Four-pole inner and outer double stator hybrid magnetic bearing

Abstract

The present invention relates to the field of non-mechanical contact magnetic bearings, and discloses a four-pole inner and outer double-stator hybrid magnetic bearing, comprising an inner stator, an outer stator and a rotor. The outer stator comprises left and right outer radial stator cores and an outer stator permanent magnet ring, and the inner stator comprises left and right inner radial stator cores and an inner stator permanent magnet ring; the inner and outer radial stator cores are positioned relative to each other; radial control windings are wound on the inner and outer radial stator cores; the rotor comprises a magnetic isolation aluminum ring and inner and outer rotor cores connected as a whole by the magnetic isolation aluminum ring, the outer rotor core and the outer stator core form an outer radial air gap, and the inner rotor core and the inner radial stator core form an inner radial air gap. In the present invention, the inner and outer stator permanent magnet rings work together to provide a static bias magnetic flux, the control windings on the inner and outer radial stators are energized to generate a control magnetic flux, and the inner and outer stators work together to generate a radial suspension force on the outer surface of the outer rotor core and the inner surface of the inner rotor core, thereby improving the suspension force density and radial bearing capacity.

Description

Technical Field

[0001] The present invention relates to the field of non-mechanical contact magnetic bearings, and in particular to a four-pole inner and outer double-stator hybrid magnetic bearing, which can be used as a contactless suspension support for high-speed transmission components such as flywheel systems, machine tool electric spindles, centrifuges, etc. Background Art

[0002] Magnetic bearings are a new type of high-performance bearing that uses the electromagnetic force between the stator and the rotor to suspend the rotor in space, so that there is no mechanical contact between the stator and the rotor. At present, magnetic bearings are divided into the following three types according to the way the magnetic force is provided: (1) Active magnetic bearings, in which the bias magnetic field is generated by the bias current, and the control magnetic flux generated by the control current is superimposed on the bias magnetic flux to generate a controllable suspension force. This type of magnetic bearing has a relatively large volume, weight and power consumption; (2) Passive magnetic bearings, in which the suspension force is completely provided by permanent magnets. The required controller is simple, the suspension power consumption is small, but the stiffness and damping are small. It is generally used to support objects in only one direction or to reduce the load acting on traditional bearings; (3) Hybrid magnetic bearings, in which permanent magnetic materials are used to replace the electromagnets in active magnetic bearings to generate the bias magnetic field. The control current only provides the control magnetic flux to balance the load or interference, which greatly reduces the power loss of the magnetic bearing, reduces the volume of the magnetic bearing, reduces its weight, and improves its carrying capacity.

[0003] The common feature of existing hybrid magnetic bearing structures is a single rotor and single stator structure, which only generates radial suspension force on the inside or outside of the rotor. The suspension force density is low and the radial bearing capacity is small, which makes it difficult to meet the performance requirements of some special applications. Summary of the invention

[0004] Purpose of the invention: In view of the problems existing in the prior art, the present invention provides a four-pole inner and outer double-stator hybrid magnetic bearing. The inner and outer stators of the hybrid magnetic bearing with this structure are wound with two sets of control windings, which generate radial suspension forces in the same direction on both the outside and inside of the rotor, effectively increasing the radial bearing capacity, with a compact structure, low power consumption and high suspension force density.

[0005] Technical solution: The present invention provides a four-pole inner and outer double-stator hybrid magnetic bearing, comprising an inner stator, an outer stator and a rotor, wherein the outer stator comprises a left outer radial stator core, a right outer radial stator core and an outer stator permanent magnet ring, and the inner stator comprises a left inner radial stator core, a right inner radial stator core and an inner stator permanent magnet ring; the left inner radial stator core and the right inner radial stator core are respectively opposite to the left outer radial stator core and the right outer radial stator core, and the outer stator permanent magnet ring is located between the left outer radial stator core and the right outer radial stator core; the inner stator permanent magnet ring is located between the left outer radial stator core and the right outer radial stator core; the inner stator permanent magnet ring is located between the left outer radial stator core and the right outer radial stator core. The left inner radial stator core and the right inner radial stator core are between the two cores; the left outer radial stator core, the right outer radial stator core, the left inner radial stator core and the right inner radial stator core are all wound with centralized radial control windings; the rotor comprises a rotor core and a magnetic isolation aluminum ring, and the rotor core is divided into an inner part and an outer part by the magnetic isolation aluminum ring, which are an outer rotor core and an inner rotor core respectively; an outer radial air gap is formed between the outer rotor core and the left outer radial stator core and the right outer radial stator core, and an inner radial air gap is formed between the inner rotor core and the left inner radial stator core and the right inner radial stator core.

[0006] Furthermore, the rotor core has an upper and lower "H"-shaped structure along the radial section, and the outer rotor core and the inner rotor core are respectively positioned opposite to the left outer radial stator core, the right outer radial stator core, the left inner radial stator core, and the right inner radial stator core.

[0007] Furthermore, the stator permanent magnet ring has the same outer diameter as the left outer radial stator core and the right outer radial stator core.

[0008] Furthermore, the inner circumferences of the left outer radial stator core and the right outer radial stator core are each provided with four suspended poles at intervals, the outer circumferences of the left inner radial stator core and the right inner radial stator core are also each provided with four suspended poles at intervals, and the radial control windings are all wound on the suspended poles.

[0009] Furthermore, the winding directions of the windings on the suspended poles in the Y direction on the left radial stator core are the same, and the winding directions of the windings on the suspended poles in the X direction are the same; the winding directions of the windings on the suspended poles in the Y direction on the right radial stator core are the same, and the winding directions of the windings on the suspended poles in the X direction are the same; and the corresponding windings on the left radial stator core and the right radial stator core are opposite, and then all the windings on the X poles are connected in series, and the windings on the Y poles are connected in series, and are driven by two switching power amplifiers respectively.

[0010] Furthermore, the left outer radial stator core, the right outer radial stator core, the left inner radial stator core, the right inner radial stator core, the outer rotor core, and the inner rotor core are made of a whole piece of magnetic conductive material; the outer stator permanent magnet ring and the inner stator permanent magnet ring are made of rare earth permanent magnet material. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The splitting and suspension magnetic flux diagram of the four-pole inner and outer double-stator hybrid magnetic bearing of the present invention;

[0012] Figure 2 This is the radial suspension flux diagram of the four-pole inner and outer double-stator hybrid magnetic bearing of the present invention.

[0013] Among them, 1-left outer radial stator core, 2-right outer radial stator core, 3-left inner radial stator core, 4-right inner radial stator core, 5-outer rotor core, 6-inner rotor core, 7-outer stator permanent magnet ring, 8-inner stator permanent magnet ring, 9-magnetic isolation aluminum ring, 10-radial control winding A, 11-radial control winding B, 12-radial control winding C, 13-radial control winding D, 14-outer radial air gap, 15-inner radial air gap, 16-static bias flux one, 17-static bias flux two, 18-outer radial suspension control flux, 19-inner radial suspension control flux. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0015] Specific implementation method Figure 1-2 As shown, the present invention discloses a four-pole inner and outer double stator hybrid magnetic bearing, including an inner stator, an outer stator and a rotor. The outer stator includes a left outer radial stator core 1, a right outer radial stator core 2 and an outer stator permanent magnet ring 7, and the inner stator includes a left inner radial stator core 3, a right inner radial stator core 4 and an inner stator permanent magnet 8. The rotor includes a rotor core and a magnetic isolation aluminum ring 9.

[0016] The left inner radial stator core 3 and the right inner radial stator core 4 are respectively opposite to the left outer radial stator core 1 and the right outer radial stator core 2, and the outer stator permanent magnet ring 7 is located between the left outer radial stator core 1 and the right outer radial stator core 2, and the left outer radial stator core 1 and the right outer radial stator core 2 are fixed by the outer stator permanent magnet ring 7. The inner stator permanent magnet ring 8 is located between the left inner radial stator core 3 and the right inner radial stator core 4, and the left inner radial stator core 3 and the right inner radial stator core 4 are fixed by the inner stator permanent magnet ring 8. In this embodiment, the outer diameter of the outer stator permanent magnet ring 7 is the same as that of the left outer radial stator core 1 and the right outer radial stator core 2.

[0017] The left outer radial stator core 1, the right outer radial stator core 2, the left inner radial stator core 3, and the right inner radial stator core 4 are all wound with centralized radial control windings, see the attached Figure 1, a radial control winding A10 is wound on the left outer radial stator core 1, a radial control winding B11 is wound on the right outer radial stator core 2, a radial control winding C12 is wound on the left inner radial stator core 3, and a radial control winding D13 is wound on the right inner radial stator core 4. In this embodiment, four suspended teeth are arranged at intervals on the inner circumference of the left outer radial stator core 1 and the right outer radial stator core 2, and four suspended teeth are also arranged at intervals on the outer circumference of the left inner radial stator core 3 and the right inner radial stator core 4, and the radial control windings (radial control winding A, radial control winding B, radial control winding C, radial control winding D) are all wound on the suspended teeth.

[0018] In the present embodiment, the rotor core is divided into two parts, an inner part and an outer part, by a magnetic insulating aluminum ring 9, which are an outer rotor core 5 and an inner rotor core 6 respectively. Moreover, the rotor core has an "H"-shaped structure along the radial section, and is divided into two parts, an inner part and an outer part, by the magnetic insulating aluminum ring 9 from the middle. The outer rotor core 5 is opposite to the left outer radial stator core 1 and the right outer radial stator core 2, and the inner rotor core 6 is opposite to the left inner radial stator core 3 and the right inner radial stator core 4.

[0019] The left outer radial stator core 1 and the right outer radial stator core 2 control the outer rotor core 5 outside the magnetic isolation aluminum ring 9, the left inner radial stator core 3 and the right inner radial stator core 4 control the inner rotor core 6 inside the magnetic isolation aluminum ring 9, the outer rotor core 5 and the left outer radial stator core 1 and the right outer radial stator core 2 form an outer radial air gap 14, and the inner rotor core 6 and the left inner radial stator core 3 and the right inner radial stator core 4 form an inner radial air gap 15.

[0020] The radial control winding A10, radial control winding B11, radial control winding C12 and radial control winding D13 are used for suspension control, and the radial control winding A10, radial control winding B11, radial control winding C12 and radial control winding D13 respectively include four windings in the displacement X and Y directions. Figure 2 As shown in . The radial control winding A10 and the radial control winding C12 have the same winding wires in the X direction and the same winding wires in the Y direction. The radial control winding B11 and the radial control winding D13 have the same winding wires in the X direction and the same winding wires in the Y direction. The corresponding windings on the radial control winding A10, the radial control winding C12, the radial control winding B11, and the radial control winding D13 are wound in opposite directions. The radial control winding A10, the radial control winding B11, the radial control winding C12, and the radial control winding D13 are connected in series in the X and Y directions to form the X and Y direction control windings, respectively. That is, all the windings on the X pole are connected in series, and the windings on the Y pole are connected in series, and are driven by two switching power amplifiers respectively.

[0021] The left outer radial stator core 1, the right outer radial stator core 2, the left inner radial stator core 3, the right inner radial stator core 4, the outer rotor core 5, and the inner rotor core 6 are made of a whole piece of magnetic conductive material. The outer stator permanent magnet ring 7 and the inner stator permanent magnet ring 8 are made of rare earth permanent magnet material.

[0022] The outer stator permanent magnet ring 7 provides a static bias flux 16, and the magnetic circuit of the static bias flux 16 is: the flux starts from the N pole of the outer stator permanent magnet ring 7, passes through the left outer radial stator core 1, the outer radial air gap 14, the outer rotor core 5, the outer radial air gap 14, and the right outer radial stator core 2 and returns to the S pole of the outer stator permanent magnet ring 7.

[0023] The inner stator permanent magnet ring 8 provides a static bias flux 17. The magnetic circuit of the static bias flux 17 is: the flux starts from the N pole of the inner stator permanent magnet ring 8, passes through the left inner radial stator core 3, the inner radial air gap 15, the inner rotor core 6, the inner radial air gap 15, and the right inner radial stator core 4 and returns to the S pole of the inner stator permanent magnet ring 8.

[0024] The outer radial suspension control magnetic flux 18 generated by energizing the radial control winding A and the radial control winding B has a magnetic circuit of: the left outer radial stator core 1, the outer radial air gap 14, the outer rotor core 5, and the left outer radial stator core 1 forming a closed loop.

[0025] The inner radial suspension control magnetic flux 19 generated by energizing the radial control winding C and the radial control winding D has a magnetic circuit of: the left inner radial stator core 3, the inner radial air gap 15, the inner rotor core 6, and the left inner radial stator core 3 form a closed loop.

[0026] Suspension principle: radial static bias flux 16, static bias flux 2 17 interact with outer radial suspension control flux 18 and inner radial suspension control flux 19, so that the magnetic field of the rotor outer air gap in the same direction as the rotor radial eccentricity is superimposed and weakened, while the magnetic field of the rotor outer air gap in the opposite direction is superimposed and enhanced, and the magnetic field of the rotor inner air gap in the same direction is superimposed and enhanced, while the magnetic field of the rotor inner air gap in the opposite direction is superimposed and weakened, and forces opposite to the rotor offset direction are generated on the inner and outer sides of the rotor respectively, pulling the rotor back to the radial equilibrium position.

[0027] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A four-pole inner and outer double stator hybrid magnetic bearing, comprising an inner stator, an outer stator and a rotor, characterized in that: The outer stator comprises a left outer radial stator core (1), a right outer radial stator core (2), and an outer stator permanent magnet ring (7); the inner stator comprises a left inner radial stator core (3), a right inner radial stator core (4), and an inner stator permanent magnet ring (8); the left inner radial stator core (3) and the right inner radial stator core (4) are respectively positioned opposite to the left outer radial stator core (1) and the right outer radial stator core (2); the outer stator permanent magnet ring (7) is located between the left outer radial stator core (1) and the right outer radial stator core (2); the inner stator permanent magnet ring (8) is located between the left inner radial stator core (3) and the right inner radial stator core (4); The left outer radial stator core (1), the right outer radial stator core (2), the left inner radial stator core (3), and the right inner radial stator core (4) are all wound with centralized radial control windings; the rotor comprises a rotor core and a magnetic isolation aluminum ring (9); the rotor core is divided into an inner and an outer part by the magnetic isolation aluminum ring (9), namely an outer rotor core (5) and an inner rotor core (6); an outer radial air gap (14) is formed between the outer rotor core (5) and the left outer radial stator core (1) and the right outer radial stator core (2); an inner radial air gap (15) is formed between the inner rotor core (6) and the left inner radial stator core (3) and the right inner radial stator core (4); The rotor core has an upper and lower "H"-shaped structure along the radial section, the outer rotor core (5) is opposite to the left outer radial stator core (1) and the right outer radial stator core (2), and the inner rotor core (6) is opposite to the left inner radial stator core (3) and the right inner radial stator core (4); The inner circumferences of the left outer radial stator core (1) and the right outer radial stator core (2) are both provided with four suspended poles at intervals, and the outer circumferences of the left inner radial stator core (3) and the right inner radial stator core (4) are also both provided with four suspended poles at intervals, and the radial control windings are all wound on the suspended poles.

2. The four-pole inner and outer double stator hybrid magnetic bearing according to claim 1 is characterized in that: The outer stator permanent magnet ring (7) has the same outer diameter as the left outer radial stator iron core (1) and the right outer radial stator iron core (2).

3. The four-pole inner and outer double stator hybrid magnetic bearing according to claim 1 is characterized in that: The windings on the suspended poles in the Y direction on the left outer radial stator core (1) and the left inner radial stator core (3) have the same winding direction, and the windings on the suspended poles in the X direction have the same winding direction; the windings on the suspended poles in the Y direction on the right outer radial stator core (2) and the right inner radial stator core (4) have the same winding direction, and the windings on the suspended poles in the X direction have the same winding direction; and the windings on the left outer radial stator core (1) and the left inner radial stator core (3) and the right outer radial stator core (2) and the right inner radial stator core (4) have opposite winding directions, and then all the windings on the X poles are connected in series, and the windings on the Y poles are connected in series, and are driven by two switching power amplifiers respectively.

4. The four-pole inner and outer double stator hybrid magnetic bearing according to any one of claims 1 to 3, characterized in that: The left outer radial stator core (1), the right outer radial stator core (2), the left inner radial stator core (3), the right inner radial stator core (4), the outer rotor core (5), and the inner rotor core (6) are made of a whole piece of magnetic conductive material; the outer stator permanent magnet ring (7) and the inner stator permanent magnet ring (8) are made of rare earth permanent magnet material.

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