridge 4, and the magnitude and direction of this exciting magnetic field can change with the amplitude and phase of the exciting current. When each magnetic conduction block on the magnetic conduction bridge 4 is the same as the corresponding outer rotor 1 pole region, as the outer rotor 1 rotates, the pole regions of the outer rotor 1 approach continuously. At this time, the same magnetic poles between the two repel each other. When the pole region of the outer rotor 1 moves away from the magnetic conduction block, the direction of the exciting magnetic field is adjusted to make its polarity opposite. At this time, the two attract each other, playing a role in weakening the electromagnetic torque; when each magnetic conduction block on the magnetic conduction bridge 4 is opposite to the corresponding outer rotor 1 pole region, as the outer rotor 1 rotates, the pole regions of the outer rotor 1 approach continuously. At this time, the opposite magnetic poles between the two attract each other. When the pole region of the outer rotor 1 moves away from the magnetic conduction block, the direction of the exciting magnetic field is adjusted to make its polarity opposite. At this time, the two repel each other, playing a role in enhancing the electromagnetic torque.

[0045] The magnetic field of the magnetic conduction bridge 4 is composed of the leakage magnetic flux of the permanent magnet 2 and the exciting magnetic field generated by the three-phase exciting current on the disc-shaped stator 6. When the exciting magnetic field is in the same direction as the permanent magnet leakage magnetic field, it promotes the leakage magnetic flux of the permanent magnet 2, increasing the leakage magnetic flux and reducing the main magnetic flux of the motor; when the exciting magnetic field is in the opposite direction to the permanent magnet magnetic field, it inhibits the leakage magnetic flux of the permanent magnet 2, increasing the main magnetic flux of the motor. And when the exciting magnetic field is greater than the permanent magnet leakage magnetic flux, it directly increases the main magnetic flux of the motor. Therefore, adjusting the magnitude and direction of the exciting magnetic field can play a role in adjusting the magnetic field of the motor.

[0046] During the rotation of the rotor 1, when the magnetic field generated by the disc-shaped stator 6 leads the magnetic field generated by the permanent magnet 2 on the outer rotor 1, the exciting current is in a driving role at this time; when the magnetic field generated by the disc-shaped stator 6 lags behind the magnetic field generated by the permanent magnet 2 on the outer rotor 1, the exciting current is in a braking role at this time. By adjusting the phase of the exciting current, the torque adjustment of the outer rotor magnetic moment doubly-fed hybrid excitation motor can be realized.

[0047] The present invention can be used for a 16-pole motor and can also be used as a motor with other pole numbers.

[0048] The present invention provides an end - cover - less outer - rotor magnetic - moment dual - adjustment hybrid - excitation motor that can adjust both magnetic flux and torque. By utilizing the interaction and coupling among the magnetic field of the end - winding of the motor, the leakage magnetic flux of the permanent magnet, and the magnetic field of the excitation coil, the purpose of adjusting both magnetic flux and torque is achieved.

[0049] The above - mentioned embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above - mentioned embodiments, those of ordinary skill in the art should understand that: still modifications or equivalent substitutions can be made to the present invention, and any modification or partial substitution without departing from the spirit and scope of the present invention should be covered by the scope of the claims of the present invention.

[0050] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the protected content of the present invention. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. An end - coverless outer - rotor magnetic - moment dual - regulated hybrid - excitation motor with high torque density, characterized in that: It includes an outer rotor, a rotating axial magnetic conduction bridge, a stationary axial three-phase exciting winding, a stator core, a disc-shaped stator and a magnetic isolation bridge; For the said outer rotor, tangentially magnetized permanent magnets are embedded in its iron core to form an N-pole region and an S-pole region; The said axial magnetic conduction bridge consists of several sector-shaped magnetic conduction blocks. One end of it is uniformly fixed on the bearing, and the other end is uniformly fixed on the N-pole region and S-pole region at the end of the outer rotor, connecting with the outer rotor without air gap and rotating with it, playing the core supporting role of the end cover; The said stator core is placed inside the outer rotor to form the main structure of the outer rotor motor; The said disc-shaped stator is used to place the three-phase exciting winding. Its radius is slightly smaller than the inner ring radius of the stator core and is fixed inside the stator core. Its tooth part faces the magnetic conduction bridge and there is an air gap between them, and its position does not change with the rotation of the magnetic conduction bridge; The said magnetic isolation bridge is made of non-magnetic conductive material and is placed in the air gap between the stator core and the disc-shaped stator, used to fix the stator core and reduce the influence of the exciting magnetic field on the armature current.

2. The non-end-cover outer-rotor magnetic moment dual-regulation hybrid excitation motor with high torque density according to claim 1, wherein: The number Zo of the said magnetic conduction blocks and the number of poles P of the motor satisfy the relationship Zo = P, which is used to optimize the magnetic circuit distribution; each magnetic conduction block fills the N-pole region or S-pole region as much as possible and extends to the bearing in a sector shape, so as to have a large magnetic regulation ability.

3. A brushless end - cover outer - rotor magnetic - moment dual - regulation hybrid - excitation motor with high torque density according to claim 1, characterized in that: The height of the said stator core is slightly smaller than the height of the outer rotor. The tooth part of the disc-shaped stator is exposed outside the stator core, and the yoke part is fixed inside the stator core by the magnetic isolation bridge.

4. A frameless outer-rotor magnetically adjustable hybrid-excitation motor with high torque density according to claim 1, characterized in that: Both the said stator core and the disc-shaped stator adopt three-phase windings, and the speed and torque of the motor are driven and adjusted by passing three-phase alternating current; the said three-phase exciting winding adopts a concentrated winding and is placed in the disc-shaped stator to improve the power density and operating efficiency of the electrode.

5. A non-end-cover outer-rotor magnetic moment dual-tuning hybrid excitation motor with high torque density according to claim 1, characterized in that: The ratio of the axial length to the radial length of the said motor is less than 1 to achieve the compactness and high torque density of the motor; the tangential magnetization mode of the permanent magnet makes the N-pole region and S-pole region of the outer rotor evenly distributed to improve the torque density of the motor.

6. A non-end-cover outer-rotor magnetic moment dual-tuning hybrid excitation motor with high torque density according to claim 1, wherein: A heat dissipation structure is arranged on the outer surface of the said outer rotor to improve the heat dissipation efficiency of the motor.

7. The operation control method of the high torque density end-capless outer rotor magnetic moment dual-regulation hybrid excitation motor according to any one of claims 1 to 6, characterized in that: A. When the motor is running, the internal winding of the stator core generates a rotating magnetic field, which interacts with the magnetic field of the permanent magnet to generate a torque to make the outer rotor rotate; at the same time, a rotating magnetic field is generated at the end of the stator winding, and its direction is the same as the magnetic field direction of the internal winding of the stator core; The axial leakage magnetic flux of the permanent magnet passes through the magnetic conduction bridge to generate a magnetic field with the same direction on the magnetic conduction bridge. This magnetic field interacts with the magnetic field generated at the stator end to generate an additional torque in the same direction as the main torque of the motor, thereby enhancing the electromagnetic torque of the motor; B. When three-phase alternating current is passed through the three-phase exciting winding inside the disc-shaped stator, an exciting magnetic field is generated on the disc-shaped stator. This magnetic field forms an exciting magnetic field on the magnetic conduction bridge, and the magnitude and direction of this exciting magnetic field change with the amplitude and phase of the exciting current; When the torque direction generated by the armature magnetic field on the rotor magnetic conduction block is the same as that of the excitation magnetic field, the excitation current is in the torque increasing state; when the torque direction generated by the armature magnetic field on the rotor magnetic conduction block is opposite to that of the excitation magnetic field, the excitation current is in the braking state; C. The magnetic field of the magnetic conduction bridge is composed of the leakage magnetic flux of the permanent magnet and the excitation magnetic field generated by the disk stator. When the excitation magnetic field is in the same direction as the leakage magnetic field of the permanent magnet, it promotes the increase of the leakage magnetic flux of the permanent magnet, resulting in a decrease in the main magnetic flux of the motor; when the excitation magnetic field is in the opposite direction to the leakage magnetic field of the permanent magnet, it suppresses the leakage magnetic flux of the permanent magnet, resulting in an increase in the main magnetic flux of the motor; When the excitation magnetic field is greater than the leakage magnetic flux of the permanent magnet, it directly increases the main magnetic flux of the motor, and realizes the magnetic field regulation of the motor by adjusting the magnitude and direction of the excitation magnetic field.

Images