An electric motor and a vehicle

Abstract

This application relates to the field of motor technology, providing a motor and a vehicle. The motor includes a stator assembly and a rotor assembly, with the rotor assembly sleeved on the outside of the stator assembly. The magnetic poles include two permanent magnets, with their radially outer ends close to each other and their radially inner ends far apart. The rotor core forms a first cavity between the radially outer ends of the two permanent magnets. A magnetically conductive sliding member capable of sliding radially is disposed within the first cavity. The magnetically conductive sliding member has a first position and a second position, with the second position radially outside the first position. The elastic force of an elastic reset member holds the magnetically conductive sliding member in the first position, and the centrifugal force of the rotor assembly drives the magnetically conductive sliding member to move to the second position against the elastic force of the elastic reset member. By optimizing the rotor topology and magnetic circuit design of the motor, within a limited motor space, the rotor magnetic flux can be varied and adjusted during high-speed cruising, thereby improving the high-speed cruising efficiency of the motor and the high-speed cruising range of the entire vehicle.

Description

Technical Field

[0001] This application relates to the field of motor technology, specifically to a motor and a vehicle. Background Technology

[0002] As the power heart of new energy vehicles, electric motors face increasingly higher demands on high-speed cruising efficiency and overall high-speed cruising range. To meet these new requirements, a new type of motor is needed that can achieve adjustable rotor flux during high-speed cruising within a limited motor space, thereby improving the motor's high-speed cruising performance. Summary of the Invention

[0003] This application provides an electric motor and a vehicle. By optimizing the rotor topology and magnetic circuit design of the motor, the rotor magnetic flux can be varied and adjusted under high-speed cruising within a limited motor space, thereby improving the high-speed cruising efficiency of the motor and the high-speed cruising range of the entire vehicle.

[0004] The technical solution of this application embodiment is implemented as follows: This application provides an embodiment of a motor, including: Stator assembly; The rotor assembly is sleeved on the outside of the stator assembly. The rotor assembly includes a rotor core, multiple magnetic poles, multiple magnetic sliding members, and multiple elastic reset members. A portion of the magnetic poles are N poles and another portion of the magnetic poles are S poles. The N poles and the S poles are alternately arranged on the rotor core along the circumferential direction. The magnetic pole includes two permanent magnets, with their radially outer ends close to each other and their radially inner ends far apart. The rotor core is located between the radially outer ends of the two permanent magnets to form a first cavity, and a magnetically conductive sliding member that can slide radially is provided in the first cavity. The magnetically conductive slider has a first position and a second position, the second position being radially outside the first position. The elastic force of the elastic reset member holds the magnetically conductive slider in the first position, and the centrifugal force of the rotor assembly drives the magnetically conductive slider to move to the second position against the elastic force of the elastic reset member.

[0005] The motor provided in this application embodiment has a rotor assembly mounted outside the stator assembly, resulting in a larger radius of rotation for the rotor assembly. At the same speed, the magnetically guided sliding element receives a greater centrifugal force, allowing the vehicle to stably enter passive magnetic weakening mode within its commonly used high-speed cruising range, thus facilitating coverage of common vehicle speeds. The radially outer ends of the two permanent magnets are close to each other, while their radially inner ends are far apart. The first cavity is located between the radially outer ends of the two permanent magnets. The magnetically guided sliding element can switch between a first position and a second position under the combined action of the elastic reset element and centrifugal force. When the rotor assembly is stationary or at low speed, the vehicle is stationary or at low speed, and the centrifugal force generated by the rotor assembly is relatively small, unable to overcome the elastic force generated by the elastic reset element. The magnetically guided sliding element remains in the first position. The magnetic flux of the third magnetic bridge between the radially outer ends of the permanent magnets and the first cavity is saturated. The magnetic flux flow through the third magnetic bridge is restricted, and there is no magnetic leakage due to coupling between the magnetic poles and the magnetically guided sliding element. Almost all the permanent magnet flux of the N and S poles enters the air gap to form an alternating main magnetic field, resulting in the highest magnetic flux density in the air gap, ensuring the motor's power performance in the constant torque range. When the rotor assembly is at high speed, the vehicle is in high-speed cruising condition. The centrifugal force generated by the rotor assembly increases, which can overcome the elastic force generated by the elastic reset component. This drives the magnetic sliding component to move radially outward to the second position under the action of centrifugal force. The magnetic flux flow of the magnetic circuit flows through the magnetic sliding component. The magnetic sliding component establishes a magnetic flux bypass between the two permanent magnets of the same pole, thereby allowing an increase in leakage flux and reducing rotor core losses at high speed and high frequency. This achieves passive adjustment of the magnetic flux flow of the magnetic circuit without the need for an active adjustment mechanism. Thus, by optimizing the rotor topology and magnetic circuit design of the motor, the rotor magnetic flux can be varied and adjusted under high-speed cruising within the limited motor space, thereby improving the high-speed cruising efficiency of the motor and the high-speed cruising range of the entire vehicle.

[0006] In some embodiments, the elastic reset member is disposed within the first cavity, and the elastic reset member is connected to the outer end of the magnetically conductive slider in the radial direction.

[0007] In this embodiment, the elastic reset member is disposed within the first cavity, which not only facilitates fixing the elastic reset member but also helps prevent other components from interfering with the deformation of the elastic reset member. The elastic reset member is connected to the outer end of the magnetically conductive slider in the radial direction, which can prevent the elastic reset member from interfering with the radial sliding of the magnetically conductive slider.

[0008] In some embodiments, the rotor core forms a boss protruding toward the first cavity, the boss being located radially outside the magnetically conductive slider, the boss being used to confine the magnetically conductive slider to the second position.

[0009] In this embodiment, the magnetic sliding member moves to the second position under the action of centrifugal force and abuts against the boss. The boss is used to limit the magnetic sliding member to the second position, thereby limiting the maximum stroke of the magnetic sliding member to move radially outward. This ensures that the coupling degree between the magnetic sliding member and the permanent magnet remains stable and controllable under high-speed cruise conditions. The magnetic flux shunting ratio will not change abruptly due to the overtravel offset of the magnetic sliding member, thus stably achieving the effect of high-speed shunting and reducing magnetic flux, improving the reliability of high-speed motor operation and cruise efficiency.

[0010] In some embodiments, the circumferential dimension of the boss is 0.4mm-1.2mm.

[0011] In this embodiment, the circumferential dimension of the boss is 0.4mm-1.2mm. The appropriate size of the boss protruding into the first cavity provides good structural strength and stable contact with the magnetic sliding component to limit its movement. This also avoids the boss's excessive circumferential dimension from encroaching on the effective arrangement space of the cavity. Furthermore, it facilitates the integral stamping of the rotor core laminations, reducing processing risks and balancing the reliability of the limiting position, the magnetic isolation performance of the magnetic circuit, and the processability.

[0012] In some embodiments, the first cavity is filled with a lubricating medium.

[0013] In this embodiment, the first cavity is filled with a lubricating medium, which can continuously form an oil film to lubricate the mating friction surface between the magnetic sliding member and the cavity wall, reducing the resistance during the reciprocating sliding process of the magnetic sliding member. The lubricating medium can also carry away the heat conducted by the sliding friction of the magnetic sliding member and the surrounding permanent magnets, suppressing the temperature rise and demagnetization of the permanent magnets. The lubricating medium will not change the equivalent magnetic resistance of the air between the magnetic sliding member and the cavity wall and the permanent magnets, and the passive magnetic flux shunting characteristics are basically unaffected.

[0014] In some embodiments, the gap between the magnetically conductive slider and the wall of the first cavity is greater than 0 mm and less than 0.1 mm in the circumferential direction.

[0015] In this embodiment, the gap between the magnetically conductive slider and the wall of the first cavity is greater than 0 mm and less than 0.1 mm. The gap fit between the magnetically conductive slider and the first cavity is beneficial for the magnetically conductive slider to slide in the first cavity, and can also limit the circumferential swing and offset of the magnetically conductive slider during the sliding process, which is beneficial for maintaining the smooth radial sliding of the magnetically conductive slider.

[0016] In some embodiments, the rotor core forms a plurality of second cavities spaced apart circumferentially, and the permanent magnet is embedded in the second cavity.

[0017] In this embodiment, the permanent magnet is embedded in the second cavity. The solid structure of the rotor core can constrain and protect the permanent magnet, reducing the risk of the permanent magnet falling off or shifting due to centrifugal force during rotation. This improves the mechanical reliability and overall strength of the rotor assembly, and also enhances the demagnetization resistance of the permanent magnet, extending the service life of the motor.

[0018] In some embodiments, the portion of the rotor core located between the radial inner end and the radial inner edge of the second cavity is a first magnetic bridge, and the radial dimension of the first magnetic bridge is 1.05mm-1.1mm.

[0019] In this embodiment, the radial dimension of the first magnetic bridge is 1.05mm-1.1mm, which reduces the leakage flux, avoids excessive magnetic flux loss, and helps improve the utilization rate of the permanent magnet, thereby increasing the torque output and power density of the motor. It also avoids the problem of insufficient mechanical strength caused by excessive narrowing of the first magnetic bridge, which helps maintain the overall rigidity of the rotor core structure, allowing the rotor core to withstand the centrifugal force impact under high-speed rotation, meeting the requirements for mechanical stability in high-speed operation scenarios, reducing magnetic flux flow while meeting mechanical strength requirements, and balancing the electromagnetic performance of the motor with the structural reliability of long-term operation.

[0020] In some embodiments, the portion of the rotor core located between two adjacent second cavities is a second magnetic bridge, and the second magnetic bridge has a circumferential dimension of 1.4mm-1.7mm.

[0021] In this embodiment, the second magnetic bridge has a circumferential dimension of 1.4mm-1.7mm, which makes it easier for the second magnetic bridge to enter the magnetic saturation state, reduces the leakage flux of the permanent magnet, improves the utilization rate of the permanent magnet, and helps the motor achieve higher torque density and operating efficiency. It also helps to maintain the overall rigidity of the rotor core structure, avoids problems such as insufficient local rigidity and stress concentration, and ensures that the rotor core can withstand sufficient centrifugal force when rotating at high speed, meeting the requirements for mechanical stability in high-speed operating scenarios.

[0022] In some embodiments, the portion of the rotor core located between the first cavity and the second cavity is a third magnetic bridge, and the circumferential dimension of the third magnetic bridge is 0.95mm-1.05mm.

[0023] In this embodiment, the circumferential dimension of the third magnetic bridge is 0.95mm-1.05mm, which makes it easier for the third magnetic bridge to enter the magnetic saturation state. This prevents the permanent magnet flux from forming a fixed bypass leakage flux through the third magnetic bridge. When the rotor assembly is stationary or at low speed, the magnetically guided sliding element remains in the first position, the magnetic flux of the third magnetic bridge is saturated, and the flow of magnetic flux through the magnetic circuit is restricted. There is no magnetic flux leakage coupled to the magnetic poles by the magnetically guided sliding element. This ensures that the permanent magnet flux enters the air gap as much as possible to maintain sufficient output torque under stationary or low-speed conditions. It also meets the mechanical structural strength requirements of the rotor assembly when it is running at high speed, which is beneficial to maintaining the overall rigidity of the rotor core structure and avoiding problems such as insufficient local rigidity and stress concentration. It can ensure that the rotor core can withstand sufficient centrifugal force when rotating at high speed, meeting the mechanical stability requirements under high-speed operation scenarios. It also works with the magnetically guided sliding element in the first cavity to achieve adaptive magnetic flux passive adjustment, improving the high-speed cruising efficiency of the motor and the driving range of the whole vehicle.

[0024] In some embodiments, the rotor assembly rotates at a preset speed, and the magnetic sliding member moves to the second position.

[0025] In this embodiment, the centrifugal force on the magnetic sliding member can be determined by designing a preset rotation speed. When the rotation speed of the rotor assembly reaches the preset speed, the centrifugal force on the magnetic sliding member is greater than the current elastic force, and the magnetic sliding member reaches the critical point of moving radially outward. The magnetic sliding member can then move radially outward to the second position.

[0026] This application provides a vehicle, including: Vehicle body; The motor described in any one of the above embodiments is mounted on the vehicle body and is used to drive the vehicle body to move. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the motor in some embodiments of this application; Figure 2 for Figure 1 A schematic diagram of the middle part of the structure, in which the magnetically conductive sliding component is in the first position; Figure 3 for Figure 2 A schematic diagram of the magnetic flux flow of the structure shown. Figure 4 for Figure 2 A schematic diagram of another state of the structure shown, in which the magnetically conductive slider is in the second position; Figure 5 for Figure 4 A schematic diagram of the magnetic flux flow of the structure shown.

[0028] Explanation of reference numerals in the attached figures 1. Stator assembly; 11. Stator core; 11a. Stator slot; 111. Stator pole shoe; 112. Stator pole body; 12. Stator winding; 2. Rotor assembly; 21. Rotor core; 21a. First cavity; 21b. Second cavity; 211. Boss; 212. First magnetic bridge; 213. Second magnetic bridge; 214. Third magnetic bridge; 22. Magnetic pole; 221. Permanent magnet; 23. Magnetic sliding component; 24. Elastic reset component. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, embodiments of the technical solutions of this application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solutions of this application more clearly, and are therefore merely examples and should not be used to limit the scope of protection of this application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this application.

[0031] In the description of the embodiments of this application, the technical terms "first", "second", etc. are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0032] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that combinations can be made in any suitable manner without contradiction; for example, different combinations of specific technical features / embodiments can form different implementations. To avoid unnecessary repetition, the various possible combinations of specific technical features / embodiments in this application will not be described separately.

[0033] It should be noted that the illustrations provided in the embodiments are only schematic representations of the basic concept of this application. Therefore, the drawings only show the components related to this application and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0034] It should be noted that in this application, "multiple" includes two or more.

[0035] This application provides a vehicle, including a vehicle body and a motor as described in any one of the embodiments of this application. The motor is mounted on the vehicle body and is used to drive the vehicle body to move.

[0036] The type of vehicle is not limited; for example, the vehicle can be a pure electric vehicle or a hybrid vehicle, etc.

[0037] The electric motor serves as the power source for the vehicle, driving its movement. The vehicle body consists of the frame and four wheels, with the electric motor driving the wheels to roll.

[0038] Please see Figure 1 The motor provided in this embodiment includes a stator assembly 1 and a rotor assembly 2. The rotor assembly 2 is sleeved on the outside of the stator assembly 1.

[0039] Please see Figure 1 , Figure 2 and Figure 4 The rotor assembly 2 includes a rotor core 21, multiple magnetic poles 22, multiple magnetically conductive sliding members 23, and multiple elastic reset members 24. Some of the magnetic poles 22 are N poles, and the other part are S poles, with the N and S poles alternately spaced circumferentially on the rotor core 21. Each magnetic pole 22 includes two permanent magnets 221, with their radially outer ends close to each other and their radially inner ends far apart. A first cavity 21a is formed in the rotor core 21 between the radially outer ends of the two permanent magnets 221. A magnetically conductive sliding member 23 capable of sliding radially is disposed within the first cavity 21a. The magnetically conductive sliding member 23 has a first position and a second position. The second position is radially outside the first position. The elastic force of the elastic reset members 24 holds the magnetically conductive sliding member 23 in the first position, while the centrifugal force of the rotor assembly 2 drives the magnetically conductive sliding member 23 to move to the second position against the elastic force of the elastic reset members 24.

[0040] The rotor assembly 2 and the stator assembly 1 are arranged concentrically. The rotor core 21 surrounds the outer periphery of the stator assembly 1. There is an air gap between the rotor core 21 and the stator assembly 1, that is, the rotor core 21 and the stator assembly 1 are spaced apart.

[0041] Each N-pole or S-pole magnetic pole 22 adopts: two permanent magnets 221 roughly forming a V-shaped structure, with the tip of the V-shaped structure facing radially outward.

[0042] In the circumferential direction, the N-pole 22 and the S-pole 22 are arranged alternately, and two adjacent poles 22 are opposite polarity poles 22. The motor is a permanent magnet synchronous motor.

[0043] In some embodiments, the structures of each magnetic pole 22 may be identical, and the multiple magnetic poles 22 may be evenly distributed circumferentially. In this way, the number of N poles and S poles are equal and correspond one-to-one.

[0044] The N poles and S poles are arranged alternately along the circumference, and the permanent magnet magnetic field sequentially flows from the N pole, the air gap, the stator core 11, and then to the adjacent S pole, forming a closed main magnetic circuit.

[0045] The first cavity 21a is located between the radial outer ends of the two permanent magnets 221 of each magnetic pole 22. That is, the first cavity 21a is close to the radial outer side of the rotor core 21, and the magnetic sliding member 23 is also close to the radial outer side of the rotor core 21.

[0046] The magnetically conductive sliding member 23 can switch between the first position and the second position under the combined action of the elastic reset member 24 and the centrifugal force.

[0047] Please see Figure 2 and Figure 3 When the rotor assembly 2 is stationary or at low speed, the vehicle is stationary or at low speed, such as when the vehicle is starting or climbing. The centrifugal force generated by the rotor assembly 2 is relatively small and cannot overcome the elastic force generated by the elastic reset member 24. The magnetic sliding member 23 remains in the first position. The magnetic flux of the third magnetic bridge 214 between the radial outer end of the permanent magnet 221 and the first cavity 21a is saturated. The magnetic flux flow of the magnetic circuit is restricted by the third magnetic bridge 214. The magnetic pole 22 is coupled with leakage magnetic flux without the magnetic sliding member 23. The permanent magnet flux of the N pole and the S pole almost all enters the air gap to form an alternating main magnetic field. The air gap magnetic flux density is the highest to ensure the power performance of the motor in the constant torque range.

[0048] Please see Figure 4 and Figure 5 When the rotor assembly 2 is in a high-speed state, the vehicle is in a high-speed cruising condition, for example, when the vehicle speed is 80km / h or above. The centrifugal force generated by the rotor assembly 2 increases, which can overcome the elastic force generated by the elastic reset member 24 and drive the magnetic sliding member 23 to move radially outward to the second position under the action of centrifugal force. The magnetic flux flow of the magnetic circuit flows through the magnetic sliding member 23. The magnetic sliding member 23 establishes a magnetic flux bypass between the two permanent magnets 221 with the same pole, thereby allowing the increase of leakage flux, reducing the loss of the rotor core 21 at high speed and high frequency, and thus improving the high-speed cruising efficiency of the motor and the high-speed cruising range of the whole vehicle.

[0049] The unit "km / h" means kilometers per hour.

[0050] In some embodiments, the magnetically conductive slider 23 is located on the d-axis of the two permanent magnets 221 of each magnetic pole 22. That is, the magnetically conductive slider 23 is located at the symmetrical position between the two permanent magnets 221 of each magnetic pole 22.

[0051] It should be noted that, in the embodiments of this application, the axial direction refers to the direction along the rotation axis of the rotor assembly 2; the radial direction is perpendicular to the axial direction and along the radius, wherein the direction pointing towards the axis in the radial direction is the radial inner side, and the direction away from the axis in the radial direction is the radial outer side; the circumferential direction is the circumferential direction around the rotation axis, and both the axial and radial directions are perpendicular to the circumferential direction.

[0052] The outer radial end of the permanent magnet 221 is the end of the permanent magnet 221 that is close to the outer radial direction in the radial direction, and the inner radial end is the end of the permanent magnet 221 that is close to the inner radial direction in the radial direction.

[0053] The motor provided in this application embodiment has a rotor assembly 2 mounted on the outside of the stator assembly 1. The rotor assembly 2 has a larger radius of rotation, and the magnetic sliding member 23 obtains a larger centrifugal force at the same speed. The vehicle can stably enter the passive magnetic weakening condition in the commonly used high-speed cruising range, which is beneficial for covering the commonly used vehicle speed. The radial outer ends of the two permanent magnets 221 are close to each other, while the radial inner ends are far apart. The first cavity 21a is located between the radial outer ends of the two permanent magnets 221. The magnetic sliding member 23 can switch between the first position and the second position under the combined action of the elastic reset member 24 and the centrifugal force. When the rotor assembly 2 is stationary or at low speed, the vehicle is stationary or at low speed. The centrifugal force generated by the rotor assembly 2 is relatively small and cannot overcome the elastic force generated by the elastic reset member 24. The magnetic sliding member 23 remains in the first position. The magnetic flux of the third magnetic bridge 214 between the radial outer end of the permanent magnet 221 and the first cavity 21a is saturated. The magnetic flux flow of the magnetic circuit is restricted by the flow of the third magnetic bridge 214. The magnetic pole 22 is not coupled with the magnetic leakage of the magnetic pole 22. The permanent magnet flux of the N pole and the S pole almost all enters the air gap to form an alternating main magnetic field. The magnetic flux density of the air gap is the highest to ensure the power performance of the motor in the constant torque range. When the rotor assembly 2 is at high speed, the vehicle is in high-speed cruising condition. The centrifugal force generated by the rotor assembly 2 increases, which can overcome the elastic force generated by the elastic reset member 24. This drives the magnetic sliding member 23 to move radially outward to the second position under the action of centrifugal force. The magnetic flux flow of the magnetic circuit flows through the magnetic sliding member 23. The magnetic sliding member 23 establishes a magnetic flux bypass between the two permanent magnets 221 with the same pole, thereby allowing an increase in leakage flux, reducing the loss of the rotor core 21 at high speed and high frequency, and realizing passive adjustment of the magnetic flux flow of the magnetic circuit without the need for an active adjustment mechanism. In this way, by optimizing the rotor topology and magnetic circuit design of the motor, the rotor magnetic flux can be varied and adjusted under high-speed cruising within the limited motor space, thereby improving the high-speed cruising efficiency of the motor and the high-speed cruising range of the whole vehicle.

[0054] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4The stator assembly 1 includes a stator core 11 and a stator winding 12. The stator core 11 is formed with stator slots 11a, and the coils of the stator winding 12 are embedded in the stator slots 11a.

[0055] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The stator winding 12 adopts a double-layer winding in the stator slot 11a.

[0056] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The stator core 11 includes stator pole shoes 111 and stator pole bodies 112. The stator pole bodies 112 are located between two adjacent stator slots 11a. The stator pole shoes 111 are connected to the radial outer end of the stator pole bodies 112. The circumferential width of the stator pole shoes 111 is greater than the circumferential width of the stator pole bodies 112. There is an air gap between the stator pole shoes 111 and the rotor core 21.

[0057] The number of stator slots 11a is unlimited and can be set according to requirements. For example, please refer to [link to example]. Figure 1 The number of stator slots 11a is 18. Of course, the number of stator slots 11a can be more or less.

[0058] In some embodiments, the motor may further include a housing, within which both the stator assembly 1 and the rotor assembly 2 may be disposed. The housing may employ a known structure, which will not be described in detail herein.

[0059] The number of N-pole 22 and S-pole 22 is unlimited and can be set according to requirements. For example, please refer to [link to example]. Figure 1 There are a total of 12 magnetic poles 22, with 6 N-pole magnetic poles 22 and 6 S-pole magnetic poles 22. In the circumferential direction, the included angle between two adjacent magnetic poles 22 is 30° (unit degree).

[0060] The magnetically conductive slider 23 is magnetically conductive and can be made of a soft magnetic material. The type of soft magnetic material is not limited, but, for example, includes, but is not limited to, iron-based alloys.

[0061] In some embodiments, the magnetically conductive slider 23 can be a one-piece structure. That is, the magnetically conductive slider 23 can be manufactured using a one-piece molding process.

[0062] The shape of the magnetically conductive slider 23 is not limited. For example, the magnetically conductive slider 23 can be generally rectangular, and the length direction of the magnetically conductive slider 23 is parallel to the axial direction.

[0063] In some embodiments, the rotor assembly 2 reaches a preset rotational speed, and the magnetic sliding member 23 moves to a second position.

[0064] In this embodiment, the centrifugal force on the magnetic sliding member 23 can be determined by designing a preset rotation speed. When the rotation speed of the rotor assembly 2 reaches the preset rotation speed, the centrifugal force on the magnetic sliding member 23 is greater than the current elastic force, and the magnetic sliding member 23 reaches the critical point of moving radially outward. The magnetic sliding member 23 can then move radially outward to the second position.

[0065] Understandably, the preset RPM can be matched with the vehicle's high-speed cruising speed, and the required preset RPM can be set according to the vehicle's high-speed cruising speed.

[0066] In some embodiments, the preset rotational speed is 9000 rpm (revolutions per minute).

[0067] It should be noted that the preset speed can also be higher or lower.

[0068] In some embodiments, the vehicle speed during high-speed cruising is above 80 km / h.

[0069] It should be noted that the vehicle speed can be higher or lower during high-speed cruising.

[0070] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The elastic reset member 24 is disposed in the first cavity 21a, and the elastic reset member 24 is connected to the outer end of the magnetically conductive sliding member 23 in the radial direction.

[0071] In this embodiment, the elastic reset member 24 is disposed within the first cavity 21a, which not only facilitates the fixing of the elastic reset member 24, but also helps to prevent other components from interfering with the deformation of the elastic reset member 24. The elastic reset member 24 is connected to the outer end of the magnetically conductive slider 23 in the radial direction, which can prevent the elastic reset member 24 from interfering with the radial sliding of the magnetically conductive slider 23.

[0072] The type of elastic reset member 24 is not limited. In some embodiments, the elastic reset member 24 can be a spring, such as a coil spring.

[0073] In some embodiments, the elastic reset member 24 may also be connected to the inner end of the magnetically conductive slider 23 in the radial direction.

[0074] The elastic force of the elastic reset member 24 can be designed according to requirements. For example, it can be designed according to the centrifugal force required for the magnetic sliding member 23 to slide toward the second position, that is, it can be designed according to the preset speed of the rotor assembly 2 or the preset speed of the vehicle under high-speed cruising conditions.

[0075] In some embodiments, the elastic reset member 24 is a spring with a spring force coefficient of k. Under high-speed cruising conditions, the centrifugal force experienced by the magnetic sliding member 23 at the second position... ,in, For the mass of the magnetically conductive sliding member 23, Angular velocity, Let F be the radius of the circular motion, and F be the elastic force of the elastic reset member 24. k =-kx, where x is the deformation of the elastic reset member 24. Under high-speed cruising conditions, the centrifugal force on the magnetic sliding member 23 at the second position is equal to the elastic force. That is, the sliding distance of the magnetic sliding member 23 to the radially outward under the action of high-speed centrifugal force can be x, and the relative distance between the second position and the first position is x.

[0076] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The rotor core 21 forms a boss 211 protruding into the first cavity 21a. The boss 211 is located on the radial outer side of the magnetic sliding member 23 and is used to limit the magnetic sliding member 23 to the second position.

[0077] In this embodiment, the magnetic sliding member 23 moves to the second position under the action of centrifugal force and abuts against the boss 211. The boss 211 is used to limit the magnetic sliding member 23 to the second position, thereby limiting the maximum stroke of the magnetic sliding member 23 to move radially outward. This ensures that the coupling degree between the magnetic sliding member 23 and the permanent magnet 221 remains stable and controllable under high-speed cruise conditions. The magnetic flux shunting ratio will not change abruptly due to the overtravel offset of the magnetic sliding member 23, thus stably achieving the effect of high-speed shunting and reducing magnetic flux, and improving the reliability of high-speed motor operation and cruise efficiency.

[0078] In some embodiments, the boss 211 has a circumferential dimension of 0.4mm-1.2mm.

[0079] For example, the circumferential dimension of the boss 211 is any one of 0.4mm, 0.5mm, 0.7mm, 0.8mm, 1.0mm, 1.1mm and 1.2mm or a value between any two of them.

[0080] In this embodiment, the circumferential dimension of the boss 211 is 0.4mm-1.2mm. The size of the boss 211 protruding into the first cavity 21a is appropriate, the structural strength is good, and it can stably abut against the magnetic sliding member 23 to achieve the limiting of the magnetic sliding member 23. It can also avoid the boss 211 being too large in the circumferential dimension and occupying the effective arrangement space of the cavity. It is also conducive to the integral stamping of the rotor core 21 lamination, reducing the processing risk, and taking into account the reliability of the limiting, the magnetic isolation performance of the magnetic circuit and the processing technology.

[0081] It should be noted that in this application, the unit "mm" refers to millimeters.

[0082] The radial dimension of the boss 211 is not limited and can be set according to requirements. In some embodiments, the radial dimension of the boss 211 is 1.1mm-1.9mm.

[0083] For example, the radial dimension of the boss 211 is any one of 1.1mm, 1.2mm, 1.3mm, 1.5mm, 1.6mm, 1.8mm and 1.9mm or a value between any two of them.

[0084] In the embodiment where the elastic reset member 24 is connected to the radial outer end of the magnetically conductive sliding member 23, the boss 211 has a radial dimension of 1.1mm-1.9mm, which also facilitates the placement of the elastic reset member 24. Of course, depending on the deformation requirements of the elastic reset member 24, the radial dimension of the boss 211 can be larger or smaller.

[0085] In this embodiment, the radial dimension of the boss 211 is 1.1mm-1.9mm. The boss 211 has suitable structural strength and is also conducive to the integral stamping of rotor laminations.

[0086] The connection method between the elastic reset member 24 and the magnetic sliding member 23 is not limited. For example, the elastic reset member 24 and the magnetic sliding member 23 can be detachably connected or non-detachably connected.

[0087] The connection method between the elastic reset member 24 and the rotor core 21 is not limited. For example, the elastic reset member 24 and the rotor core 21 can be detachably connected or non-detachably connected.

[0088] Unless otherwise stated, in this application, detachable connections include, but are not limited to, snap-fit, screw connections, or bolt connections. Non-detachable connections include, but are not limited to, at least one of welding, bonding, and riveting.

[0089] In some embodiments, the first cavity 21a is filled with a lubricating medium.

[0090] In this embodiment, the first cavity 21a is filled with a lubricating medium, which can continuously form an oil film to lubricate the mating friction surface between the magnetic sliding member 23 and the cavity wall, reducing the resistance during the reciprocating sliding process of the magnetic sliding member 23. The lubricating medium can also carry away the heat conducted by the sliding friction of the magnetic sliding member 23 and the surrounding permanent magnet 221, and suppress the temperature rise and demagnetization of the permanent magnet 221. The lubricating medium will not change the equivalent magnetic resistance of the air between the magnetic sliding member 23 and the cavity wall and the permanent magnet 221, and the passive magnetic flux shunting characteristic is basically uninterrupted.

[0091] The type of lubricating medium is not limited. For example, the lubricating medium is not magnetic, including but not limited to silicone oil, etc.

[0092] In some embodiments, the gap between the magnetically conductive slider 23 and the wall of the first cavity 21a in the circumferential direction is greater than 0 mm and less than 0.1 mm.

[0093] For example, in the circumferential direction, the gap between the magnetically conductive slider 23 and the wall of the first cavity 21a can be any value of 0.01mm, 0.02mm, 0.05mm and 0.09mm or any two of them.

[0094] In this embodiment, the gap between the magnetically conductive slider 23 and the wall of the first cavity 21a is greater than 0 mm and less than 0.1 mm. The gap fit between the magnetically conductive slider 23 and the first cavity 21a is beneficial to the sliding of the magnetically conductive slider 23 in the first cavity 21a, and can also limit the circumferential swing and offset of the magnetically conductive slider 23 during the sliding process, which is beneficial to maintaining the smooth radial sliding of the magnetically conductive slider 23.

[0095] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The rotor core 21 forms multiple second cavities 21b spaced apart along the circumference, and the permanent magnet 221 is embedded in the second cavity 21b.

[0096] Specifically, a permanent magnet 221 can be embedded in each second cavity 21b.

[0097] For example, the permanent magnet 221 is fixed to the rotor core 21, and the fixing method is not limited. For example, the permanent magnet 221 can be interference-fitted with the second cavity 21b.

[0098] In this embodiment, the permanent magnet 221 is embedded in the second cavity 21b. The solid structure of the rotor core 21 can constrain and protect the permanent magnet 221, reducing the risk of the permanent magnet 221 falling off or shifting due to centrifugal force during rotation, improving the mechanical reliability and overall strength of the rotor assembly 2, and also improving the demagnetization resistance of the permanent magnet 221 and extending the service life of the motor.

[0099] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The part of the rotor core 21 located between the radial inner end and the radial inner edge of the second cavity 21b is the first magnetic bridge 212, and the radial dimension of the first magnetic bridge 212 is 1.05mm-1.1mm.

[0100] The radial inner end of the second cavity 21b is the end of the second cavity 21b that is radially close to the radial inner side.

[0101] The radial inner edge of the rotor core 21 is the edge line of the rotor core 21 that is closest to the axis in the radial direction.

[0102] The first magnetic bridge 212 is a solid structure located between the radial inner end and the radial inner edge of the second cavity 21b.

[0103] For example, the first magnetic bridge 212 has a radial dimension of either 1.05 mm or 1.1 mm, or a value between the two.

[0104] In this embodiment, the first magnetic bridge 212 has a radial dimension of 1.05mm-1.1mm, which reduces the leakage flux and avoids excessive magnetic flux loss, thus improving the utilization rate of the permanent magnet 221 and thereby increasing the torque output and power density of the motor. It also avoids the problem of insufficient mechanical strength caused by excessive narrowing of the first magnetic bridge 212, which helps to maintain the overall rigidity of the rotor core 21 structure, allowing the rotor core 21 to withstand the centrifugal force impact under high-speed rotation, meeting the requirements for mechanical stability in high-speed operation scenarios, reducing magnetic flux flow while meeting mechanical strength requirements, and balancing the electromagnetic performance of the motor with the structural reliability of long-term operation.

[0105] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The part of the rotor core 21 located between two adjacent second cavities 21b is the second magnetic bridge 213, and the circumferential dimension of the second magnetic bridge 213 is 1.4mm-1.7mm.

[0106] The second magnetic bridge 213 is a solid structure located between two adjacent second cavities 21b.

[0107] For example, the second magnetic bridge 213 has a circumferential dimension of any one of 1.4 mm, 1.5 mm, 1.6 mm and 1.7 mm or a value between any two of them.

[0108] In this embodiment, the second magnetic bridge 213 has a circumferential dimension of 1.4mm-1.7mm, which makes it easier for the second magnetic bridge 213 to enter the magnetic saturation state, reduce the leakage flux of the permanent magnet 221, improve the utilization rate of the permanent magnet 221, and help the motor achieve higher torque density and operating efficiency. It also helps to maintain the overall rigidity of the rotor core 21 structure, avoid problems such as insufficient local rigidity and stress concentration, and ensure that the rotor core 21 can withstand sufficient centrifugal force when rotating at high speed, thus meeting the requirements for mechanical stability in high-speed operation scenarios.

[0109] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 The part of the rotor core 21 located between the first cavity 21a and the second cavity 21b is the third magnetic bridge 214, and the circumferential dimension of the third magnetic bridge 214 is 0.95mm-1.05mm.

[0110] The third magnetic bridge 214 is a solid structure located between the first cavity 21a and the second cavity 21b.

[0111] For example, the third magnetic bridge 214 has a circumferential dimension of either 0.95 mm or 1.05 mm.

[0112] In this embodiment, the third magnetic bridge 214 has a circumferential dimension of 0.95mm-1.05mm, which makes it easier for the third magnetic bridge 214 to enter the magnetic saturation state. This prevents the permanent magnet flux from forming a fixed bypass leakage flux through the third magnetic bridge 214. When the rotor assembly 2 is stationary or at low speed, the magnetic sliding member 23 remains in the first position, the magnetic flux of the third magnetic bridge 214 is saturated, and the flow of magnetic flux through the magnetic circuit is restricted. The magnetic pole 22 is not coupled with leakage flux by the magnetic sliding member 23, ensuring that the permanent magnet flux enters the air gap as much as possible to maintain sufficient output torque under stationary or low-speed conditions. This also meets the mechanical structural strength requirements of the rotor assembly 2 at high speed, helps maintain the overall rigidity of the rotor core 21 structure, avoids problems such as insufficient local rigidity and stress concentration, and ensures that the rotor core 21 can withstand sufficient centrifugal force when rotating at high speed, meeting the mechanical stability requirements under high-speed operation scenarios. In conjunction with the magnetic sliding member 23 in the first cavity 21a, the rotational speed adaptive flux passive adjustment is achieved, improving the high-speed cruising efficiency of the motor and the overall vehicle range.

[0113] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way.

Claims

1. An electric motor, characterized in that, include: Stator assembly; The rotor assembly is sleeved on the outside of the stator assembly. The rotor assembly includes a rotor core, multiple magnetic poles, multiple magnetic sliding members, and multiple elastic reset members. A portion of the magnetic poles are N poles and another portion of the magnetic poles are S poles. The N poles and the S poles are alternately arranged on the rotor core along the circumferential direction. The magnetic pole includes two permanent magnets, with their radially outer ends close to each other and their radially inner ends far apart. The rotor core is located between the radially outer ends of the two permanent magnets to form a first cavity, and a magnetically conductive sliding member that can slide radially is provided in the first cavity. The magnetically conductive slider has a first position and a second position, the second position being radially outside the first position. The elastic force of the elastic reset member holds the magnetically conductive slider in the first position, and the centrifugal force of the rotor assembly drives the magnetically conductive slider to move to the second position against the elastic force of the elastic reset member.

2. The motor according to claim 1, characterized in that, The elastic reset member is disposed in the first cavity, and the elastic reset member is connected to the outer end of the magnetically conductive sliding member in the radial direction.

3. The motor according to claim 1, characterized in that, The rotor core forms a boss protruding into the first cavity. The boss is located radially outside the magnetically conductive sliding member and is used to limit the magnetically conductive sliding member to the second position.

4. The motor according to claim 3, characterized in that, The circumferential dimension of the boss is 0.4mm-1.2mm.

5. The motor according to claim 1, characterized in that, The first cavity is filled with a lubricating medium.

6. The motor according to claim 1, characterized in that, In the circumferential direction, the gap between the magnetically conductive sliding member and the wall of the first cavity is greater than 0 mm and less than 0.1 mm.

7. The motor according to claim 1, characterized in that, The rotor core forms multiple second cavities spaced apart along the circumference, and the permanent magnet is embedded in the second cavity.

8. The motor according to claim 7, characterized in that, The portion of the rotor core located between the radial inner end and the radial inner edge of the second cavity is the first magnetic bridge, and the radial dimension of the first magnetic bridge is 1.05mm-1.1mm.

9. The motor according to claim 7, characterized in that, The portion of the rotor core located between two adjacent second cavities is the second magnetic bridge, and the circumferential dimension of the second magnetic bridge is 1.4mm-1.7mm.

10. The motor according to claim 7, characterized in that, The portion of the rotor core located between the first cavity and the second cavity is the third magnetic bridge, and the circumferential dimension of the third magnetic bridge is 0.95mm-1.05mm.

11. The motor according to any one of claims 1 to 10, characterized in that, When the rotor assembly reaches the preset speed, the magnetic sliding member moves to the second position.

12. A vehicle, characterized in that, include: Vehicle body; The motor according to any one of claims 1 to 11, wherein the motor is disposed on the vehicle body and the motor is used to drive the vehicle body to move.

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