Stator capable of reducing cogging torque

Abstract

The utility model discloses a stator capable of reducing cogging torque, which comprises a stator body and stator teeth arranged on the stator body, the tooth part of each stator tooth forms a rotor hole along the circumferential direction, a stator tooth slot is formed between two adjacent stator teeth, and the stator tooth slot is provided with a stator notch. According to the utility model, the distribution of stator magnetic conductance can be changed, so that the stator magnetic conductance waveform is closer to a sine wave, thereby reducing the content and amplitude of magnetic conductance harmonic waves, optimizing the magnetic conductance of a magnetic circuit, and achieving the purpose of reducing cogging torque.

Description

Technical Field

[0001] The utility model relates to the technical field of stator sheets, and particularly relates to a stator for reducing cogging torque. Background Art

[0002] Due to advantages such as simple structure, high efficiency, large power density, and high torque density, permanent magnet synchronous motors are widely used in the fields of rail transit, aerospace, wind power generation, and household appliances. As one of the most important parameters of permanent magnet synchronous motors, cogging torque has an important impact on the application of permanent magnet synchronous motor products in these fields. Cogging torque is caused by the physical structure of the permanent magnet synchronous motor itself. There is a tangential force acting on each other between the side with permanent magnets and the side with slots in the stator and rotor. The torque generated by this acting force has a tendency to keep the teeth and slots and the magnetic poles of the permanent magnets aligned. Even when there is no current in the stator winding, this torque still exists. Excessive cogging torque will cause torque fluctuations, vibrations, and noises in the generator, affecting the normal use of the generator.

[0003] In the existing stator punching structure, due to the influence of stator slotting, the stator magnetic conductance is unevenly distributed along the air gap, forming stator teeth with larger magnetic conductance and stator slot openings with smaller magnetic conductance. Due to the principle of minimum magnetic resistance, the magnetic resistance on the magnetic circuit corresponding to the permanent magnet is unbalanced, thus pulling the rotor to the position with the minimum magnetic resistance and generating cogging torque. Due to the existence of cogging torque, torque pulsation will occur when the motor rotates, thus affecting the control accuracy and speed fluctuation. At the same time, torque pulsation will also cause vibrations and noises, thus affecting the positioning accuracy and servo performance of the motor.

[0004] Therefore, how to solve the deficiencies existing in the above-mentioned prior art has become the subject to be studied and solved in this application. Content of the Utility Model

[0005] In view of this, the purpose of the utility model is to provide a stator for reducing cogging torque.

[0006] To achieve the above purpose, the technical scheme adopted by the utility model is:

[0007] A stator for reducing cogging torque includes a stator body and stator teeth provided on the stator body. The tooth parts of each stator tooth form a rotor hole along the circumferential direction. A stator tooth slot is formed between two adjacent stator teeth, and a stator slot opening is provided on the stator tooth slot.

[0008] Further, the tooth part of the stator tooth is a T-shaped structure protruding towards the center of the stator body. The protruding midpoints of the tooth parts of each stator tooth are connected to form the rotor hole, and the tooth parts of the stator teeth are shaped at the protruding midpoints of the tooth parts of each stator tooth.

[0009] Further, the peak-to-peak value of the cogging torque is 325 mNm.

[0010] Further, the tooth part of the stator tooth is a T-shaped structure sunken towards the center of the stator body. The midpoints of the depressions of the tooth parts of the stator teeth are connected to form the rotor hole. The tooth parts of the stator teeth are shaped at the midpoints of the depressions of the tooth parts, and the rotor hole is enlarged to reduce the cogging torque.

[0011] Further, the peak-to-peak value of the cogging torque is 213 mNm.

[0012] Further, the tooth part of the stator tooth is T-shaped. The tooth parts of three adjacent stator teeth are arranged in a group, and the tooth parts of each group of stator teeth form the rotor hole along the circumferential direction.

[0013] Further, the peak-to-peak value of the cogging torque is 252 mNm.

[0014] Further, the distance between the two side walls of the stator tooth groove gradually increases from the stator slot opening to the slot bottom.

[0015] Compared with the prior art, the advantages of the present utility model are as follows: By shaping the tooth part of the stator tooth, the permeance of the tooth part of the stator tooth is optimized, thereby reducing the cogging torque of the motor, further reducing the torque ripple, and improving the running stability and control accuracy of the motor. This application can change the distribution of the stator permeance, making the stator permeance waveform closer to a sine wave, thereby reducing the content and amplitude of the permeance harmonics, optimizing the permeance of the magnetic circuit, and achieving the purpose of reducing the cogging torque. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Attached Figure 1 is a schematic structural diagram of Embodiment 1 of this application;

[0018] Attached Figure 2 is a schematic structural diagram of Embodiment 2 of this application;

[0019] Attached Figure 3 is a schematic structural diagram of Embodiment 3 of this application.

[0020] Explanation of the reference numerals and components involved in the drawings:

[0021] 1. Stator body; 2. Stator tooth; 3. Stator slot opening; 4. Rotor hole. Detailed Embodiments

[0022] The technical solution of the present utility model will be clearly and completely described below through specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0023] The motor stator is an important part of motors such as generators and starters. The stator is an important part of the motor. The stator is composed of a stator core, a stator winding, and a frame. The main function of the stator is to generate a rotating magnetic field, while the main function of the rotor is to be cut by magnetic lines of force in the rotating magnetic field to generate current. The stator winding includes stator laminations and coils wound around the stator laminations. See the attached Figures 1 - 3 As shown, a stator for reducing cogging torque in the present application includes a stator body 1 and stator teeth 2 provided on the stator body 1. The tooth portions of the stator teeth 2 form a rotor hole 4 along the circumferential direction. A stator tooth slot is formed between two adjacent stator teeth 2, and a stator slot opening 3 is provided on the stator tooth slot. In the present application, the stator teeth 2 are shaped, and the tooth portions of the stator teeth 2 are shaped to optimize the magnetic conductance of the tooth portions of the stator teeth 2, thereby reducing the cogging torque of the motor, further reducing torque ripple, and improving the running stability and control accuracy of the motor.

[0024] Embodiment 1:

[0025] See the attached Figure 1 As shown, the tooth portion of the stator tooth 2 is a T-shaped structure protruding towards the center of the stator body 1. The protruding midpoints of the tooth portions of the stator teeth 2 are connected to form a rotor hole 4, and the tooth portions of the stator teeth 2 are shaped at the protruding midpoints of the tooth portions of the stator teeth 2. The tooth portions of the stator teeth 2 in the present application are not distributed along the circumference of the inner diameter of the stator body 1. Taking the protruding center point of the tooth portion of the stator tooth 2 as the vertex of the arc, the tooth portion of the stator tooth 2 is shaped towards the outer diameter direction, so that the tooth portion of the stator tooth 2 is T-shaped. This structure can change the distribution of the stator magnetic conductance, make the stator magnetic conductance waveform closer to a sine wave, thereby reducing the content and amplitude of the magnetic conductance harmonics, optimizing the magnetic conductance of the magnetic circuit, and achieving the purpose of reducing the cogging torque.

[0026] Embodiment 2:

[0027] See the attached Figure 2 As shown, the tooth portion of the stator tooth 2 is a T-shaped structure recessed towards the center of the stator body 1. The recessed midpoints of the tooth portions of the stator teeth 2 are connected to form a rotor hole 4, and the tooth portions of the stator teeth 2 are shaped at the recessed midpoints of the tooth portions of the stator teeth 2. The rotor hole 4 is enlarged to reduce the cogging torque. The tooth portions of the stator teeth 2 in the present application are not distributed along the circumference of the inner diameter of the stator body 1. The stator teeth 2 are shaped along the inner diameter direction, so that the air gap in the central part of the stator teeth 2 is increased, thereby optimizing the magnetic conductance of the stator tooth portion and achieving the purpose of reducing the cogging torque.

[0028] Embodiment 3:

[0029] See the appendix Figure 3 As shown, the tooth part of the stator tooth 2 is in a T shape. The tooth parts of three adjacent stator teeth 2 are arranged in a group, and the tooth parts of each group of stator teeth 2 form a rotor hole 4 along the circumference. The tooth part of the stator tooth 2 in this application is not distributed along the circumference of the inner diameter of the stator body 1. The stator tooth 2 is modified so that the stator tooth 2 is arranged in three Ts, thereby optimizing the permeance waveform, making the permeance waveform more sinusoidal and reducing the cogging torque.

[0030] In this application, the tooth part of the stator tooth 2 is modified to optimize the permeance of the tooth part of the stator tooth 2, thereby reducing the cogging torque of the motor, further reducing the torque ripple, and improving the running stability and control accuracy of the motor.

[0031] The peak-to-peak value of the cogging torque in the existing design is 551 mNm, the peak-to-peak value of the cogging torque in Embodiment 1 is 325 mNm, and the cogging torque is reduced by 49%. The peak-to-peak value of the cogging torque in Embodiment 2 is 213 mNm, and the cogging torque is reduced by 61.3%. The peak-to-peak value of the cogging torque in Embodiment 3 is 252 mNm, and the cogging torque is reduced by 54.2%.

[0032] Preferably, see the appendix Figures 1 - 3 As shown, the distance between the two side walls of the stator tooth groove in this embodiment gradually increases from the stator slot opening 3 to the slot bottom.

[0033] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A stator for reducing cogging torque, characterized in that, It includes a stator body and stator teeth provided on the stator body. The tooth parts of the stator teeth form a rotor hole in the circumferential direction. A stator tooth slot is formed between two adjacent stator teeth, and a stator slot opening is provided on the stator tooth slot. The tooth part of the stator tooth is a T-shaped structure. The T-shaped structure includes a first form protruding towards the center of the stator body and a second form recessed towards the center of the stator body. The protruding midpoints or recessed midpoints of the tooth parts of the stator teeth are connected to form the rotor hole, and the tooth parts of the stator teeth are shaped at the protruding midpoints or recessed midpoints of the tooth parts of the stator teeth.

2. The stator for reducing cogging torque according to claim 1, wherein When the tooth part of the stator tooth is in the protruding first form, the peak-to-peak value of the cogging torque is 325 mNm.

3. The stator for reducing cogging torque according to claim 1, wherein When the tooth part of the stator tooth is in the recessed second form, the peak-to-peak value of the cogging torque is 213 mNm.

4. The stator for reducing cogging torque according to claim 1, wherein The tooth parts of three adjacent stator teeth are arranged in a group, and the tooth parts of each group of stator teeth form the rotor hole in the circumferential direction.

5. The stator for reducing cogging torque according to claim 4, characterized in that, The peak-to-peak value of the cogging torque is 252 mNm.

6. The stator for reducing cogging torque according to claim 1, wherein The distance between the two side walls of the stator tooth slot gradually increases from the stator slot opening to the slot bottom.

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