Radial stator, magnetic levitation bearing, installation method, and motor

Abstract

A radial stator includes a stator core, and the stator core includes a stator outer ring. M magnetic poles are arranged on an inner circumferential wall of the stator outer ring, and are evenly distributed along the inner circumferential wall of the stator outer ring. The M magnetic poles include M.sub.1 magnetic poles arranged along the inner circumferential wall of the stator outer ring and M.sub.2 magnetic poles arranged along the inner circumferential wall of the stator outer ring; M2, M.sub.11, and M.sub.21; the M.sub.1 magnetic poles and the M.sub.2 magnetic poles are arranged on two sides of the stator outer ring with respect to a radial direction thereof, respectively; each of the M.sub.1 magnetic poles is provided with a first winding; and each of the M.sub.2 magnetic poles is provided with a second winding; and a coil turn N.sub.1 of the first winding is greater or less than a coil turn N.sub.2 of the second winding.

Claims

1. A radial stator, comprising a stator core, wherein: the stator core comprises a stator outer ring; M magnetic poles are arranged on an inner circumferential wall of the stator outer ring, and are evenly distributed along the inner circumferential wall of the stator outer ring; the M magnetic poles comprise M.sub.1 magnetic poles arranged along the inner circumferential wall of the stator outer ring and M.sub.2 magnetic poles arranged along the inner circumferential wall of the stator outer ring; M2, M.sub.11, and M.sub.21; the M.sub.1 magnetic poles and the M.sub.2 magnetic poles are arranged on two sides of the stator outer ring with respect to a radial direction thereof, respectively; each of the M.sub.1 magnetic poles is provided with a first winding; and each of the M.sub.2 magnetic poles is provided with a second winding; a coil turn N.sub.1 of the first winding is greater or less than a coil turn N.sub.2 of the second winding; in an installed state: the M.sub.1 magnetic poles are disposed above the M.sub.2 magnetic poles, and a coil turn N.sub.1 of the first winding is greater than a coil turn N.sub.2 of the second winding; and a following relationship is satisfied: $\frac{N_1}{N_2}=\sqrt{\frac{a+1}{a}}$ wherein a range of is: 0.1<<10.

2. The radial stator according to claim 1, wherein numbers of the magnetic poles satisfy M.sub.1=M.sub.2, and the M.sub.1 magnetic poles and the M.sub.2 magnetic poles are symmetrically distributed with respect to the radial direction of the stator outer ring.

3. The radial stator according to claim 2, wherein the numbers of the magnetic poles satisfy M=M.sub.1+M.sub.2.

4. The radial stator according to claim 1, wherein an indicating mark is made on the radial stator to indicate up and down positions of the magnetic poles during an installation of the radial stator.

5. A magnetic levitation bearing, comprising the radial stator of claim 1, and a rotor, wherein the radial stator is sleeved on the rotor.

6. An installation method for the magnetic levitation bearing of claim 5, comprising: confirming upper magnetic poles and lower magnetic poles; and locating the upper magnetic poles above the lower magnetic poles for installation.

7. A motor, comprising the magnetic levitation bearing of claim 5.

8. A radial stator, comprising a stator core, wherein: the stator core comprises a stator outer ring; M magnetic poles are arranged on an inner circumferential wall of the stator outer ring, and are evenly distributed along the inner circumferential wall of the stator outer ring; the M magnetic poles comprise M.sub.1 magnetic poles arranged along the inner circumferential wall of the stator outer ring and M.sub.2 magnetic poles arranged along the inner circumferential wall of the stator outer ring; M2, M.sub.11, and M.sub.21; the M.sub.1 magnetic poles and the M.sub.2 magnetic poles are arranged on two sides of the stator outer ring with respect to a radial direction thereof, respectively; each of the M.sub.1 magnetic poles is provided with a first winding; and each of the M.sub.2 magnetic poles is provided with a second winding; a coil turn N.sub.1 of the first winding is greater or less than a coil turn N.sub.2 of the second winding; in an installed state: the M.sub.2 magnetic poles are disposed above the M.sub.1 magnetic poles, and the coil turn N.sub.1 of the first winding is less than the coil turn N.sub.2 of the second winding; and a following relationship is satisfied: $\frac{N_1}{N_2}=\sqrt{\frac{a}{a+1}};$ wherein a range of is: 0.1<<10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other objectives, features and advantages of the present disclosure will become more obvious by describing the exemplary embodiments in detail combining with the accompanying drawings. The drawings described hereinafter are simply some embodiments of the present disclosure, and for those of ordinary skill in the art, other drawings may also be obtained according to these drawings without creative efforts.

(2) FIG. 1 shows a schematic structural view of a radial stator according to an embodiment of the present disclosure;

(3) FIG. 2 shows a schematic exploded structure view of a magnetic levitation bearing according to an embodiment of the present disclosure;

(4) FIG. 3 shows a schematic sectional view of the magnetic levitation bearing according to an embodiment of the present disclosure.

IN THE DRAWINGS

(5) 10. radial stator; 11. stator outer ring; 12. upper magnetic pole; 13. lower magnetic pole; 14. upper winding; 15. lower winding; 20. rotor.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(6) In order to make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be described clearly and completely hereinafter combining with the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are some but not all embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

(7) The terms used in the embodiments of the present disclosure are for the purpose of describing particular embodiments only, but not intended to limit the present disclosure. As used in the embodiments of the present disclosure and the appended claims, the singular forms a, the and this are intended to include the plural forms as well. Unless the context clearly dictates, otherwise, the term a plurality of generally means that at least two objects are included, but the case of including at least one object is not excluded.

(8) It should be understood that the term and/or used in the present disclosure is only used to describe an association relationship of the associated objects, and indicates that there may be three kinds of relationships, for example, A and/or B may indicate that A exists alone, and that A and B exist at the same time, and that B exists alone. In addition, the character / in the present disclosure generally indicates that there is an or relationship between the related front and back objects.

(9) It should also be noted that the terms comprise, contain or any other variation thereof are intended to encompass non-exclusive inclusion, such that a commodity or system comprising a series of elements comprises not only these elements, but also comprises other elements not listed explicitly or elements inherent to the commodity or system. Without further limitation, an element limited to be comprised via the phrase comprise a . . . does not exclude the presence of additional identical elements in the commodity or system that comprises the element.

(10) In the present disclosure, by arranging windings with different coil turns, an asymmetrical winding structure is formed on the multiple magnetic poles of the stator core, thereby reducing the inductances of some windings, improving the response speed of the coil, reducing resistances of some windings, reducing the heat generated by the coil, and further reducing the coil turns of some windings and reducing the production cost. The present disclosure will be described in detail hereinafter combining with specific embodiments.

(11) The present disclosure provides a radial stator, including a stator core. The stator core includes a stator outer ring. M magnetic poles are arranged on an inner circumferential wall of the stator outer ring and evenly distributed along the inner circumferential wall of the stator outer ring. The M magnetic poles include M.sub.1 magnetic poles arranged along the inner circumferential wall of the stator outer ring and M.sub.2 magnetic poles arranged along the inner circumferential wall of the stator outer ring. The M.sub.1 magnetic poles are arranged continuously and the M.sub.2 magnetic poles are arranged continuously, that is, the M magnetic poles include the continuously arranged M.sub.1 magnetic poles and the continuously arranged M.sub.2 magnetic poles, where M2, M.sub.11, and M.sub.21. The M.sub.1 magnetic poles and the M.sub.2 magnetic poles are arranged on two sides of the stator outer ring with respect to a radial direction thereof, respectively. Each of the M.sub.1 magnetic poles is provided with a first winding, and each of the M.sub.2 magnetic poles is provided with a second winding. That is, among the M magnetic poles, at least one magnetic pole is provided with the first winding, and at least one magnetic pole is provided with the second winding. The coil turn N.sub.1 of the first winding is greater or less than the coil turn N.sub.2 of the second winding, that is, the coil turns of the first winding and the second winding are different.

(12) In some embodiments, M.sub.1=M.sub.2, that is, the number of the magnetic poles provided with the first windings is the same as the number of the magnetic poles provided with the second windings. In some embodiments, the M.sub.1 magnetic poles and the M.sub.2 magnetic poles are arranged on the two sides of the stator outer ring with respect to the radial direction thereof, respectively, and are symmetrically distributed with respect to the radial direction of the stator outer ring.

(13) In this embodiment, M=M.sub.1+M.sub.2. That is, among the M magnetic poles, some magnetic poles are provided with the first windings, and the other magnetic poles are provided with the second windings.

(14) In an installation state of the radial stator, if the coil turn N.sub.1 of the first winding is greater than the coil turn N.sub.2 of the second winding, then the M.sub.1 magnetic poles are disposed above the M.sub.2 magnetic poles. If the coil turn N.sub.1 of the first winding is less than the coil turn N.sub.2 of the second winding, the M.sub.2 magnetic poles are disposed above the M.sub.1 magnetic poles. That is, the magnetic poles, which are provided with the windings with more coil turns, are arranged at upper positions; and the magnetic poles, which are provided with the windings with fewer coil turns, are arranged at lower positions, thereby avoiding redundant coils, reducing the coil inductance, improving the response speed, reducing the heat generated by the coil, and making the performance of the magnetic levitation bearing better.

(15) As shown in FIG. 1, in a specific embodiment, the M.sub.1 magnetic poles are defined as upper magnetic poles 12, and the M.sub.2 magnetic poles are defined as lower magnetic poles 13. In the installation state, the upper magnetic poles 12 are located above the lower magnetic poles 13, and the upper magnetic poles 12 and the lower magnetic poles 13 are all arranged along the stator outer ring 11 and radially extend inwards. In some embodiments, the upper magnetic poles 12, the lower magnetic poles 13, and the radial stator outer ring 11 are constructed as a unitary structure, for example, they may be formed by laminations of silicon steel sheets.

(16) In some embodiments, the number of the upper magnetic poles 12 is identical with the number of the lower magnetic poles 13, and the upper magnetic poles 12 and the lower magnetic poles 13 are symmetrically distributed with respect to a diameter of the stator outer ring 11. In this embodiment, three upper magnetic poles 12 and three lower magnetic poles 13 are arranged, and an interval between any two adjacent magnetic poles is the same.

(17) In this embodiment, the first winding is defined as an upper winding 14, the second winding is defined as a lower winding 15, and the coil turn of the upper winding 14 is greater than the coil turn of the lower winding 15.

(18) The upper winding 14 is arranged on the upper magnetic pole 12, the lower winding 15 is arranged on the lower magnetic pole 13, and the upper winding 14 and the lower winding 15 are wound on the magnetic poles clockwise or anticlockwise, respectively.

(19) In some embodiments, when the coil turn of the upper winding 14 is N.sub.1, and the coil turn of the lower winding 15 is N.sub.2, then

(20) $\frac{N_1}{N_2}=\sqrt{\frac{a+1}{a}}$

(21) A range of is 0.1<<10. Or, when the coil turn of the upper winding 14 is N.sub.2, the coil turn of the lower winding 15 is N.sub.1, then

(22) $\frac{N_1}{N_2}=\sqrt{\frac{a}{a+1}}$

(23) The range of is 0.1<<10.

(24) The present disclosure also provides a magnetic levitation bearing. As shown in FIG. 2 and FIG. 3, the magnetic levitation bearing includes the radial stator 10 above and a rotor 20. The radial stator 10 is sleeved on the rotor 20, and a gap is formed between the rotor 20 and an end of each magnetic pole of the radial stator 10. The upper winding 14 and the lower winding 15 are wound on the magnetic poles clockwise or anticlockwise, respectively. The upper magnetic poles 12 are located on an upper side of the rotor 20, and the lower magnetic poles 13 are located on a lower side of the rotor 20. A magnetic path is formed between the upper windings 14 to generate an upward resultant magnetic force, and a magnetic path is formed between the lower windings 15 to generate a downward resultant magnetic force.

(25) In the magnetic levitation bearing system, the forces exerted on the rotor 20 in operation mainly include its own gravity, a magnetic pulling force, and a centrifugal force for rotation. In the embodiment of the magnetic levitation bearing, the upper windings 14 need to balance the gravity of the rotor 20, the magnetic pulling force and the centrifugal force, and the lower windings 15 need to balance the magnetic pulling force and the centrifugal force. Let the gravity of the rotor 20 be F.sub.1=mg, and the resultant force of the magnetic pulling force and the centrifugal force be F.sub.2=F.sub.1, where a denotes a ratio of the resultant force of the magnetic pulling force and the centrifugal force exerted on the rotor to the gravity of the rotor, and is affected by motor dimensions and a rotation speed. The motor dimensions remain unchanged, and the rotation speed increases, then the value of a increases. The motor dimensions increase, the rotation speed remains unchanged, then the value of a decreases. Then the force needed to be provided by the upper windings 14 is F.sub.1+F.sub.2=(+1) mg, and the force needed to be provided by the lower windings 15 is F.sub.2= F= mg. According to a calculation formula of the electromagnetic force, the square of the coil turn of the winding is directly proportional to the electromagnetic force, so the relationship between the coil turn N.sub.1 of the upper winding 14 and the coil turn N.sub.2 of the lower winding 15 is:

(26) $\frac{N_1}{N_2}=\sqrt{\frac{a+1}{a}}$

(27) In some embodiments, the magnetic levitation bearing is an active magnetic levitation bearing, and the range of is set to be 0.1<<10, and the relationship between the coil turn of the upper winding 14 and the coil turn of the lower winding 15 is:

(28) $\sqrt{\frac{11}{10}}<\frac{N_1}{N_2}<\sqrt{11}$

(29) In some embodiments, a space-filling factor of the radial magnetic levitation bearing is in an allowable range of 0.5 to 0.8.

(30) In some embodiments, each of the upper windings 14 and each of the lower windings 15 may be controlled independently, and each winding may be controlled according to the state of the rotor 20. For example, when the position of the rotor 20 is centered, the forces provided by different windings are the same. If the rotor 20 deviates from the center to the upper left corner, the output force of the upper winding 14 at the upper left corner decreases, and the output force of the lower winding 15 at the lower right corner increases. If the rotor 20 deviates from the center to the upper right corner, the output force of the upper winding 14 at the upper right corner decreases, and the output force of the lower winding 15 at the lower left corner increases, etc., so as to balance the forces exerted on the rotor 20 and ensure that the air gaps between the rotor 20 and the magnetic poles are the same during operation of the rotor.

(31) After all windings are powered on, part of the electromagnetic force generated by the upper winding 14 is configured to balance the gravity of the rotor 20 itself. During the rotation, the rotor 20 may be subjected to a disturbance force and a centrifugal force generated due to a disequilibrium of the rotor 20 itself, the redundant electromagnetic force generated by the upper winding 14 and the electromagnetic force generated by the lower winding 15 are configured to balance these external forces exerted on the rotor 20, so that the rotor 20 may reach a stable operation state.

(32) In some embodiments, in order to facilitate the installation and make the installation more convenient, an indicating mark may be made on the magnetic levitation bearing. In some embodiments, the indicating mark may be made on an axial end surface of the stator outer ring 11. In some embodiments, indicating marks may be made on two end surfaces, so that the installation of the magnetic levitation bearing becomes more convenient. For example, the mark may be made on the stator outer ring 11, and the mark is made on the part where the upper magnetic poles 12 are arranged. For example, a word up may be marked, or a symbol, such as an arrow, may be marked.

(33) The present disclosure also provides an installation method of a magnetic levitation bearing, which is configured for installing the magnetic levitation bearing above. During an installation, positions of the upper winding 14 and the lower winding 15 are first confirmed, and the upper winding 14 is ensured to be positioned at the upper side during the installation process.

(34) The present disclosure also provides a motor, including the magnetic levitation bearing above, and is installed by using the installation method above. In some embodiments, the motor provided by the present disclosure is applicable to an equipment such as a compressor, to improve performance of the whole machine and reduce energy consumption.

(35) In the present disclosure, the asymmetrical winding structure is arranged, that is, the coil turns of the upper windings and the lower windings are different, thereby avoid redundant coils, reducing the inductance of the coil, improving the response speed, reducing the heat generated by the coil, and making the performance of the magnetic levitation bearing better.

(36) What illustrated and described are exemplary embodiments of the present disclosure. It should be understood that the present disclosure is not limited to the structure, the arrangements, or the implementations described in detail herein. On the contrary, the present disclosure is intended to cover various modifications and equivalent arrangements included within the spirits and scope of the appended claims.