Hub motor with outer rotor structure

Abstract

The invention discloses a hub motor with an outer rotor structure, belongs to the field of motors, and aims to solve the problems that the roundness of a rotor becomes poor due to poor connection between a hub motor shell and the rotor and the performance of the motor is affected due to the fact that a permanent magnet is easy to fall off. The hub motor comprises an outer rotor, an inner stator and a shell, wherein the outer rotor comprises a permanent magnet, a rotor iron core and a C-shaped connecting piece; p mounting grooves are uniformly distributed in the inner circle surface of the casing along the circumferential direction, and the C-shaped connecting piece assembles the rotor iron core into the casing; the inner stator is arranged in the outer rotor and has a radial gap; p permanent magnet positioning teeth are evenly distributed on the inner circle surface of the rotor core in the circumferential direction, a permanent magnet is embedded between every two adjacent permanent magnet positioning teeth in a mortise and tenon mode, and the upper clamping ends of P C-shaped connecting pieces and P mounting grooves in the inner circle surface of a machine shell are assembled together in a mortise and tenon mode. The lower clamping ends of the P C-shaped connecting pieces and the end portions of the P permanent magnet positioning teeth are assembled in a matched mode, and the P C-shaped connecting pieces and the P permanent magnets are kept on the same roundness.

Description

Technical Field

[0001] The present invention relates to an assembly technology for an outer rotor and a housing of a wheel hub motor, belonging to the field of motors. Background Art

[0002] In order to cope with the increasingly severe global energy crisis and environmental pollution problems, the wheel hub motor technology, as one of the key technologies of new energy vehicles, has gradually become the future development direction of the automotive industry due to its advantages such as high transmission efficiency, compact structure, small volume, high power density, and high torque density. At the same time, due to the relatively thin thickness of the rotor and the housing of the wheel hub motor, the traditional interference installation method and the special working environment make it easy to have problems such as poor connection in the connection and assembly between the relatively thin rotor and the housing of the wheel hub motor, poor roundness of the rotor, easy deformation of the rotor and the housing, easy eccentricity of the rotor, and poor vibration and noise. Summary of the Invention

[0003] Aiming at the problems of poor roundness of the rotor and easy detachment of the permanent magnet caused by the poor connection between the housing and the rotor of the wheel hub motor, which affect the performance of the motor, the present invention provides a wheel hub motor with an outer rotor structure.

[0004] The wheel hub motor with an outer rotor structure according to the present invention includes an outer rotor, an inner stator 5, and a housing 4. The outer rotor includes a permanent magnet 1, a rotor core 2, and a C-shaped connecting member 3. P mounting grooves are evenly distributed along the circumferential direction on the inner circular surface of the housing 4. The C-shaped connecting member 3 assembles the rotor core 2 into the interior of the housing 4. The inner stator 5 is arranged inside the outer rotor, and there is a radial gap between the two.

[0005] P permanent magnet positioning teeth 2-1 are evenly distributed along the circumferential direction on the inner circular surface of the rotor core 2. A permanent magnet 1 is embedded between two adjacent permanent magnet positioning teeth 2-1 in a mortise and tenon manner. The upper clamping ends of the P C-shaped connecting members 3 are respectively assembled with the P mounting grooves on the inner circular surface of the housing 4 in a mortise and tenon manner. The lower clamping ends of the P C-shaped connecting members 3 are respectively fitted and assembled with the end parts of the P permanent magnet positioning teeth 2-1, and the P C-shaped connecting members 3 and the P permanent magnets 1 are kept on the same roundness.

[0006] Preferably, the permanent magnet positioning teeth 2-1 of the rotor core 2 are strip-shaped structures extending axially, and the radial cross-section is two trapezoidal structures with the same bottom. Among them, the top side of the upper trapezoid is connected to the yoke part of the rotor core 2, with a size of A; the bottom side of the upper trapezoid coincides with the bottom side of the lower trapezoid, with a size of B, and the top side of the lower trapezoid is close to the air gap side, with a size of E, satisfying the relationship: A < B, E < B, and the distance from the top side of the lower trapezoid to the air gap side is F.

[0007] Preferably, the permanent magnet 1 is composed of a single permanent magnet block or multiple permanent magnet blocks arranged in parallel. The tangential dimension of the permanent magnet 1 at the rotor yoke side is G, and the tangential dimension of the permanent magnet 1 at the air gap side is H, satisfying the relationship: G > H, and the permanent magnet 1 and the two adjacent permanent magnet positioning teeth 2-1 form a mortise and tenon structure.

[0008] Preferably, the C-shaped connector 3 includes an upper clamping end 3-1, a lower clamping end 3-2 and an intermediate connector 3-3; the upper clamping end 3-1 and the lower clamping end 3-2 are axially extending strip structures, the radial cross section of the upper clamping end 3-1 is a trapezoidal structure, the bottom side of the trapezoidal structure is on the casing side, and the size is I; the top side of the trapezoidal structure is on the rotor core side, and the size is N; satisfying the relationship: I>N; the lower clamping end 3-2 is an axially extending strip structure, the strip structure is a structure with a trapezoidal radial cross section, the bottom side of the trapezoidal structure is on the air gap side, and the size is D; the trapezoidal The top edge of the structure is on the rotor core side, with a size of B; the relationship is satisfied: D>B; a limiting groove 3-4 with a trapezoidal cross-section is provided at the lower clamping end 3-2, the opening of the limiting groove 3-4 is located on the inner side of the lower clamping end 3-2, the trapezoidal bottom edge of the limiting groove 3-4 is at the opening end, with a size of B, the trapezoidal top edge of the limiting groove 3-4 is at the bottom of the groove, with a size of E, the trapezoidal height of the limiting groove 3-4 is equal to the height of the lower trapezoid of the permanent magnet positioning tooth 2-1, and the limiting groove 3-4 is used to embed the strip structure where the lower trapezoid of the permanent magnet positioning tooth 2-1 is located.

[0009] Preferably, the housing 4 is made of aluminum alloy.

[0010] Preferably, the sizes of the P installation grooves on the inner circular surface of the housing 4 match the upper clamping end 3 - 1 of the C-shaped connector 3 , and the two form a mortise and tenon structure.

[0011] Preferably, the torque T of the motor includes the electromagnetic torque T e and reluctance torque T r Two parts, reluctance torque T r Calculate it by the following formula:

[0012]

[0013] Where p is the number of pole pairs of the motor, L d is the direct-axis inductance, L q is the quadrature-axis inductance, I rms is the effective value of the motor rotor current, and β is the angle between the permanent magnet magnetic field and the rotor.

[0014] Beneficial effects of the invention: The invention provides a new assembly scheme, which uses a C-shaped connector to assemble the rotor core and the housing together, and limits the permanent magnet. This assembly method can not only strengthen the connection between the rotor and the housing, effectively fix the permanent magnet, prevent the permanent magnet from falling off, prevent the rotor from deforming under harsh working conditions, improve the rotor stiffness, ensure the roundness, reduce the risk of eccentricity, and ensure the stability of the hub operation, but also use this structure to increase the torque and reduce vibration noise. And it can also further increase the torque of the hub motor.

[0015] The present invention can conveniently fix the permanent magnet by fixing it on the permanent magnet positioning groove of the rotor. Compared with the traditional permanent magnet gluing fixing method, the new structure fixing method is not easy to fall off, ensuring that the outer rotor of the hub motor can work under more severe working conditions. In addition, the protrusion of the positioning groove can further improve the torque by utilizing the magnetic resistance torque that the traditional surface-mounted motor cannot utilize. The most suitable protrusion height is found through a reasonable EA evolutionary algorithm to achieve the best performance, reduce magnetic leakage, and improve torque.

[0016] On this basis, the permanent magnet, outer rotor and casing are fixed together through a C-type structure, which can better fix the outer rotor to ensure the roundness of the outer rotor, reduce the possibility of eccentricity of the outer rotor, ensure the smooth operation of the motor, and improve the overall stiffness of the outer rotor. It can reduce the deformation of the outer rotor caused by electromagnetic vibration, reduce vibration noise, and bring a quieter driving environment for the driver of the vehicle.

[0017] The present invention realizes the characteristics of easy and reliable installation during the installation process; in terms of operation, it ensures that the motor can run stably and reduces the risk of eccentricity; and it improves the performance in many aspects, increases the torque and reduces the vibration noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is an exploded view of a hub motor with an outer rotor structure according to the present invention, without an inner stator;

[0019] Figure 2 It is an exploded view of a hub motor with an outer rotor structure according to the present invention, plus an inner stator;

[0020] Figure 3 It is a schematic diagram of the structure of the C-type connector loaded in the casing;

[0021] Figure 4 It is a schematic diagram of the process of assembling the permanent magnet and the rotor core to the casing;

[0022] Figure 5 It is a schematic diagram of the structure after the permanent magnet, rotor core and casing are assembled;

[0023] Figure 6 is Figure 4 Schematic diagram of the structure after the casing is cut in half, forward direction;

[0024] Figure 7 is Figure 4 Schematic diagram of the structure after the basic casing is cut in half, another angle of view;

[0025] Figure 8 It is a schematic diagram of the process of assembling the rotor core and the permanent magnet using a C-type connector;

[0026] Fig. 9 It is a schematic diagram of the structure after the rotor core and the permanent magnet are assembled;

[0027] Fig.10 yes Figure 8 A partial enlarged view of

[0028] Fig.11 This is the dimensioning diagram of the rotor core after the permanent magnets are assembled;

[0029] Fig.12 yes Fig.10 Dimensional drawing of the permanent magnet positioning teeth of the middle core;

[0030] Fig.13 yes Fig.10 Dimensional drawing of the permanent magnet part;

[0031] Fig.14 It is a schematic diagram of the DQ axis under each pole of the rotor;

[0032] Fig.15 It is a schematic diagram of the structure of a C-type connector;

[0033] Fig.16 This is the dimensioning drawing of the C-type connector. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0036] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0037] Specific implementation method 1: The following is combined Figures 1 to 16 The present embodiment is described. The present embodiment describes a wheel hub motor with an outer rotor structure. The wheel hub motor comprises an outer rotor, an inner stator 5 and a casing 4. The outer rotor comprises a permanent magnet 1, a rotor core 2 and a C-shaped connector 3. The inner surface of the casing 4 is uniformly provided with P mounting grooves along the circumferential direction. The C-shaped connector 3 assembles the rotor core 2 to the inside of the casing 4. The inner stator 5 is arranged inside the outer rotor, and there is a radial gap between the two.

[0038] On the inner circumferential surface of the rotor core 2, P permanent magnet positioning teeth 2-1 are evenly distributed along the circumferential direction. Between two adjacent permanent magnet positioning teeth 2-1, a permanent magnet 1 is inserted in a mortise and tenon manner. The upper clamping ends of the P C-shaped connectors 3 are respectively assembled with the P installation grooves on the inner circumferential surface of the machine housing 4 in a mortise and tenon manner. The lower clamping ends of the P C-shaped connectors 3 are respectively fitted and assembled with the end parts of the P permanent magnet positioning teeth 2-1, and the P C-shaped connectors 3 and the P permanent magnets 1 are kept on the same roundness.

[0039] The permanent magnet positioning teeth 2-1 of the rotor core 2 are axially extended strip structures, and the radial cross-section is two trapezoidal structures with the same bottom. Among them, the top side of the upper trapezoid is connected to the yoke part of the rotor core 2, and the dimension is A; the bottom side of the upper trapezoid coincides with the bottom side of the lower trapezoid, and the dimension is B, and the top side of the lower trapezoid is close to the air gap side, and the dimension is E, satisfying the relationship: A < B, E < B, and the distance from the top side of the lower trapezoid to the air gap side is F.

[0040] The permanent magnet 1 is composed of a single permanent magnet block or multiple permanent magnet blocks arranged in parallel. The tangential dimension of the permanent magnet 1 on the rotor yoke side is G, and the tangential dimension of the permanent magnet 1 on the air gap side is H, satisfying the relationship: G > H. The permanent magnet 1 and the two adjacent permanent magnet positioning teeth 2-1 form a mortise and tenon structure.

[0041] A permanent magnet positioning groove is formed between two permanent magnet positioning teeth 2-1. Since the permanent magnet positioning groove has the characteristic of being narrow on the air gap side, its fixation with the permanent magnet 1 is approximately a mortise and tenon structure, which can ensure that the two are tightly combined together.

[0042] The C-shaped connector 3 includes an upper clamping end 3-1, a lower clamping end 3-2 and an intermediate connector 3-3; the upper clamping end 3-1 and the lower clamping end 3-2 are axially extended strip structures. The radial cross-section of the upper clamping end 3-1 is a trapezoidal structure, and the bottom side of the trapezoidal structure is on the machine housing side, and the dimension is I; the top side of the trapezoidal structure is on the rotor core side, and the dimension is N; satisfying the relationship: I > N; the lower clamping end 3-2 is an axially extended strip structure, and the strip structure is a trapezoidal structure in the radial cross-section. The bottom side of the trapezoidal structure is on the air gap side, and the dimension is D; the top side of the trapezoidal structure is on the rotor core side, and the dimension is B; satisfying the relationship: D > B; a limiting groove 3-4 with a trapezoidal cross-section is opened on the lower clamping end 3-2. The opening of the limiting groove 3-4 is located on the inner side surface of the lower clamping end 3-2. The trapezoidal bottom side of the limiting groove 3-4 is at the opening end, and the dimension is B. The trapezoidal top side of the limiting groove 3-4 is at the bottom of the groove, and the dimension is E. The trapezoidal height of the limiting groove 3-4 is equal to the lower trapezoidal height of the permanent magnet positioning tooth 2-1. The limiting groove 3-4 is used to embed the strip structure where the lower trapezoid of the permanent magnet positioning tooth 2-1 is located.

[0043] The intermediate connector 3-3 of the C-shaped connector 3 is connected to the tails of the upper clamping end 3-1 and the lower clamping end 3-2. The height dimension of the intermediate connector 3-3 is K, and the outer dimensions of the radial lengths of the upper clamping end 3-1 and the lower clamping end 3-2 are M and L respectively.

[0044] The C-type connector 3 plays a role in ensuring roundness and reducing vibration noise. The lower clamping end 3-2 of the C-type connector 3 is clamped on the permanent magnet positioning tooth 2-1 of the rotor core 2, and the upper clamping end 3-1 is located on the housing 4. The size of the P installation grooves on the inner surface of the housing 4 matches the upper clamping end 3-1 of the C-type connector 3, and the two form a mortise and tenon structure, which can tightly fix the rotor core 2 and the housing 4.

[0045] The housing 4 is made of aluminum alloy, which has high rigidity and is not easily deformed, and is tightly fixed to the rotor core, so that the rotor is not easily deformed either.

[0046] The rotor structure described in this embodiment can not only be tightly combined but also improve the torque. The principle is to utilize the reluctance torque of the motor. The torque source of the motor can be divided into two parts, electromagnetic torque and reluctance torque. For a general surface-mounted rotor, the torque source is only electromagnetic torque and does not utilize reluctance torque. The feature of the present invention is that the permanent magnet positioning teeth protruding on the outer rotor can generate reluctance torque, which is improved compared to the surface-mounted permanent magnet motor torque.

[0047] The reluctance torque originates from the inconsistency of the reluctance of the D-axis and Q-axis in the magnetic circuit. In a permanent magnet synchronous motor, because the magnetic flux always prefers to take the path with the smallest reluctance, the inconsistency of the reluctance of the two axes causes the magnetic flux to be biased in path selection. Under the same current, the greater the difference in reluctance between the DQ axes, the greater the reluctance torque. Since the magnetic permeability of the permanent magnet is basically the same as the magnetic permeability of the air gap, and the magnetic permeability of the iron core is much greater than the magnetic permeability of the air, the magnetic flux flows more in the iron core. Due to the presence of the permanent magnet positioning groove, the present invention has two parts, the permanent magnet and the air gap, on the direct axis, and only the air gap on the cross axis, resulting in the inconsistency between the cross-axis reluctance and the direct-axis reluctance, resulting in a reluctance torque.

[0048] The motor torque T includes the electromagnetic torque T e and reluctance torque T r Two parts, reluctance torque T r Calculate it by the following formula:

[0049]

[0050] Where p is the number of pole pairs of the motor, L d is the direct-axis inductance, L q is the quadrature-axis inductance, I rms is the effective value of the motor rotor current, and β is the angle between the permanent magnet magnetic field and the rotor.

[0051] The torque of the motor is divided into two parts, the first part is the electromagnetic torque, and the second part is the reluctance torque. The reluctance torque comes from the difference between the D-axis reluctance and the Q-axis reluctance. The greater the difference, the greater the increased reluctance torque. In other words, the longer the protruding length of the permanent magnet positioning tooth 2-1, the greater the increased reluctance torque. However, the present invention does not protrude the longest protruding length of the tooth to the same height as the magnetic steel, but is slightly shorter than the permanent magnet height F. The reason is that excessive protruding length will cause more serious magnetic leakage in the motor, which will reduce the torque. The shape of the protruding tooth is optimized by the EA evolutionary algorithm to find the best shape as the shape of the present invention, which maximizes the torque and reduces magnetic leakage.

[0052] As a further improvement measure of the present invention, in order to solve the problems of poor rotor roundness and large vibration noise, a C-type connector 3 is proposed. This structure is located between the housing 4 and the rotor core 2 and plays a fixing role. The shape of the lower clamping end 3-2 of the C-type connector 3 is consistent with the shape of the lower trapezoid of the permanent magnet positioning tooth 2-1. The lower clamping end 3-2 can be matched with the permanent magnet positioning tooth 2-1 to ensure that the roundness of the outer rotor will not be affected by external effects, and the stable operation of the motor will not be changed due to changes in the external environment, thereby reducing the risk of motor eccentricity and facilitating the stable operation of the motor.

[0053] The motor vibration is judged by the following formula:

[0054]

[0055] In the formula, Y1 and Y2 are the vibration displacements of the rotor core and the casing of the motor, respectively, Pn is the concentrated force that causes the motor vibration, K1 and K2 are the stiffness of the motor rotor core and the casing, m1 and m2 are the mass of the rotor core and the casing, respectively, and ω is the frequency of the concentrated force that causes the motor vibration. As can be seen from the formula, the greater the stiffness and the smaller the mass, the smaller the vibration displacement of the motor. Among them, stiffness usually refers to the ability to resist deformation, which is a proportional coefficient directly between force and displacement. The size of the stiffness depends on the geometry of the parts and the type of material. The greater the stiffness of the outer rotor, the stronger the motor's ability to resist deformation and the better the vibration reduction and noise reduction effect.

[0056] The above formula shows that the material of the C-type connector 3 cannot be magnetic (to prevent more serious magnetic leakage), and it needs to have characteristics such as large Young's modulus, small Poisson's ratio, and small density. The above characteristics are to improve the rigidity of the outer rotor. In this embodiment, the C-type connector 3 is made of aluminum alloy material, which can meet the above characteristics and is easy to process, assemble and produce. Therefore, the addition of the C-type connector 3 can achieve the effect of reducing vibration noise.

[0057] The assembly method of this embodiment is as follows: the permanent magnet 1 can be first installed on the rotor core 2 to achieve a tight fit similar to a mortise and tenon structure, and then the lower clamping end 3-2 of the C-shaped connector 3 is inserted into the permanent magnet positioning tooth 2-1 on the rotor 2 between the permanent magnets 1 to further tightly fix the permanent magnet 1 and the rotor core 2, and finally the upper clamping end 3-1 of the C-shaped connector 3 is inserted from the tail into the installation groove of the casing to achieve a tight fit similar to a mortise and tenon structure with the casing 4 to complete the installation.

[0058] Alternatively, the upper clamping end 3-1 of the C-shaped connector 3 may be inserted into the mounting groove of the casing from the rear, and then the rotor core may be inserted into the C-shaped connector 3 so that the permanent magnet positioning tooth 2-1 is inserted into the limiting groove 3-4 of the lower clamping end 3-2 of the C-shaped connector 3.

[0059] The assembly order is relatively random and the assembly is easy.

[0060] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that the features described in conjunction with a single embodiment may be used in other described embodiments.

Claims

1. A hub motor with an outer rotor structure, characterized in that: The in-wheel motor includes an outer rotor, an inner stator (5) and a housing (4). The outer rotor includes a permanent magnet (1), a rotor core (2) and a C-shaped connecting member (3). The inner circumferential surface of the housing (4) is evenly distributed with P mounting grooves along the circumferential direction. The C-shaped connecting member (3) assembles the rotor core (2) inside the housing (4). The inner stator (5) is arranged inside the outer rotor, and there is a radial gap between them. The inner circumferential surface of the rotor core (2) is evenly distributed with P permanent magnet positioning teeth (2-1) along the circumferential direction. A permanent magnet (1) is embedded between two adjacent permanent magnet positioning teeth (2-1) in a mortise and tenon manner. The upper clamping ends of the P C-shaped connecting members (3) are respectively assembled with the P mounting grooves on the inner circumferential surface of the housing (4) in a mortise and tenon manner. The lower clamping ends of the P C-shaped connecting members (3) are respectively fitted and assembled with the end parts of the P permanent magnet positioning teeth (2-1), and the P C-shaped connecting members (3) and the P permanent magnets (1) are kept on the same roundness.

2. The wheel hub motor with an outer rotor structure according to claim 1, characterized in that: The permanent magnet positioning teeth (2-1) of the rotor core (2) are axially extending strip-shaped structures, and the radial cross-section is two trapezoidal structures with the same bottom. The top side of the upper trapezoid is connected to the yoke part of the rotor core (2), and the dimension is A. The bottom side of the upper trapezoid coincides with the bottom side of the lower trapezoid, and the dimension is B. The top side of the lower trapezoid is close to the air gap side, and the dimension is E, satisfying the relationship: A < B, E < B. The distance from the top side of the lower trapezoid to the air gap side is F.

3. The wheel hub motor with an outer rotor structure according to claim 2, characterized in that: The permanent magnet (1) is composed of a single permanent magnet block or multiple permanent magnet blocks arranged side by side. The tangential dimension of the permanent magnet (1) on the rotor yoke side is G, and the tangential dimension of the permanent magnet (1) on the air gap side is H, satisfying the relationship: G > H. The permanent magnet (1) and the adjacent two permanent magnet positioning teeth (2-1) form a mortise and tenon structure.

4. The wheel hub motor with an outer rotor structure according to claim 2, characterized in that: The C-shaped connecting member (3) includes an upper clamping end (3-1), a lower clamping end (3-2) and an intermediate connecting member (3-3). The upper clamping end (3-1) and the lower clamping end (3-2) are axially extending strip-shaped structures. The radial cross-section of the upper clamping end (3-1) is a trapezoidal structure. The bottom side of the trapezoidal structure is on the housing side, and the dimension is I. The top side of the trapezoidal structure is on the rotor core side, and the dimension is N, satisfying the relationship: I > N. The lower clamping end (3-2) is an axially extending strip-shaped structure, and the strip-shaped structure is a trapezoidal structure in the radial cross-section. The bottom side of the trapezoidal structure is on the air gap side, and the dimension is D. The top side of the trapezoidal structure is on the rotor core side, and the dimension is B, satisfying the relationship: D > B. A limiting groove (3-4) with a trapezoidal cross-section is opened in the lower clamping end (3-2). The opening of the limiting groove (3-4) is located on the inner side surface of the lower clamping end (3-2). The bottom side of the trapezoid of the limiting groove (3-4) is at the opening end, and the dimension is B. The top side of the trapezoid of the limiting groove (3-4) is at the bottom of the groove, and the dimension is E. The trapezoidal height of the limiting groove (3-4) is equal to the lower trapezoidal height of the permanent magnet positioning tooth (2-1). The limiting groove (3-4) is used to embed the strip-shaped structure where the lower trapezoid of the permanent magnet positioning tooth (2-1) is located.

5. The wheel hub motor with an outer rotor structure according to claim 1, characterized in that: The housing (4) is made of aluminum alloy material.

6. The wheel hub motor with an outer rotor structure according to claim 4, characterized in that: The dimensions of the P mounting grooves on the inner circumferential surface of the housing (4) match the upper clamping end (3-1) of the C-shaped connecting member (3), and the two form a mortise and tenon structure.

7. The wheel hub motor with an outer rotor structure according to claim 1, characterized in that: The motor torque T includes the electromagnetic torque T e and reluctance torque T r Two parts, reluctance torque T r Calculate it by the following formula: Where p is the number of pole pairs of the motor, L d is the direct-axis inductance, L q is the quadrature-axis inductance, I rms is the effective value of the motor rotor current, and β is the angle between the permanent magnet magnetic field and the rotor.

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