A stator assembly with yoke translation, electric machine, and vehicle

Abstract

This invention discloses a stator assembly for yoke translation, a motor, and a transport vehicle. The stator assembly for yoke translation includes a stator and a yoke pushing device. The stator includes a stator toothed portion, a stator coil wound around the stator toothed portion, and a movable yoke. The yoke pushing device includes an actuator and a controller connected to the actuator. The controller controls the movement of the actuator. The actuator is connected to the movable yoke and, under the control of the controller, pushes the movable yoke to move along the axial direction of the stator toothed portion, adjusting the length of the overlapping portion of the movable yoke and the stator toothed portion in the axial direction. This invention can effectively adjust the magnitude of the back electromotive force on the stator coil.

Description

Technical Field

[0001] This invention relates to a stator assembly with yoke translation, a motor, and a vehicle, belonging to the field of motor technology. Background Technology

[0002] When a motor rotates, a back electromotive force (EMF) is generated in the stator coils. The higher the rotational speed, the higher the back EMF. When the back EMF is higher than the power supply voltage, the motor cannot operate normally in drive mode.

[0003] In the design of modern motors, especially permanent magnet motors, a compromise must be made between torque and speed. While ensuring high torque in the low-speed range, current control methods such as field weakening are generally used to suppress back electromotive force in the high-speed range. However, field weakening control increases motor losses in the high-speed range. Therefore, improvements are made to the motor structure to suppress back electromotive force.

[0004] Some motors allow the rotor to move controllably relative to the stator in the axial direction. At low speeds, the rotor and stator coincide in the axial direction; at high speeds, a mechanical device forces the rotor to deviate axially, preventing complete axial overlap and thus reducing back electromotive force. Axial movement of the high-speed rotating rotor requires complex mechanical structures and is rarely used in practice. Axial movement of the stator connected to the power supply lines can impair the motor's electrical reliability and lifespan.

[0005] The Chinese patent with application number 201810534836.8 uses the method of moving the stator teeth relative to the stator yoke to reduce the difficulty of coil winding and avoid the problem of excessive magnetic voltage drop caused by excessive tooth spacing. However, the assembled motor rotor and stator cannot be moved controllably in the axial direction. When the motor rotates at high speed, the back electromotive force will increase and affect the normal operation of the motor. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a stator assembly, motor, and transport vehicle with yoke translation, which can effectively adjust the magnitude of the back electromotive force on the stator coils. To achieve the above objective, this invention employs the following technical solution:

[0007] In a first aspect, the present invention provides a stator assembly for yoke translation, comprising a stator and a yoke pushing device.

[0008] The stator includes a stator toothed portion, a stator coil wound around the stator toothed portion, and a movable yoke.

[0009] The yoke pushing device includes an actuator and a controller connected to the actuator. The controller is used to control the movement of the actuator. The actuator is connected to the movable yoke and is used to push the movable yoke to move along the axial direction of the stator tooth groove under the control of the controller, and to adjust the length of the overlapping portion of the movable yoke and the stator tooth groove in the axial direction.

[0010] In conjunction with the first aspect, optionally, a guide rail is provided axially on the outer side of the stator tooth groove to constrain the movable yoke to move along the axial direction of the stator tooth groove.

[0011] In conjunction with the first aspect, optionally, the yoke pushing device is located on the side of the movable yoke, and is in surface contact with the movable yoke or in multi-point contact along the circumference of the movable yoke.

[0012] In conjunction with the first aspect, optionally, a reset device is connected to the other side of the movable yoke, the reset device being used to restore the movable yoke to its initial position.

[0013] In conjunction with the first aspect, optionally, the movable yoke is divided into two parts along the axial direction, including a left movable yoke and a right movable yoke; the yoke pushing device is located in the middle of the left movable yoke and the right movable yoke, and is used to push the left movable yoke to move to the left along the axial direction and push the right movable yoke to move to the right along the axial direction.

[0014] In conjunction with the first aspect, optionally, a reset device is connected to the left side of the left movable yoke and the right side of the right movable yoke, respectively, and the reset device is used to restore the movable yoke to its initial position.

[0015] In conjunction with the first aspect, optionally, the stator tooth groove portion and the movable yoke portion are engaged by an alternating tooth-like structure.

[0016] In conjunction with the first aspect, optionally, it also includes a fixed yoke portion, which is disposed between the stator tooth groove portion and the movable yoke portion and is connected to the stator tooth groove portion.

[0017] In a second aspect, the present invention provides an electric motor comprising a stator assembly with a yoke translation as described in the first aspect and a rotor, wherein the stator assembly with the yoke translation is sleeved on the circumference of the rotor.

[0018] Thirdly, the present invention provides a vehicle driven by the motor described in the second aspect.

[0019] Compared with the prior art, the beneficial effects achieved by the stator assembly, motor, and vehicle for yoke translation provided in the embodiments of the present invention include:

[0020] This invention includes a stator and yoke pushing device. The yoke pushing device includes an actuator and a controller connected to the actuator. The controller controls the movement of the actuator. The actuator is connected to a movable yoke and, under the control of the controller, pushes the movable yoke to move along the axial direction of the stator toothed portion.

[0021] This invention adjusts the average magnetic induction intensity of the closed magnetic circuit formed by the rotor, stator tooth slot, and movable yoke by adjusting the length of the overlapping portion of the movable yoke and the stator tooth slot in the axial direction. This effectively adjusts the magnitude of the back electromotive force on the stator coil, thereby increasing the motor speed, reducing system energy consumption, and reducing energy consumption at high speeds.

[0022] This invention eliminates the need for a rotor that rotates at high speed with axial movement, as well as a stator that requires power to move axially. It has a simple structure and high reliability. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a stator assembly with yoke translation provided in Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of a stator assembly with yoke translation provided in Embodiment 1 of the present invention, in which the movable yoke and the stator tooth groove coincide in the axial direction.

[0025] Figure 3 This is a schematic diagram of the structure of a stator assembly with yoke translation provided in Embodiment 1 of the present invention, in which the movable yoke and the stator tooth groove do not completely overlap in the axial direction.

[0026] Figure 4 This is a schematic diagram of a reset device in a stator assembly for yoke translation provided in Embodiment 1 of the present invention;

[0027] Figure 5 This is a schematic diagram of the fit between the stator tooth groove and the movable yoke in a stator assembly with yoke translation provided in Embodiment 1 of the present invention.

[0028] Figure 6 This is a schematic diagram of a yoke pushing device in a stator assembly for yoke translation provided in Embodiment 2 of the present invention;

[0029] Figure 7 This is a schematic diagram of the yoke portion in a stator assembly with yoke translation provided in Embodiment 3 of the present invention.

[0030] In the picture:

[0031] 1. Reset device; 2. Movable yoke; 3. Stator toothed section; 4. Stator coil;

[0032] 5. Yoke driving device; 6. Motor air gap;

[0033] 7. The fixed yoke;

[0034] 8. Rotor. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] In the description of this invention, it should be noted that the terms "upper / lower end," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0037] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "set / sleeved," "sleeved," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Example 1

[0038] like Figure 1 As shown, this embodiment provides a stator assembly for yoke translation, including a stator and a yoke pushing device 5. The stator includes a stator toothed portion 3, a stator coil 4 wound around the stator toothed portion 3, and a movable yoke 2. A motor air gap 6 is provided between the stator toothed portion 3 and the rotor 8. In this embodiment, the motor air gap 6 is a fixed value.

[0039] The yoke pushing device 5 includes an actuator and a controller connected to the actuator. The controller is used to control the movement of the actuator, which is connected to the movable yoke 2 and is used to push the movable yoke 2 along the axial direction of the stator tooth groove 3 under the control of the controller.

[0040] like Figure 2As shown, when the motor is stationary or at low speed, the back electromotive force generated by the rotation of the motor rotor is lower than the driving voltage applied to the stator coils. Under the control of the controller, the actuator of the yoke pushing device 5 makes the movable yoke 2 and the stator toothed part 3 coincide in the axial direction. At this time, the average magnetic induction intensity of the closed magnetic circuit formed by the rotor 8, the stator toothed part 3 and the movable yoke 2 is relatively large, which is conducive to generating large torque and high back electromotive force.

[0041] like Figure 3 As shown, when the motor is at high speed, if the back electromotive force generated by the rotor rotation is higher than the driving voltage or preset voltage applied to the stator coils, the actuator of the yoke pushing device 5, under the control of the controller, pushes the movable yoke 2 along the axial direction of the stator toothed portion 3, causing the movable yoke 2 and the stator toothed portion 3 to not completely overlap in the axial direction. At this time, the movable yoke 2 and the stator toothed portion 3 tend to be magnetically saturated in the non-overlapping area, and the average magnetic induction intensity of the closed magnetic circuit formed by the rotor 8, the stator toothed portion 3, and the movable yoke 2 decreases, thereby suppressing the rise of the back electromotive force in the coils. The higher the back electromotive force generated by the rotor rotation is compared to the driving voltage or preset voltage applied to the stator coils, the greater the length of the non-overlapping length between the movable yoke 2 and the stator toothed portion 3 in the axial direction.

[0042] By adjusting the length of the overlapping portion of the movable yoke 2 and the stator toothed portion 3 in the axial direction, the average magnetic induction intensity of the closed magnetic circuit formed by the rotor 8, the stator toothed portion 3 and the movable yoke 2 can be adjusted, thereby effectively adjusting the magnitude of the back electromotive force on the stator coil 4.

[0043] Specifically, a motor is in a low-speed state when its speed does not exceed 50% of its rated speed, and a motor is in a high-speed state when its speed exceeds 50% of its rated speed.

[0044] Specifically, a guide rail is provided axially on the outer side of the stator tooth groove 3 to constrain the movable yoke 2 to move along the axial direction of the stator tooth groove 3. Without the guide rail, the movable yoke 2 would be difficult to translate and slide.

[0045] In this embodiment, the yoke pushing device 5 is located on the side of the movable yoke 2, and is in contact with the surface of the movable yoke 2 or in multiple points along the circumference of the movable yoke 2, so as to prevent the movable yoke 2 from getting stuck on the guide rail.

[0046] like Figure 4 As shown, a reset device 1 is connected to the other side of the movable yoke 2. The reset device 1 is used to restore the movable yoke 2 to its initial position.

[0047] Specifically, the reset device 1 is an elastic device such as a spring, a hydraulic device, or a pneumatic device.

[0048] like Figure 5 As shown, the stator tooth groove 3 and the movable yoke 2 are engaged by an alternating tooth structure, which ensures that the movable yoke 2 and the stator tooth groove 3 achieve better magnetic circuit performance and mechanical performance. Example 2

[0049] like Figure 6 As shown, this embodiment provides a stator assembly for yoke translation, including a stator and a yoke pushing device 5. The stator includes a stator toothed portion 3, a stator coil 4 wound around the stator toothed portion 3, and a movable yoke 2. A motor air gap 6 is provided between the stator toothed portion 3 and the rotor 8. In this embodiment, the motor air gap 6 is a fixed value.

[0050] The yoke pushing device 5 includes an actuator and a controller connected to the actuator. The controller is used to control the movement of the actuator, which is connected to the movable yoke 2 and is used to push the movable yoke 2 along the axial direction of the stator tooth groove 3 under the control of the controller.

[0051] Similar to the stator tooth groove 3 in Embodiment 1, the stator tooth groove 3 in this embodiment is provided with a guide rail on its outer side in the axial direction to constrain the movable yoke 2 to move along the axial direction of the stator tooth groove 3. Without the guide rail, the movable yoke 2 would be difficult to translate and slide.

[0052] In this embodiment, as Figure 6 As shown, the movable yoke 2 is divided into two parts along the axial direction, including a left movable yoke 2 and a right movable yoke 2. The yoke pushing device 5 is located between the left movable yoke 2 and the right movable yoke 2. When the motor is at high speed, the yoke pushing device 5 pushes the left movable yoke 2 to move to the left along the axial direction and pushes the right movable yoke 2 to move to the right along the axial direction, so that the movable yoke 2 and the stator tooth groove 3 do not completely overlap in the axial direction.

[0053] By adjusting the length of the overlapping portion of the movable yoke 2 and the stator toothed portion 3 in the axial direction, the average magnetic induction intensity of the closed magnetic circuit formed by the rotor 8, the stator toothed portion 3 and the movable yoke 2 can be adjusted, thereby effectively adjusting the magnitude of the back electromotive force on the stator coil 4.

[0054] The yoke pushing device 5 pushes the two parts of the movable yoke 2 in opposite directions, which can effectively utilize the space of the stator tooth groove 3 coil.

[0055] In this embodiment, a reset device 1 is connected to the left side of the left movable yoke 2, which is used to push the left movable yoke 2 to the right to restore it to its initial position. A reset device 1 is connected to the right side of the right movable yoke 2, which is used to push the right movable yoke 2 to the left to restore it to its initial position.

[0056] Specifically, the reset device 1 is an elastic device such as a spring, a hydraulic device, or a pneumatic device.

[0057] The stator tooth groove 3 and the movable yoke 2 are connected by means of... Figure 5 The interlocking tooth-like structures shown can be matched to ensure that the movable yoke 2 and the stator tooth groove 3 achieve better magnetic circuit performance and mechanical performance. Example 3

[0058] like Figure 7 As shown, this embodiment provides a stator assembly with yoke translation, including a stator and a yoke pushing device 5. The stator includes a stator toothed portion 3, a stator coil 4 wound around the stator toothed portion 3, and a movable yoke 2. In this embodiment, a fixed yoke 7 is also included, which is disposed between the stator toothed portion 3 and the movable yoke 2 and connected to the stator toothed portion 3. The fixed yoke 7 is used to fix the fixed toothed portion 3, which has the advantages of easy manufacturing and enhanced mechanical strength.

[0059] In this embodiment, a guide rail is provided on the outer side of the stator tooth groove portion 3 to constrain the movement of the fixed yoke portion 7 along the axial direction of the stator tooth groove portion 3. Without the guide rail, the movable yoke portion 2 would be difficult to translate and slide.

[0060] A motor air gap 6 is provided between the stator tooth groove 3 and the rotor 8. In this embodiment, the motor air gap 6 is a fixed value.

[0061] The yoke pushing device 5 includes an actuator and a controller connected to the actuator. The controller controls the movement of the actuator, which is connected to the movable yoke 2 and is used to push the movable yoke 2 along the axial direction of the stator tooth groove 3 under the control of the controller. Figure 7 In the paper, the movable yoke 2 moves in a direction perpendicular to the plane of the paper.

[0062] By adjusting the length of the overlapping portion of the movable yoke 2 and the stator toothed portion 3 in the axial direction, the average magnetic induction intensity of the closed magnetic circuit formed by the rotor 8, the stator toothed portion 3 and the movable yoke 2 can be adjusted, thereby effectively adjusting the magnitude of the back electromotive force on the stator coil 4.

[0063] In this embodiment, the yoke pushing device 5 can push the movable yoke 2 to one side as described in Embodiment 1, or it can push the two movable yoke parts 2 in opposite directions as described in Embodiment 2.

[0064] The movable yoke 2 is connected to a reset device 1 on its side for returning the movable yoke 2 to its initial position. Specifically, the reset device 1 is an elastic device such as a spring, a hydraulic device, or a pneumatic device.

[0065] like Figure 5As shown, the stator tooth groove 3 and the movable yoke 2 are engaged by an alternating tooth structure, which ensures that the movable yoke 2 and the stator tooth groove 3 achieve better magnetic circuit performance and mechanical performance. Example 4

[0066] This embodiment provides an electric motor, including a stator assembly with yoke translation as described in any one of Embodiment 1, Embodiment 2, and Embodiment 3, and a rotor 8, wherein the stator assembly with yoke translation is sleeved on the circumference of the rotor 8.

[0067] The stator assembly with yoke translation described in any one of Embodiments 1, 2, and 3 is applicable to both internal rotor motors and external rotor motors.

[0068] The motor provided in this embodiment can be an internal rotor motor or an external rotor motor. Example 5

[0069] This embodiment provides a vehicle that is driven by the motor described in Embodiment 4.

[0070] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0071] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0072] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A yoke translated stator assembly characterized by, Includes stator and yoke driving mechanism, The stator includes a stator toothed portion, a stator coil wound around the stator toothed portion, a movable yoke, and a fixed yoke; The fixed yoke is located between the stator tooth groove and the movable yoke, and is connected to the stator tooth groove; The movable yoke is divided into two parts along the axial direction, including a left movable yoke and a right movable yoke; the yoke pushing device is located in the middle of the left movable yoke and the right movable yoke, and is used to push the left movable yoke to move to the left along the axial direction and push the right movable yoke to move to the right along the axial direction; a reset device is connected to the left side of the left movable yoke and the right side of the right movable yoke, respectively, and the reset device is used to restore the movable yoke to its initial position; The stator tooth groove is provided with an axial guide rail on the outer side to constrain the movable yoke to move along the axial direction of the stator tooth groove. The stator toothed portion and the movable yoke portion are engaged by an alternating tooth-like structure; By adjusting the length of the overlapping portion of the movable yoke and the stator slotted portion in the axial direction, the average magnetic induction intensity of the closed magnetic circuit formed by the rotor, the stator slotted portion and the movable yoke is adjusted, thereby adjusting the magnitude of the back electromotive force on the stator coil.

2. The yoke translated stator assembly of claim 1, wherein, The yoke pushing device includes an actuator and a controller connected to the actuator. The controller is used to control the movement of the actuator. The actuator is connected to the movable yoke and is used to push the movable yoke to move along the axial direction of the stator tooth groove under the control of the controller, and to adjust the length of the overlapping portion of the movable yoke and the stator tooth groove in the axial direction.

3. The yoke translated stator assembly of claim 1 wherein, The yoke pushing device is located on the side of the movable yoke, and is in contact with the surface of the movable yoke or in multiple points along the circumference of the movable yoke; a reset device is connected to the other side of the movable yoke, and the reset device is used to restore the movable yoke to its initial position.

4. An electric machine characterized by The stator assembly with yoke translation as described in any one of claims 1-3 and the rotor are included, wherein the stator assembly with yoke translation is sleeved on the circumference of the rotor.

5. A vehicle characterized by, It is driven by the motor described in claim 4.

Images