CN116345831A - Bearingless switch reluctance motor with tooth-shaped structure - Google Patents

Abstract

The invention relates to a toothed structure bearingless switched reluctance motor, comprising: a doubly salient pole stator and rotor, a doubly salient pole stator and rotor including a rotor, and a stator sheathed on the periphery of the rotor; Corresponding stator teeth; the rotor is provided with several sets of rotor teeth extending outward; the stator teeth are wound with several sets of stator windings; the inner side of the stator teeth is provided with internal auxiliary slots for the stator teeth; the rotor teeth are provided with Auxiliary slots inside the rotor tooth poles. The invention provides a bearingless switched reluctance motor with a tooth structure, which can increase the reluctance and change the distribution of the magnetic field lines inside the motor, thereby weakening the radial flux density in the air gap, increasing the tangential flux density, and finally achieving an increase The average torque, the purpose of greatly reducing the torque ripple, is conducive to improving the performance of the bearingless switched reluctance motor.

Description

Bearingless Switched Reluctance Motor with Toothed Structure

technical field

The invention relates to the mechanical field, in particular to a toothed structure bearingless switched reluctance motor.

Background technique

In the prior art, for example, the existing patent, patent number: CN202110629280.2, patent name: a new type of switched reluctance motor with stator and rotor tooth structure; a new type of switched reluctance motor with stator and rotor tooth structure disclosed , including the stator, rotor, shaft, stator arc teeth, rotor auxiliary slots and rotor vents. The rotor is embedded in the stator, the rotor is coaxial with the stator, the rotating shaft is set at the center of the rotor, and the arc tooth structure of the stator is an inward arc on both sides of the stator teeth Shaped structure, the auxiliary rotor slots are rectangular slots on both sides of the rotor teeth, and the rotor vents are arranged on the rotor.

Due to the unique double salient pole structure of the switched reluctance motor and the switching power supply mode, the saturation degree of the salient poles of the stator and rotor is high during the operation of the motor, the effect of the edge flux is obvious, and the magnetic circuit is highly saturated, and the magnetic circuit characteristics are relatively Compared with other motors, it is more complicated, and the parameters such as current and magnetic flux show nonlinear changes, and its torque ripple is more obvious than other motors. At the same time, the electromagnetic torque of the switched reluctance motor is synthesized by the torque of two adjacent phases. The switching power supply mode and the non-linear change of the current caused by the high saturation of the magnetic circuit also cause the motor to lose its power during commutation. Torque ripple.

Although the three-phase 12/8-pole bearingless switched reluctance motor is a special switched reluctance motor, the double salient pole structure and switching power supply mode of the motor have not changed, so the problem of large torque ripple still exists. It hinders the further development of the bearingless switched reluctance motor.

Contents of the invention

The present invention overcomes the deficiencies of the prior art, and provides a bearingless switched reluctance motor with a toothed structure, which can increase the reluctance and change the distribution of magnetic force lines inside the motor, thereby weakening the radial flux density in the air gap and increasing the shear resistance. The magnetic flux density can be increased to achieve the purpose of increasing the average torque and greatly reducing the torque ripple, which is conducive to improving the performance of the bearingless switched reluctance motor.

In order to achieve the above object, the technical solution adopted by the present invention is: a bearingless switched reluctance motor with a tooth structure, including: a doubly salient pole stator rotor, a doubly salient pole stator rotor including a rotor, and a stator sheathed on the periphery of the rotor ; The stator is provided with several sets of stator teeth corresponding to the rotor; the rotor is provided with several sets of rotor teeth extending outward; the stator teeth are wound with several sets of stator windings; Auxiliary slots; the rotor teeth of the rotor are provided with internal auxiliary slots of the rotor teeth.

In a preferred embodiment of the present invention, the auxiliary grooves inside the rotor tooth poles are parallelogram auxiliary grooves.

In a preferred embodiment of the present invention, the internal auxiliary grooves of the stator tooth poles are square auxiliary grooves.

In a preferred embodiment of the present invention, the counterclockwise direction is the rotor rotation direction when the motor is running; the stator tooth edge is the stator tooth edge in the contact direction between the stator teeth and the rotor teeth when the motor rotor rotates; the inside of the stator tooth pole The side length of the auxiliary slot is 3.03%-15.15% of the stator pole width, the distance from the stator tooth edge is 1.51%-15.1% of the stator pole width, and the distance from the stator tooth top is 1.21%-6.05% of the stator pole width %.

In a preferred embodiment of the present invention, the counterclockwise direction is the rotor rotation direction when the motor is running; the rotor tooth edge is the rotor tooth edge in the contact direction between the stator teeth and the rotor teeth when the motor rotor rotates; the inside of the rotor tooth pole The side length of the auxiliary groove is 14.3%-28.6% of the maximum rotor width, the height is 7.75%-10.85% of the rotor pole width, and the distance from the rotor tooth edge is 1.16%-3.48% of the rotor pole width. The distance of the top is 1.43%-5.73% of the maximum value of the rotor.

In a preferred embodiment of the present invention, it is suitable for a three-phase 12/8-pole switched reluctance motor or a three-phase 12/8-pole bearingless switched reluctance motor; the stator adopts 12 sets of stator windings.

In a preferred embodiment of the present invention, the torque ripple coefficient is: (T1-T2)/T3=0.73; wherein, T1 is the maximum torque value when the motor runs stably, and T2 is the minimum torque value when the motor runs stably , T3 is the average torque value when the motor runs stably, and the torque ripple coefficient is 0.73.

In a preferred embodiment of the present invention, the internal auxiliary grooves of the rotor tooth poles are arranged on the tooth ends of the rotor teeth on the side where the rotor teeth and the stator teeth preferentially contact; the internal auxiliary grooves of the stator tooth poles are arranged on the stator teeth and the rotor teeth On the tooth ends of the stator teeth on the side that is preferentially in contact.

In a preferred embodiment of the present invention, a method for changing the average torque of a motor, using a tooth-shaped structure of a bearingless switched reluctance motor, includes the following content: the average torque of the motor is enhanced by changing the structure of the motor stator and rotor Torque, greatly reducing the torque ripple of the motor.

There are parallelogram auxiliary slots inside the rotor teeth, and square auxiliary slots inside the stator teeth, which can increase the reluctance in the magnetic circuit and change the direction of the magnetic force lines, thereby weakening the radial magnetic density in the air gap and increasing the tangential magnetic density. Increase the average torque and greatly reduce torque ripple.

The magnetic flux always closes along the path with the least reluctance. Parallelogram auxiliary slots are set inside the rotor tooth poles, which can increase the reluctance in the magnetic circuit and change the direction of the magnetic force lines so that the magnetic force lines pass through the parallelogram auxiliary slots and the rotor tooth tops. The magnetic circuit between them enters the rotor, thereby changing the angle at which the magnetic flux enters the rotor teeth, reducing the radial magnetic density in the air gap and increasing the tangential magnetic density, increasing the average torque and reducing the inherent torque pulsation.

A square auxiliary slot is set inside the tooth pole of the stator tooth, which increases the reluctance in the magnetic circuit and changes the direction of the magnetic force line, so that when the magnetic force line passes through the square auxiliary slot and the motor rotor rotates, the stator tooth tooth edge in the contact direction of the stator and rotor teeth The magnetic circuit between the stator and rotor teeth, so that part of the magnetic field lines are squeezed, and enter the rotor teeth through the non-overlapping area of the stator and rotor teeth; The radial component is an ineffective component, and the tangential force is generated at the edge of the two overlapping areas, then the tangential component of this part is an effective component, and finally the torque ripple can be further reduced.

The present invention solves the defective that exists in the background technology, the beneficial effect of the present invention:

The invention provides a novel tooth structure, which can increase the average torque and greatly reduce the torque ripple of the motor, thereby improving the performance of the motor. The parallelogram auxiliary slots inside the rotor teeth can weaken the radial magnetic density in the air gap and increase the tangential magnetic density, thereby increasing the torque and reducing the torque ripple of the motor. The opening of square auxiliary slots inside the stator teeth can increase the reluctance, change the direction of the magnetic force lines on the stator teeth, optimize the air gap magnetic density waveform, further reduce the torque ripple of the motor, and help improve the performance of the motor.

Description of drawings

Fig. 1 is a schematic structural view of a bearingless switched reluctance motor with wide rotor teeth of a novel tooth structure in a preferred embodiment of the present invention;

Fig. 2 is a schematic structural view of the stator teeth of a bearingless switched reluctance motor with wide rotor teeth of a novel tooth structure according to a preferred embodiment of the present invention;

Fig. 3 is a schematic structural view of the rotor teeth of a bearingless switched reluctance motor with wide rotor teeth of a novel tooth shape structure according to a preferred embodiment of the present invention;

Fig. 4 is a schematic diagram of the simulation results of torque comparison between a wide rotor tooth bearingless switched reluctance motor with a new tooth shape structure of the present invention and a traditional wide rotor tooth bearingless switched reluctance motor;

Fig. 5 is the prototype dimension parameter of the wide rotor tooth bearingless switched reluctance motor of a kind of novel tooth shape structure of the present invention;

Fig. 6 is the radial magnetic density comparison diagram of the original model and the improved model;

Figure 7 shows that the maximum tangential magnetic density of the original model is 0.31T, and the maximum tangential magnetic density of the improved model is 0.43T, an increase of 38.7%;

Fig. 8 is a schematic diagram of the direction of the magnetic field lines of the original model;

Fig. 9 is a schematic diagram of the direction of the magnetic force lines of the improved model;

Figure 10 is a simulation diagram of the direction of the original model magnetic lines of force;

Fig. 11 is the simulation diagram of improving the direction of the model magnetic field line;

Figure 12 is a schematic diagram of the state of the average torque of the motor when the side length of the parallelogram auxiliary groove inside the rotor tooth pole is in the range of 1-2mm;

Figure 13 is a schematic diagram of the state of the motor torque ripple when the side length of the parallelogram auxiliary groove inside the rotor tooth pole is in the range of 1-2mm;

Figure 14 is a schematic diagram of the state of the average torque of the motor when the height of the parallelogram auxiliary groove inside the rotor tooth pole is in the range of 1-1.4mm;

Fig. 15 is a schematic diagram of the state of motor torque ripple when the height of the parallelogram auxiliary groove inside the rotor tooth pole ranges from 1 to 1.4 mm;

Figure 16 is a schematic diagram of the state of influence on the average torque of the motor when the distance between the parallelogram auxiliary slot inside the rotor tooth pole and the rotor tooth edge is 0.15-0.45 mm;

Fig. 17 is a schematic diagram of the influence on the torque ripple of the motor when the distance between the parallelogram auxiliary slot inside the rotor tooth pole and the rotor tooth edge is 0.15-0.45mm;

Figure 18 is a schematic diagram of the state of influence on the average torque of the motor when the distance between the parallelogram auxiliary slot inside the rotor tooth pole and the rotor tooth top is 0.1-0.4mm;

Fig. 19 is a schematic diagram of the influence on the torque ripple of the motor when the distance between the parallelogram auxiliary slot inside the rotor tooth pole and the rotor tooth top is 0.1-0.4mm;

Fig. 20 is a schematic diagram of the state of influence on the average torque of the motor when the side length of the square auxiliary slot inside the stator tooth pole ranges from 0.2 to 1 mm;

Fig. 21 is a schematic diagram of the influence on the torque ripple of the motor when the side length of the square auxiliary slot inside the stator tooth pole ranges from 0.2 to 1 mm;

Figure 22 is a schematic diagram of the state of the influence of the square auxiliary slot inside the stator tooth pole to the tooth edge of the stator tooth in the range of 0.1-1 mm, which affects the average torque of the motor;

Fig. 23 is a schematic diagram of the influence on the torque ripple of the motor when the distance between the square auxiliary slot inside the stator tooth pole and the tooth edge of the stator tooth is in the range of 0.1-1 mm;

Figure 24 is a schematic diagram of the state of influence on the average torque of the motor when the distance between the square auxiliary slot inside the stator tooth pole and the tooth top of the stator tooth is in the range of 0.2-1 mm;

Fig. 25 is a schematic diagram of the influence on the torque ripple of the motor when the distance between the square auxiliary slot inside the stator tooth pole and the tooth top of the stator tooth is in the range of 0.2-1 mm;

Among them, 1-stator; 2-rotor; 3-stator winding; 4-stator tooth; 5-rotor tooth; 6-square auxiliary slot; 7-parallelogram auxiliary slot; 8-stator tooth edge; 9-rotor tooth side.

Implementation

The present invention will now be further described in detail in conjunction with the accompanying drawings and embodiments. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so it only shows the composition related to the present invention.

Example

As shown in Figures 1-25, a bearingless switched reluctance motor with a toothed structure includes: a doubly salient pole stator and rotor, including a rotor 2, and a stator 1 and 12 sets of stator windings 3 sleeved on the periphery of the rotor 2 . Both the stator 1 and the rotor 2 are salient pole structures. The stator 1 is provided with several sets of stator teeth 4 correspondingly extending toward the rotor 2 ; the rotor 2 is provided with several sets of rotor teeth 5 extending outward; the stator teeth 4 are provided with several sets of stator windings 3 .

The inner side of the stator teeth 4 is provided with internal auxiliary grooves of the stator tooth poles; the internal auxiliary grooves of the stator tooth poles are square auxiliary grooves 6 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the rotor tooth edge 9 is the tooth edge of the rotor tooth 5 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary groove of the rotor tooth pole The side length is 14.3%-28.6% of the pole width of the rotor 2, the height is 7.75%-10.85% of the pole width of the rotor 2, and the distance from the tooth edge 9 of the rotor is 1.16%-3.48% of the pole width of the rotor 2. The distance between the 5 tooth tops is 1.43%-5.73% of the highest value of the rotor 2.

The rotor teeth 5 of the rotor 2 are provided with internal auxiliary grooves of the rotor teeth. The auxiliary slots inside the rotor tooth poles are parallelogram auxiliary slots 7 . Specifically, one side of the parallelogram is parallel to the sides of the rotor teeth 5 , and the other side corresponds to the top curvature of the rotor teeth 5 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the stator tooth edge 8 is the tooth edge of the stator tooth 4 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary slot of the stator tooth pole The side length is 3.03%-15.15% of the pole width of stator 1, the distance from stator tooth edge 8 is 1.51%-15.1% of the pole width of stator 1, and the distance from the top of stator tooth 4 is 1.21% of the pole width of stator 1 -6.05%.

Specifically, the torque ripple coefficient is (T1-T2)/T3=0.73; among them, T1 is the maximum torque value when the motor is running stably, T2 is the minimum torque value when the motor is running stably, and T3 is the value when the motor is running stably average torque value.

The internal auxiliary groove of the rotor tooth pole is set on the tooth end of the rotor tooth 5 on the side where the rotor tooth 5 and the stator tooth 4 preferentially contact; On the tooth end of the stator tooth 4 on the side.

Example

As shown in Figures 1-25, a bearingless switched reluctance motor with a toothed structure includes: a doubly salient pole stator and rotor 2, including a rotor 2, a stator 1 and 12 sets of stator windings sleeved on the periphery of the rotor 2 3. Both the stator 1 and the rotor 2 are salient pole structures. The stator 1 is provided with several sets of stator teeth 4 correspondingly extending toward the rotor 2 ; the rotor 2 is provided with several sets of rotor teeth 5 extending outward; the stator teeth 4 are provided with several sets of stator windings 3 .

The inner side of the stator teeth 4 is provided with internal auxiliary grooves of the stator tooth poles; the internal auxiliary grooves of the stator tooth poles are square auxiliary grooves 6 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the rotor tooth edge 9 is the tooth edge of the rotor tooth 5 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary groove of the rotor tooth pole The side length is 14.3%-28.6% of the pole width of the rotor 2, the height is 7.75%-10.85% of the pole width of the rotor 2, and the distance from the tooth edge 9 of the rotor is 1.16%-3.48% of the pole width of the rotor 2. The distance between the 5 tooth tops is 1.43%-5.73% of the highest value of the rotor 2.

The rotor teeth 5 of the rotor 2 are provided with internal auxiliary grooves of the rotor teeth. The auxiliary slots inside the rotor tooth poles are parallelogram auxiliary slots 7 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the stator tooth edge 8 is the tooth edge of the stator tooth 4 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary slot of the stator tooth pole The side length is 3.03%-15.15% of the pole width of stator 1, the distance from stator tooth edge 8 is 1.51%-15.1% of the pole width of stator 1, and the distance from the top of stator tooth 4 is 1.21% of the pole width of stator 1 -6.05%.

Specifically, the torque ripple coefficient is (T1-T2)/T3=0.73; among them, T1 is the maximum torque value when the motor is running stably, T2 is the minimum torque value when the motor is running stably, and T3 is the value when the motor is running stably average torque value. The internal auxiliary groove of the rotor tooth pole is set on the tooth end of the rotor tooth 5 on the side where the rotor tooth 5 and the stator tooth 4 preferentially contact; On the tooth end of the stator tooth 4 on the side.

Further, referring to FIG. 5 , design is carried out using the structural parameters of the wide rotor tooth 5 bearingless switched reluctance motor. Referring to Figure 2, by calculating the specific motor structure parameters, the side length of the square auxiliary slot 6 inside the stator tooth 4 pole of the motor is 0.2mm-1mm, which is 0.7mm in this example; the distance from the stator tooth edge is 8 The range of distance is 0.1mm-1mm, which is taken as 0.4mm; the distance from the top of stator tooth 4 is in the range of 0.2mm-1mm, which is taken as 0.4mm. Referring to Fig. 3, by calculating the specific motor structure parameters. The length range of the parallelogram auxiliary slot 7 inside the rotor tooth 5 of the motor is 1mm-2mm, which is taken as 2mm in this example; the height range is 1mm-1.4mm, which is taken as 1.2mm; the distance from the rotor tooth edge 9 is 0.15mm-0.45mm, which is taken as 0.15mm; the distance from the tooth top of the rotor tooth 5 is in the range of 0.1mm-0.4mm, which is taken as 0.1mm.

Further, as shown in Figure 6 is the radial magnetic density comparison chart of the original model and the improved model; the maximum radial magnetic density of the original model in the figure is 1.43T, and the maximum radial magnetic density of the improved model is 1.2T, which reduces the 16.1%. As shown in Figure 7, the maximum tangential magnetic density of the original model is 0.31T, and the maximum tangential magnetic density of the improved model is 0.43T, an increase of 38.7%.

Figure 8 is a schematic diagram of the direction of the magnetic force lines of the original model, and Figure 9 is a schematic diagram of the direction of the magnetic force lines of the improved model.

It can be seen that the addition of square auxiliary slots 6 can change the direction of the magnetic force lines inside the 4 poles of the stator teeth, so that the tangential component of the magnetic force lines increases and the radial component decreases. Fig. 10 is a simulation diagram of the direction of the magnetic force lines without the square auxiliary groove 6 in the original model; Fig. 11 is a simulation diagram of the improved direction of the magnetic force lines. In this example, the side length of the parallelogram auxiliary groove 7 inside the 5 poles of the rotor tooth ranges from 1 to 2mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 12 and Figure 13. When the side length is 2mm , the average torque of the motor is the largest, and the torque ripple is the smallest. Therefore, in this program, the side length of the parallelogram auxiliary groove 7 is selected as 2mm. In this example, the height of the parallelogram auxiliary groove 7 inside the 5 poles of the rotor tooth ranges from 1 to 1.4mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 14 and Figure 15. When the height is 1.2mm , the average torque of the motor is the largest, and the torque ripple is small, so the height of the parallelogram auxiliary groove 7 is selected as 1.2mm in this scheme. In this example, the distance between the parallelogram auxiliary groove 7 inside the rotor tooth 5 pole and the rotor tooth edge 9 is 0.15-0.45mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 16 and Figure 17. When When the distance is 0.15mm, the average torque of the motor is the largest and the torque ripple is the smallest. Therefore, the distance between the parallelogram auxiliary groove 7 and the rotor tooth edge 9 is 0.15mm in this scheme. In this example, the distance between the parallelogram auxiliary groove 7 inside the rotor tooth 5 pole and the rotor tooth 5 tooth top is 0.1-0.4mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 18 and Figure 19. When When the distance is 0.1mm, the average torque of the motor is the largest and the torque ripple is the smallest. Therefore, in this project, the distance between the parallelogram auxiliary groove 7 and the tooth top of the rotor tooth 5 is 0.1mm. In this example, the side length of the square auxiliary groove 6 inside the 4 poles of the stator teeth ranges from 0.2 to 1mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 20 and Figure 21. When the side length is 0.7mm, The average torque of the motor is large, and the torque ripple is the smallest. Therefore, the side length of the square auxiliary groove 6 is selected as 0.7mm in this scheme. In this example, the distance between the square auxiliary groove 6 inside the stator tooth 4 pole and the stator tooth edge 8 is 0.1-1mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 22 and Figure 23. When the distance is When the value is 0.4mm, the average torque of the motor is larger and the torque ripple is the smallest. Therefore, the distance between the square auxiliary groove 6 and the stator tooth edge 8 is selected as 0.4mm in this scheme. In this example, the distance between the inner square auxiliary slot 6 of the stator tooth 4 pole and the top of the stator tooth 4 is 0.2-1mm, and its influence on the average torque and torque ripple of the motor is shown in Figure 24 and Figure 25. When the distance is When the value is 0.4mm, the average torque of the motor is larger and the torque ripple is the smallest. Therefore, the distance between the square auxiliary slot 6 and the tooth top of the stator tooth 4 is selected as 0.4mm in this scheme.

Example

On the basis of Embodiment 1 or Embodiment 2; it is suitable for a three-phase 12/8-pole switched reluctance motor or a three-phase 12/8-pole bearingless switched reluctance motor; the stator 1 uses 12 sets of stator windings 3 .

Specifically, as shown in FIGS. 1-3 , a bearingless switched reluctance motor with a tooth structure includes: a doubly salient pole stator and rotor 2, including a rotor 2, and stators 1 and 12 sleeved on the periphery of the rotor 2 Set stator winding 3. Both the stator 1 and the rotor 2 are salient pole structures. The stator 1 is provided with several sets of stator teeth 4 correspondingly extending toward the rotor 2 ; the rotor 2 is provided with several sets of rotor teeth 5 extending outward; the stator teeth 4 are provided with several sets of stator windings 3 .

The inner side of the stator teeth 4 is provided with internal auxiliary grooves of the stator tooth poles; the internal auxiliary grooves of the stator tooth poles are square auxiliary grooves 6 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the rotor tooth edge 9 is the tooth edge of the rotor tooth 5 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary groove of the rotor tooth pole The side length is 14.3%-28.6% of the pole width of the rotor 2, the height is 7.75%-10.85% of the pole width of the rotor 2, and the distance from the tooth edge 9 of the rotor is 1.16%-3.48% of the pole width of the rotor 2. The distance between the 5 tooth tops is 1.43%-5.73% of the highest value of the rotor 2.

The rotor teeth 5 of the rotor 2 are provided with internal auxiliary grooves of the rotor teeth. The auxiliary slots inside the rotor tooth poles are parallelogram auxiliary slots 7 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the stator tooth edge 8 is the tooth edge of the stator tooth 4 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary slot of the stator tooth pole The side length is 3.03%-15.15% of the pole width of stator 1, the distance from stator tooth edge 8 is 1.51%-15.1% of the pole width of stator 1, and the distance from the top of stator tooth 4 is 1.21% of the pole width of stator 1 -6.05%.

Specifically, the torque ripple coefficient is (T1-T2)/T3=0.73; among them, T1 is the maximum torque value when the motor is running stably, T2 is the minimum torque value when the motor is running stably, and T3 is the value when the motor is running stably average torque value.

The internal auxiliary groove of the rotor tooth pole is set on the tooth end of the rotor tooth 5 on the side where the rotor tooth 5 and the stator tooth 4 preferentially contact; On the tooth end of the stator tooth 4 on the side.

Example

On the basis of Embodiment 1 or Embodiment 2; it is suitable for a three-phase 12/8-pole switched reluctance motor or a three-phase 12/8-pole bearingless switched reluctance motor; the stator 1 uses 12 sets of stator windings 3 .

Specifically, as shown in FIGS. 1-3 , a bearingless switched reluctance motor with a tooth structure includes: a doubly salient pole stator and rotor 2, including a rotor 2, and stators 1 and 12 sleeved on the periphery of the rotor 2 Set stator winding 3. Both the stator 1 and the rotor 2 are salient pole structures. The stator 1 is provided with several sets of stator teeth 4 correspondingly extending toward the rotor 2 ; the rotor 2 is provided with several sets of rotor teeth 5 extending outward; the stator teeth 4 are provided with several sets of stator windings 3 .

The inner side of the stator teeth 4 is provided with internal auxiliary grooves of the stator tooth poles; the internal auxiliary grooves of the stator tooth poles are square auxiliary grooves 6 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the rotor tooth edge 9 is the tooth edge of the rotor tooth 5 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary groove of the rotor tooth pole The side length is 14.3%-28.6% of the pole width of the rotor 2, the height is 7.75%-10.85% of the pole width of the rotor 2, and the distance from the tooth edge 9 of the rotor is 1.16%-3.48% of the pole width of the rotor 2. The distance between the 5 tooth tops is 1.43%-5.73% of the highest value of the rotor 2.

The rotor teeth 5 of the rotor 2 are provided with internal auxiliary grooves of the rotor teeth. The auxiliary slots inside the rotor tooth poles are parallelogram auxiliary slots 7 . The counterclockwise direction is the rotation direction of the rotor 2 when the motor is running; the stator tooth edge 8 is the tooth edge of the stator tooth 4 in the contact direction between the stator tooth 4 and the rotor tooth 5 when the motor rotor 2 rotates; the internal auxiliary slot of the stator tooth pole The side length is 3.03%-15.15% of the pole width of stator 1, the distance from stator tooth edge 8 is 1.51%-15.1% of the pole width of stator 1, and the distance from the top of stator tooth 4 is 1.21% of the pole width of stator 1 -6.05%.

Specifically, the torque ripple coefficient is (T1-T2)/T3=0.73; among them, T1 is the maximum torque value when the motor is running stably, T2 is the minimum torque value when the motor is running stably, and T3 is the value when the motor is running stably average torque value.

The internal auxiliary groove of the rotor tooth pole is set on the tooth end of the rotor tooth 5 on the side where the rotor tooth 5 and the stator tooth 4 preferentially contact; On the tooth end of the stator tooth 4 on the side.

Example

On the basis of Embodiment 1 or Embodiment 2 or Embodiment 3 or Embodiment 4; a method for changing the average torque of the motor, using a tooth-shaped structure of a bearingless switched reluctance motor, including the following content: through the stator of the motor 1 and the structure of rotor 2 are changed to enhance the average torque of the motor and greatly reduce the torque ripple of the motor.

There are parallelogram auxiliary slots 7 inside the rotor teeth 5, and square auxiliary slots 6 inside the stator teeth 4, which can increase the reluctance in the magnetic circuit, change the direction of the magnetic force lines, and then weaken the radial magnetic density in the air gap and increase the tangential direction. The magnetic density can increase the average torque and greatly reduce the torque ripple.

The magnetic flux is always closed along the path with the least reluctance, and parallelogram auxiliary slots 7 are set inside the teeth of the rotor teeth 5, which can increase the reluctance in the magnetic circuit and change the direction of the magnetic force lines so that the magnetic force lines pass through the parallelogram auxiliary slots 7 and the rotor. The magnetic circuit between the tooth tops of the teeth 5 enters the rotor 2, thereby changing the angle at which the magnetic flux enters the rotor teeth 5, reducing the radial magnetic density in the air gap, increasing the tangential magnetic density, and increasing the average torque. Reduced inherent torque ripple.

A square auxiliary slot 6 is set inside the tooth pole of the stator tooth 4, which increases the reluctance in the magnetic circuit and changes the direction of the magnetic force line, so that when the magnetic force line passes through the square auxiliary slot 6 and the motor rotor 2 rotates, the contact direction of the stator and rotor teeth 5 The magnetic circuit between the tooth edges 8 of the stator teeth, so that part of the magnetic field lines are squeezed, and enter the rotor teeth 5 through the non-overlapping area of the stator and rotor teeth 5; the radial force generated in the overlapping area of the stator and rotor teeth 5 is the effective radial force , the radial component of the magnetic force lines in the non-overlapping area of the stator and rotor teeth 5 is an ineffective component, while the tangential force is generated at the edge of the two overlapping areas, then the tangential component of this part is an effective component, and finally a further reduction in torque ripple can be achieved .

working principle:

As shown in Figures 1-25, the tooth-shaped structure of the bearingless switched reluctance motor in the present invention is an example of a 12/8 pole-wide rotor tooth 5 bearingless switched reluctance motor, through the motor stator 1 and rotor 2 The change of the structural form enhances the average torque of the motor, greatly reduces the torque ripple of the motor, and improves the performance of the motor. The structure and working principle of the wide rotor tooth 5 bearingless switched reluctance motor are relatively simple. The mechanical angle of the rotor tooth 5 is increased from 15° of the traditional bearingless switched reluctance motor to 30°. This change solves the problem of the traditional BSRM torque and the coupling problem of suspension force. However, the doubly salient pole structure and switching power supply of the motor have not been changed, resulting in the inherent torque ripple still existing. The existence of torque ripple will affect the smooth operation of the motor and aggravate the vibration of the motor, thereby accelerating the wear of the motor shaft and other components and reducing the service life of the worn parts, which affects the popularization and use of the bearingless switched reluctance motor. The rotor teeth 5 of the present invention are provided with parallelogram auxiliary slots 7 inside, and the stator teeth 4 are provided with square auxiliary slots 6, which can increase the reluctance in the magnetic circuit, change the direction of the magnetic force lines, and further weaken the radial magnetic density in the air gap. Increase the tangential magnetic density to achieve the purpose of increasing the average torque and greatly reducing the torque ripple.

More specifically, based on the minimum reluctance principle of BSRMWR, that is, the magnetic flux always closes along the path with the least reluctance, opening parallelogram auxiliary slots 7 inside the rotor teeth 5 can increase the reluctance in the magnetic circuit and change The direction of the magnetic force line makes the magnetic force line enter the rotor 2 through the magnetic circuit between the parallelogram auxiliary groove 7 and the tooth top of the rotor tooth 5, thereby changing the angle at which the magnetic flux enters the rotor tooth 5, so that the radial magnetic density in the air gap is reduced. The increase of tangential flux density increases the average torque of BSRMWR and reduces the inherent torque ripple.

A square auxiliary slot 6 is set inside the tooth pole of the stator tooth 4, which increases the reluctance in the magnetic circuit and changes the direction of the magnetic force line, so that when the magnetic force line passes through the square auxiliary slot 6 and the motor rotor 2 rotates, the contact direction of the stator and rotor teeth 5 The magnetic circuit between the tooth edges 8 of the stator teeth, so that part of the magnetic field lines are squeezed, and enter the rotor teeth 5 through the non-overlapping area of the stator teeth 5 . Because only the radial force generated in the overlapping area of the stator and rotor teeth 5 is the effective radial force, the radial component of the magnetic force lines in the non-overlapping area of the stator and rotor teeth 5 is an ineffective component, while the tangential force is generated in the two overlapping areas edge, then the tangential component of this part is an effective component, which can finally achieve the purpose of further reducing torque ripple.

The simulation test is carried out by passing the same current to the BSRMWR adopting the new tooth structure of the present invention and the traditional BSRMWR respectively by means of current chopping control. Although the improvement scheme of the prior art can reduce the torque ripple, it does not take into account the average torque of the motor, and may even reduce the average torque. This solution can increase the minimum value of the synthetic torque, greatly reduce the torque ripple of the motor, and at the same time increase the average torque of the motor. Fig. 4 is a comparative diagram of the output torque of the BSRMWR adopting the new tooth structure of the present invention and the traditional BSRMWR in steady state operation. During the steady-state operation of the motor, the average output torque of the BSRMWR adopting the novel tooth structure of the present invention is 0.802N.m, and the average output torque of the traditional BSRMWR is 0.762N.m, and the average torque is increased by 5.25%. According to the calculation formula of the torque ripple coefficient: (maximum torque value during stable operation of the motor-minimum torque value during stable operation of the motor)/average torque value during stable operation of the motor, it can be obtained: adopt the new tooth shape of the present invention The torque ripple coefficient of the structured BSRMWR is 0.73, and the torque ripple coefficient of the traditional BSRMWR is 1.22, and the torque ripple coefficient is reduced by 40.2%. According to the calculation results, it can be seen that the BSRMWR with the new tooth structure of the present invention can achieve the purpose of increasing the average torque and greatly reducing the torque ripple.

The above is inspired by the ideal embodiment of the present invention. Through the above description, relevant personnel can make various changes and modifications within the scope of not departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, and must be determined according to the scope of the claims.

Claims (10)

1. The bearingless switch reluctance motor with the tooth-shaped structure is characterized by comprising a doubly salient stator and a doubly salient rotor, wherein the doubly salient stator and the doubly salient rotor comprise a rotor and a stator sleeved on the periphery of the rotor;

a plurality of groups of stator teeth which extend towards the rotor correspondingly are arranged on the stator;

the rotor is provided with a plurality of groups of rotor teeth extending outwards;

a plurality of stator windings are wound on the stator teeth;

the inner side of the stator teeth is provided with an auxiliary groove inside the stator teeth pole

The rotor teeth of the rotor are provided with auxiliary grooves inside rotor teeth poles.

2. The bearingless switched reluctance motor of tooth structure of claim 1 wherein: the auxiliary grooves in the rotor tooth poles adopt parallelogram auxiliary grooves.

3. The bearingless switched reluctance motor of tooth structure of claim 2 wherein: the auxiliary grooves in the stator teeth are square auxiliary grooves.

4. A bearingless switched reluctance motor of tooth construction according to claim 3, wherein: the anticlockwise direction is taken as the rotation direction of the rotor when the motor operates;

the stator tooth edge is the tooth edge of the stator tooth in the contact direction of the stator tooth and the rotor tooth when the motor rotor rotates;

the side length of the auxiliary groove in the stator tooth pole is 3.03% -15.15% of the stator pole width, the distance from the tooth edge of the stator tooth is 1.51% -15.1% of the stator pole width, and the distance from the tooth top of the stator tooth is 1.21% -6.05% of the stator pole height.

5. The tooth construction bearingless switched reluctance motor of claim 4 wherein: the anticlockwise direction is taken as the rotation direction of the rotor when the motor operates;

the rotor tooth edge is the tooth edge of the rotor tooth in the contact direction of the stator tooth and the rotor tooth when the motor rotor rotates;

the side length of the auxiliary groove in the rotor tooth pole is 14.3% -28.6% of the extremely high rotor, the height is 7.75% -10.85% of the extremely wide rotor, the distance from the tooth edge of the rotor tooth pole is 1.16% -3.48% of the extremely wide rotor, and the distance from the tooth top of the rotor tooth pole is 1.43% -5.73% of the extremely high rotor.

6. The tooth construction bearingless switched reluctance motor of claim 5 wherein: the motor is suitable for a three-phase 12/8-pole switched reluctance motor or a three-phase 12/8-pole bearingless switched reluctance motor; the stator adopts 12 sets of stator windings.

7. The tooth construction bearingless switched reluctance motor of claim 5 wherein: the torque ripple coefficient is: (T1-T2)/t3=0.73; wherein T1 is the maximum torque value of the motor in stable operation, T2 is the minimum torque value of the motor in stable operation, and T3 is the average torque value of the motor in stable operation.

8. A bearingless switched reluctance motor of tooth construction according to claim 3, wherein: the rotor tooth pole internal auxiliary groove is arranged on the tooth end of the rotor tooth on one side where the rotor tooth is preferentially contacted with the stator tooth;

the stator tooth pole internal auxiliary groove is arranged on the tooth end of the stator tooth on one side where the stator tooth is preferentially contacted with the rotor tooth.

9. A method of varying the average torque of an electric motor, characterized in that a bearingless switched reluctance motor of the toothed structure of any one of claims 1-8 is employed; the method comprises the following steps:

the average torque of the motor is enhanced by changing the structural forms of the stator and the rotor of the motor, and the torque pulsation of the motor is greatly reduced.

10. The method of varying average motor torque according to claim 9, wherein:

the rotor teeth are internally provided with parallelogram auxiliary grooves, the stator teeth are internally provided with square auxiliary grooves, so that magnetic resistance in a magnetic circuit can be increased, the trend of magnetic lines of force can be changed, radial magnetic density in an air gap can be further weakened, tangential magnetic density can be increased, average torque can be increased, and torque pulsation can be greatly reduced;

the magnetic flux is always closed along the path with minimum magnetic resistance, and the parallelogram auxiliary grooves are formed in the rotor tooth poles, so that the magnetic resistance in the magnetic circuit can be improved, the trend of magnetic force lines is changed, the magnetic force lines enter the rotor through the magnetic circuit between the parallelogram auxiliary grooves and the rotor tooth tops, the angle of the magnetic flux entering the rotor teeth is changed, the radial magnetic density in an air gap is reduced, the tangential magnetic density is increased, the average torque is improved, and the inherent torque pulsation is reduced;

the square auxiliary grooves are formed in the tooth poles of the stator teeth, so that magnetic resistance in the magnetic circuit is increased, the trend of magnetic force lines is changed, and when the magnetic force lines rotate with a motor rotor through the square auxiliary grooves, the magnetic circuit between the tooth sides of the stator teeth in the contact direction of the stator teeth and the rotor teeth is enabled to be extruded, and part of the magnetic force lines enter the rotor teeth through the non-overlapping area of the stator teeth and the rotor teeth; the radial force generated in the overlapping area of the stator teeth and the rotor teeth is effective radial force, the radial component of the magnetic force lines in the non-overlapping area of the stator teeth and the rotor teeth is ineffective component, and the tangential force is generated at the edges of the two overlapping areas, so that the tangential component of the part is effective component, and finally, the torque pulsation can be further reduced.

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