An inductive rotor and a switched reluctance motor

Abstract

The present invention discloses an inductive rotor and a switched reluctance motor, belonging to the field of switched reluctance motors. The inductive rotor of the present invention includes a rotor core and a conducting ring. The rotor core is provided with salient poles, and the salient poles are provided with pole bodies. The conducting ring is arranged on the rotor by surrounding the pole bodies of the salient poles. The switched reluctance motor of the present invention includes a rotor and a stator, and the rotor used therein adopts the above-mentioned inductive rotor. By arranging a conducting ring on the salient poles of the rotor core, an induced current is generated in the conducting ring during the working process to form induced magnetic poles, so that the magnetic circuit is concentrated on the rotor salient poles, thereby increasing the magnetic energy utilization rate and the output torque.

Description

Technical Field

[0001] The present invention relates to the field of switched reluctance motors, and particularly to an inductive rotor and a switched reluctance motor. Background Art

[0002] The principle of a switched reluctance motor is that the magnetic circuit always closes along the path with the minimum magnetic reluctance. The ideal magnetic circuit path is that the magnetic circuit starts from the energized salient pole of the stator core, passes through the air gap, then passes through the acting salient pole of the rotor core, then passes through the yoke of the rotor core, then passes through the acting salient pole of the rotor core again, and then passes through the air gap back to the energized salient pole of the stator core. However, due to the limitation of the magnetic saturation of the core and the characteristic of the magnetic circuit diverging outside the magnetic poles, part of the magnetic circuit will deviate from the designed path to close, and even generate a reverse torque, resulting in a reduction in the magnetic energy utilization rate and the output torque.

[0003] Furthermore, it is understood that the magnetic circuit always concentrates towards the magnetic poles. Since the salient poles of the switched reluctance motor do not have magnetic pole polarities, the magnetic circuit cannot be concentrated towards them, resulting in low magnetic energy utilization rate of the existing switched reluctance motors. Summary of the Invention

[0004] In order to improve the deficiencies of the prior art, the purpose of the present invention is to provide an inductive rotor and a switched reluctance motor. By arranging a conductive ring on the salient pole of the rotor core, an induced current is generated in the conductive ring during the working process to form an induced magnetic pole, so that the magnetic circuit is concentrated towards the rotor salient pole, thereby increasing the magnetic energy utilization rate and the output torque.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0006] An inductive rotor is applied to a switched reluctance motor. The rotor includes a rotor core and a conductive ring. The rotor core is provided with salient poles, and the salient poles are provided with pole bodies. The conductive ring is arranged on the rotor by surrounding the pole bodies of the salient poles.

[0007] In the present invention, further, the conductive rings on each of the salient poles are independent of each other.

[0008] In the present invention, further, the inductive rotor is applied to a q-phase switched reluctance motor with the number of stator core poles being m, q≥3, the number of salient poles on the rotor core being n, n≥2, and m / n = q. The salient poles are further provided with pole wings. The left and right sides of the radially outer end of the pole body are respectively connected to the pole wings. The pole wings extend outward away from the pole body, and in the extending direction, the radially outer side surface of the pole wing gradually decreases in distance from the center of the rotor core. On this basis, preferably, the radially outer side surface of the pole wing is an arc surface. The two pole wings on the same rotor core salient pole are of equal size, symmetric in structure and on the same arc surface. The center point of the arc surface is arranged on the center line of the pole body, and the radius r of the arc surface is less than the radius R of the rotor core.

[0009] In the present invention, further, the inductive rotor is applied to a q-phase switched reluctance motor with the number of stator core poles being m, q≥3, the number of salient poles on the rotor core being n, n≥2, and m / n = q. The salient poles are further provided with pole wings. The left and right sides of the radially outer end of the pole body are respectively connected to the pole wings. The pole wings and the pole body are in a stepped shape with the pole body being high and the pole wings being low. The pole wings extend outward away from the pole body. The radially outer side of the pole wings is in a stepped shape, and in the extending direction of the pole wings, the distance between the radially outer side of the pole wings and the center of the rotor core changes in a stepped manner and decreases; the number of steps on the left and right sides of the pole body is x respectively, x≥2.

[0010] In the present invention, further, the conductive ring is made of copper or aluminum.

[0011] The present invention also provides a switched reluctance motor, including a rotor and a stator, and the rotor adopts the above-mentioned inductive rotor.

[0012] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0013] 1. By arranging a conductive ring on the salient poles of the rotor core in the present invention, during the working process, the conductive ring generates an induced current to form an induced magnetic pole, making the magnetic circuit concentrate on the rotor salient poles. When the rotor rotates at a low speed, the change of the magnetic field slows down, the induced current weakens, and the performance of the motor tends to show the characteristics of a pure switched reluctance motor, retaining the strong starting ability of the switched reluctance motor; when the rotor rotates at a high speed, the change of the magnetic field speeds up, the induced current generated by the conductive ring increases to generate an induced magnetic pole, and the acting salient poles of the rotor generate a permanent magnetic polarity, thus increasing the output torque and output power. Through this setting, the advantages of partial synchronous motors and asynchronous motors are integrated, making the motor performance more excellent. Through experiments, under the same voltage and a speed greater than 1 / 3 of the rated speed, and when the other structures of two groups of switched reluctance motors are the same, in one group of switched reluctance motors, the rotor is provided with a conductive ring, and in the other group of switched reluctance motors, the rotor is not provided with a conductive ring. The output power of the motor with the conductive ring can be increased by at least 10%.

[0014] 2. For a switched reluctance motor with the number of stator core poles being m and the number of salient poles of the rotor core being n, if the relationship of the pole number ratio is m / n = q, then pole wings are further arranged on the salient poles of the rotor core, thereby reducing the edge air gap. The radially outer side of the pole wings is an arc surface or a stepped surface, so that the air gap between the pole wings and the salient poles of the stator core forms a gradually changing air gap, thereby generating a gradually changing inductance, and further achieving the purpose of reducing the torque ripple of the switched reluctance motor. Description of the Drawings

[0015] Figure 1 It is a schematic plan view of an inductive rotor of the present invention.

[0016] Figure 2 It is a three-dimensional structural schematic diagram of an inductive rotor in Embodiment 1 of the present invention.

[0017] Figure 3 It is a planar structural schematic diagram of a switched reluctance motor with an inductive rotor in Embodiment 1 of the present invention.

[0018] Figure 4 It is a planar structural schematic diagram of an inductive rotor in Embodiment 2 of the present invention.

[0019] Figure 5 It is a planar structural schematic diagram of a switched reluctance motor with an inductive rotor in Embodiment 2 of the present invention

[0020] The meanings of the marks in the figure are: 100 - rotor, 110 - rotor core, 111 - salient pole, 111a - pole body, 111b - pole wing, 120 - conducting ring, 200 - stator. Detailed implementation manners

[0021] In order to make the objectives, technical solutions and advantages of the present invention clearer, the following further details the present invention through specific embodiments in combination with the attached Figures 1-5 , and further elaborates on the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] To improve the output torque of a switched reluctance motor, the present invention provides an inductive rotor. The inductive rotor 100 includes a rotor core 110 and a conducting ring 120. Salient poles 111 are provided on the rotor core 110. The salient poles 111 are provided with pole bodies 111a. The conducting ring 120 is arranged on the rotor 100 by surrounding the pole bodies 111a of the salient poles 111. In the present invention, the conducting ring 120 can be made of a conductive material such as copper or aluminum. By arranging the conducting ring 120 on the salient poles 111 of the rotor core in the present invention, during the working process, the conducting ring 120 generates an induced current to form an induced magnetic pole. When the rotor 100 rotates at a high speed, the magnetic field changes faster, the induced current generated by the conducting ring 120 increases to generate an induced magnetic pole, and the acting salient poles 111 of the rotor 100 generate a permanent magnetic polarity, thus increasing the output torque and output power.

[0023] The present invention preferably has the conducting rings 120 on the salient poles 111 independent of each other, so as to ensure that the magnetic circuit concentrates on each acting salient pole 111 on the rotor core 110, and maximize the utilization of magnetic energy.

[0024] The salient poles of the rotor core of the present invention can be conventional rectangular salient poles, and when applied to an ordinary switched reluctance motor, the purpose of increasing the utilization rate of magnetic energy and the output torque can be achieved.

[0025] In some preferred embodiments, the inductive rotor 100 can also be applied to a q-phase switched reluctance motor with the number of stator core poles being m, where q≥3. Let the number of salient poles 111 on the rotor core 110 be n, n≥2, and m / n = q. Then, the salient poles 111 of the rotor core of the present invention are preferably provided with pole wings 111b, that is, the pole wings 111b are respectively connected to the left and right sides of the radially outer end of the pole body 111a. Refer to Figure 1 and Figure 2 , the pole wings 111b extend outward away from the pole body 111a, and the radially outer side surface of the pole wings 111b decreases in distance from the center of the rotor core 110 in the extending direction. On this basis, preferably, the radially outer side surface of the pole wings 111b is an arc surface. The two pole wings 111b on the same rotor core salient pole 111 are of equal size, symmetric in structure, and on the same arc surface. The center point of the arc surface is set on the center line of the pole body 111a, and the radius r of the arc surface is smaller than the radius R of the rotor core 110. When the above rotor core 110 is applied to a switched reluctance motor, compared with a rectangular salient pole structure, the setting of the pole wings 111b can reduce the edge air gap. By setting the distance between the radially outer side surface of the pole wings 111b and the center of the rotor core 110 to decrease gradually, the air gap between it and the stator core salient pole 111 when applied to a switched reluctance motor is a gradually changing variable air gap, so as to generate a gradually changing inductance, and further achieve the purpose of reducing the torque ripple of the switched reluctance motor, and obtain a switched reluctance motor with smaller torque ripple.

[0026] In some preferred embodiments, the inductive rotor 100 is applied to a q-phase switched reluctance motor with the number of stator core poles being m, where q≥3. Let the number of salient poles 111 on the rotor core 110 be n, n≥2, and m / n = q. Then, the salient poles 111 of the rotor core of the present invention preferably further include pole wings 111b, that is, the pole wings 111b are respectively connected to the left and right sides of the radially outer end of the pole body 111a. The structural form of the pole wings 111b can also be further optimized, that is, the pole wings 111b and the pole body 111a are in a stepped shape with a high pole body 111a and a low pole wing 111b. Refer to Figure 4 , the pole wings 111b extend outward away from the pole body 111a. The radially outer side surface of the pole wings 111b is stepped, and in the extending direction of the pole wings 111b, the distance between the radially outer side surface of the pole wings 111b and the center of the rotor core 110 decreases in a stepped manner; the number of steps on the left and right sides of the pole body 111a is x respectively, where x≥2. By setting the stepped pole wings 111b, when the rotor core 110 is applied to a switched reluctance motor, a smoother change rate of the salient pole air gap volume can be obtained, making the torque ripple smoother accordingly, and further making the motor operation smoother.

[0027] Based on this, the present invention also provides a switched reluctance motor with an inductive rotor. Refer to Figure 3 and5 , including a rotor 100 and a stator 200, wherein the structure of the rotor 100 adopts the structure described above. By arranging a conducting ring 120 on the salient pole 111 of the rotor core, during the working process, the conducting ring 120 generates an induced current to form an induced magnetic pole, making the magnetic circuit concentrate on the rotor salient pole 111. When the rotor 100 rotates at a high speed, the magnetic field changes faster, the induced current generated by the conducting ring 120 increases to generate an induced magnetic pole, and the acting salient pole 111 of the rotor 100 generates a permanent magnetic polarity, thus increasing the output torque and output power. By arranging pole wings, a variable air gap is formed between the pole wings and the salient poles of the stator core, and a switched reluctance motor with smaller torque ripple is obtained at the same time.

[0028] Embodiment 1

[0029] Figures 1-2 Shown is a schematic structural diagram of an induction rotor of the present invention. The induction rotor 100 includes a rotor core 110 and a conducting ring 120. The rotor core 110 is provided with salient poles 111, and the salient poles 111 are provided with pole bodies 111a. The conducting ring 120 is arranged on the rotor 100 by surrounding the pole body 111a of the salient pole 111. The salient poles 111 of the rotor core 110 are further provided with pole wings 111b. The pole wings 111b are respectively connected to the left and right sides of the radially outer end of the pole body 111a. The pole wings 111b extend outward away from the pole body 111a, and the distance between the radially outer side surface of the pole wings 111b and the center of the rotor core 110 decreases in the extending direction.

[0030] Figure 3 Shown is a switched reluctance motor applying the induction rotor 100 of this embodiment. The number of poles of the stator core of the switched reluctance motor is m = 12, the number of phases is q = 3, and the number of salient poles 111 on the rotor core 110 is n = 3, satisfying the relationship of m / n = q. The salient poles 111 of the rotor core 110 are further provided with pole wings 111b, that is, the pole wings 111b are respectively connected to the left and right sides of the radially outer end of the pole body 111a. The pole wings 111b extend outward away from the pole body 111a, and the distance between the radially outer side surface of the pole wings 111b and the center of the rotor core 110 decreases in the extending direction.

[0031] Embodiment 2

[0032] Figure 4Another structural schematic diagram of the induction rotor of the present invention is shown. The induction rotor 100 includes a rotor core 110 and a conductive ring 120. The rotor core 110 is provided with salient poles 111, and the salient poles 111 are provided with pole bodies 111a. The conductive ring 120 is arranged on the rotor 100 by surrounding the pole bodies 111a of the salient poles 111. The salient poles 111 of the rotor core 110 are further provided with pole wings 111b. The left and right sides of the radially outer end of the pole body 111a are respectively connected to the pole wings 111b. The pole wings 111b and the pole body 111a are in a stepped shape with the pole body 111a being high and the pole wings 111b being low. The pole wings 111b extend outward away from the pole body 111a. The radially outer side of the pole wings 111b is stepped, and in the extending direction of the pole wings 111b, the distance between the radially outer side of the pole wings 111b and the center of the rotor core 110 changes in a stepped manner and decreases; the number of steps on the left and right sides of the pole body 111a is 4 respectively.

[0033] Figure 5 The shown switched reluctance motor applies the induction rotor 100 of this embodiment. The number of poles of the stator core of the switched reluctance motor is m = 12, the number of phases is q = 3, and the number of salient poles 111 on the rotor core 110 is n = 3, satisfying the relationship of m / n = q. The salient poles 111 of the rotor core 110 are further provided with pole wings 111b. The left and right sides of the radially outer end of the pole body 111a are respectively connected to the pole wings 111b. The pole wings 111b and the pole body 111a are in a stepped shape with the pole body 111a being high and the pole wings 111b being low. The pole wings 111b extend outward away from the pole body 111a. The radially outer side of the pole wings 111b is stepped, and in the extending direction of the pole wings 111b, the distance between the radially outer side of the pole wings 111b and the center of the rotor core 110 changes in a stepped manner and decreases; the number of steps on the left and right sides of the pole body 111a is 4 respectively.

[0034] After testing, under the conditions of the same voltage and a speed greater than 1 / 3 of the rated speed, and the other structures of the two groups of switched reluctance motors being the same, in one group of switched reluctance motors, the rotor is provided with a conductive ring, and in the other group of switched reluctance motors, the rotor is not provided with a conductive ring. The output power of the motor provided with the conductive ring can be increased by at least 10%.

[0035] Any invention and creation is achieved by the application and combination of existing technologies to create new things. There are infinite possibilities for the primary and secondary judgment of numerous technical problems and the application and combination of numerous technical means. The above description is only for the preferred embodiments of the present invention. It should be noted that due to the limited nature of language expression, there are objectively infinite specific structures. For those of ordinary skill in the art, without departing from the principle of the present invention, several improvements can be made, and these improvements should also be regarded as within the protection scope of the present invention.

Claims

1. A switched reluctance motor, comprising a rotor and a stator, which is a q-phase switched reluctance motor with the number of stator core poles being m, q≥3, characterized in that: the rotor includes a rotor core and a conducting ring; salient poles are provided on the rotor core; the salient poles are provided with pole bodies; the conducting ring is arranged on the rotor by surrounding the pole bodies of the salient poles; the conducting rings on each of the salient poles are independent of each other; the number of salient poles on the rotor core is n, n≥2, and m / n = q.

2. The switched reluctance motor according to claim 1, characterized in that: the salient poles are further provided with pole wings; the left and right sides of the radially outer end of the pole body are respectively connected to the pole wings; the pole wings extend outward away from the pole body, and in the extending direction, the distance between the radially outer side surface of the pole wing and the center of the rotor core decreases.

3. The switched reluctance motor according to claim 1, characterized in that: the salient poles are further provided with pole wings; the left and right sides of the radially outer end of the pole body are respectively connected to the pole wings; the pole wings and the pole body are in a stepped shape with the pole body being high and the pole wings being low; the pole wings extend outward away from the pole body, the radially outer side surface of the pole wing is stepped, and in the extending direction of the pole wing, the distance between the radially outer side surface of the pole wing and the center of the rotor core decreases in a stepped manner; the number of steps on the left and right sides of the pole body is x respectively, x≥2.

4. The switched reluctance motor according to claim 3, characterized in that: the radially outer side surface of the pole wing is an arc surface; the two pole wings on the same rotor core salient pole are of equal size, symmetric in structure and on the same arc surface; the center point of the arc surface is arranged on the center line of the pole body, and the radius r of the arc surface is less than the radius R of the rotor core.

5. The switched reluctance motor according to claim 1, characterized in that: the conducting ring is made of copper or aluminum.

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