Magnetic suspension active three-degree-of-freedom bearings, motors, compressors

Abstract

The present invention provides a magnetic suspension active three-degree-of-freedom bearing, a motor, and a compressor, wherein the magnetic suspension active three-degree-of-freedom bearing comprises: a bearing rotor fixedly sleeved on the outer peripheral wall of a rotating shaft, a radial stator sleeved on the outer side of the bearing rotor, a first axial stator and a second axial stator respectively sleeved on the outer side of the rotating shaft, and the first axial stator and the second axial stator are respectively located on both sides of the bearing rotor and the radial stator. According to the present invention, by removing the thrust disk of the magnetic suspension bearing, the radial position of the rotating shaft is adjusted by using the electromagnetic force between the radial stator and the bearing rotor, and the axial position of the rotating shaft is adjusted by using the electromagnetic force between the first axial stator and the second axial stator and the bearing rotor, thereby realizing the three-degree-of-freedom adjustment of the rotating shaft. The omission of the thrust disk makes the radial magnetic suspension bearing and the axial magnetic suspension bearing highly integrated, compact in structure, easy to assemble, and the bearing size is significantly reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic suspension bearings, and in particular relates to a magnetic suspension active three-degree-of-freedom bearing, a motor, and a compressor. Background Art

[0002] Magnetic bearings use the electromagnetic force on the rotor to suspend the rotating shaft, and the rotating shaft and stator remain in a non-contact state, so they have the advantages of no wear, high speed, high precision, and long life. Magnetic bearings are referred to as magnetic bearings. Magnetic bearings can be divided into three categories according to their working principles: active magnetic bearings, passive magnetic bearings, and hybrid magnetic bearings. Magnetic bearings include radial magnetic bearings and axial magnetic bearings. The radial magnetic bearing adjusts the radial position of the rotating shaft through the electromagnetic force between the bearing rotor and the fixed sleeve on the rotating shaft, and the axial magnetic bearing adjusts the axial position of the rotating shaft through the electromagnetic force between the thrust plate and the fixed sleeve on the rotating shaft, thereby realizing the three-degree-of-freedom adjustment of the rotating shaft. In the prior art, due to the existence of the thrust plate, the integration degree of radial magnetic bearings and axial magnetic bearings is not high, and the final formed magnetic bearing has a complex structure, difficult assembly, and large size. Summary of the invention

[0003] Therefore, the present invention provides a magnetically suspended active three-degree-of-freedom bearing, which can overcome the shortcomings of existing magnetic bearings such as complex structure, difficult assembly and large size.

[0004] In order to solve the above problems, the present invention provides a magnetically suspended active three-degree-of-freedom bearing, comprising: a rotating shaft, a bearing rotor, a radial stator, a first axial stator and a second axial stator, the bearing rotor is fixedly sleeved on the outer peripheral wall of the rotating shaft, the radial stator is sleeved on the outer side of the bearing rotor, a radial working gap is provided between the radial stator and the bearing rotor, the first axial stator and the second axial stator are respectively sleeved on the outer side of the rotating shaft, and the first axial stator and the second axial stator are respectively located on both sides of the bearing rotor and the radial stator at the same time; the radial stator comprises four pole units separated by four quadrants, the pole unit comprises a first pole, a second pole, a third pole and a fourth pole facing the inner side of the radial stator and arranged in sequence, and in the same quadrant, the first pole and The fourth pole has the same size and is symmetrical with respect to the angular bisector of the quadrant, the second pole and the third pole have the same size and are also symmetrical with respect to the angular bisector of the quadrant, and the first pole, the second pole, the third pole and the fourth pole are respectively wound with a first radial winding, a second radial winding, a third radial winding and a fourth radial winding; the first axial stator includes a first outer magnetic pole block and a first inner magnetic pole ring, a first axial winding is arranged between the first outer magnetic pole block and the first inner magnetic pole ring, and a first axial working gap is provided between the first inner magnetic pole ring and the bearing rotor; the second axial stator includes a second outer magnetic pole block and a second inner magnetic pole ring, a second axial winding is arranged between the second outer magnetic pole block and the second inner magnetic pole ring, and a second axial working gap is provided between the second inner magnetic pole ring and the bearing rotor.

[0005] In some embodiments, the number of the first outer magnetic pole blocks is six, and the six first outer magnetic pole blocks are distributed at intervals along the circumference of the first axial stator.

[0006] In some embodiments, the number of the second outer magnetic pole blocks is six, and the six second outer magnetic pole blocks are distributed at intervals along the circumference of the second axial stator.

[0007] In some embodiments, in two adjacent quadrants, two adjacent first poles are combined to form a first combination, two adjacent fourth poles are combined to form a second combination, the six first external magnetic pole blocks are respectively adapted to the positions of the two first combinations and the four third poles, and the six second external magnetic pole blocks are respectively adapted to the positions of the two second combinations and the four second poles.

[0008] In some embodiments, the first radial winding, the second radial winding, the third radial winding and the fourth radial winding are all energized to generate the first radial control magnetic circuit, the second radial control magnetic circuit and the third radial control magnetic circuit, and the first axial winding is energized to generate the first axial control magnetic circuit and the third axial control magnetic circuit, the direction of the magnetic lines of force of the first axial control magnetic circuit in the first pole is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit in the first pole, and the direction of the magnetic lines of force of the third axial control magnetic circuit in the third pole is the same as the direction of the magnetic lines of force of the second radial control magnetic circuit and the third radial control magnetic circuit in the third pole.

[0009] In some embodiments, the first axial control magnetic circuit passes through the first inner magnetic pole ring-the first axial working gap-the bearing rotor-the radial working gap-the first pole-the first outer magnetic pole block and returns to the first axial stator to close; the third axial control magnetic circuit passes through the first inner magnetic pole ring-the first axial working gap-the bearing rotor-the radial working gap-the third pole-the first outer magnetic pole block and returns to the first axial stator to close; the first radial control magnetic circuit passes through the second pole-the radial working gap-the bearing rotor-the radial working gap-the first pole to the radial stator to close; the second radial control magnetic circuit passes through the second pole-the radial working gap-the bearing rotor-the radial working gap-the third pole to the radial stator to close; the third radial control magnetic circuit passes through the fourth pole-the radial working gap-the bearing rotor-the radial working gap-the third pole to the radial stator to close.

[0010] In some embodiments, after the second axial winding is energized, a second axial control magnetic circuit and a fourth axial control magnetic circuit are generated, the direction of the magnetic lines of force of the second axial control magnetic circuit in the second pole is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit and the second radial control magnetic circuit in the second pole, and the direction of the magnetic lines of force of the fourth axial control magnetic circuit in the fourth pole is the same as the direction of the magnetic lines of force of the third radial control magnetic circuit in the fourth pole.

[0011] In some embodiments, the second axial control magnetic circuit passes through the second outer magnetic pole block-the second pole-the radial working gap-the bearing rotor-the second axial working gap-the second inner magnetic pole and returns to the second axial stator to close; the fourth axial control magnetic circuit passes through the second outer magnetic pole block-the fourth pole-the radial working gap-the bearing rotor-the second axial working gap-the second inner magnetic pole and returns to the second axial stator to close; the first radial control magnetic circuit passes through the second pole-the radial working gap-the bearing rotor-the radial working gap-the first pole to the radial stator to close; the second radial control magnetic circuit passes through the second pole-the radial working gap-the bearing rotor-the radial working gap-the third pole to the radial stator to close; the third radial control magnetic circuit passes through the fourth pole-the radial working gap-the bearing rotor-the radial working gap-the third pole to the radial stator to close.

[0012] In some embodiments, within the same pole unit, the first radial winding and the fourth radial winding are connected in series; the second radial winding and the third radial winding are connected in series.

[0013] In some embodiments, along the circumferential direction of the radial stator, the width of the second pole is greater than the width of the first pole.

[0014] In some embodiments, along the radial direction of the radial stator, the first radial winding, the second radial winding, the third radial winding, and the fourth radial winding are all located radially outside the first outer magnetic pole block and the second outer magnetic pole block.

[0015] The present invention also provides a motor, comprising the above-mentioned magnetic suspension active three-degree-of-freedom bearing.

[0016] The present invention also provides a compressor, comprising the above-mentioned magnetic suspension active three-degree-of-freedom bearing.

[0017] The present invention provides a magnetic suspension active three-degree-of-freedom bearing, motor, and compressor. The thrust plate is removed, and the radial position of the rotating shaft is adjusted by using the electromagnetic force between the radial stator and the bearing rotor, and the axial position of the rotating shaft is adjusted by using the electromagnetic force between the first axial stator and the second axial stator and the bearing rotor, thereby realizing three-degree-of-freedom adjustment of the rotating shaft, that is, the position of the rotating shaft in the three directions of XYZ can be freely adjusted. When realizing the three-degree-of-freedom adjustment of the rotating shaft, the thrust plate is omitted, so that the radial magnetic suspension bearing and the axial magnetic suspension bearing are highly integrated, compact in structure, easy to assemble, and the bearing size is significantly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a schematic structural diagram of a radial stator of a magnetically suspended active three-degree-of-freedom bearing according to an embodiment of the present invention;

[0019] Figure 2 for Figure 1 A cross-sectional view of the AA plane of the radial stator of the magnetically suspended active three-degree-of-freedom axis according to an embodiment of the present invention;

[0020] Figure 3 for Figure 1 A cross-sectional view of the BB plane of the radial stator of the magnetically suspended active three-degree-of-freedom axis according to an embodiment of the present invention;

[0021] Figure 4 It is a front view of a first axial stator of a magnetically suspended active three-degree-of-freedom bearing according to an embodiment of the present invention;

[0022] Figure 5 It is a front view of a second axial stator of a magnetically suspended active three-degree-of-freedom bearing according to an embodiment of the present invention;

[0023] Figure 6 It is a schematic structural diagram of the first axial stator of the magnetically suspended active three-degree-of-freedom bearing according to an embodiment of the present invention.

[0024] The reference numerals are:

[0025] 1. Rotating shaft; 2. Bearing rotor; 3. Radial stator; 31. First pole; 32. Second pole; 33. Third pole; 34. Fourth pole; 35. First radial winding; 36. Second radial winding; 37. Third radial winding; 38. Fourth radial winding; 4. First axial stator; 41. First outer magnetic pole block; 42. First inner magnetic pole ring; 43. First axial winding; 5. Second axial stator; 51. Second outer magnetic pole block; 52. Second inner magnetic pole ring; 53. Second axial winding; 6. Radial working gap; 7. First axial working gap; 8. Second axial working gap; 9. First radial control magnetic circuit; 10. Second radial control magnetic circuit; 11. Third radial control magnetic circuit; 12. First axial control magnetic circuit; 13. Second axial control magnetic circuit; 14. Third axial control magnetic circuit; 15. Fourth axial control magnetic circuit. DETAILED DESCRIPTION

[0026] See also Figures 1 to 6As shown, according to an embodiment of the present invention, a magnetically suspended active three-degree-of-freedom bearing is provided, comprising: a rotating shaft 1, a bearing rotor 2, a radial stator 3, a first axial stator 4 and a second axial stator 5, the bearing rotor 2 is fixedly sleeved on the outer peripheral wall of the rotating shaft 1, the radial stator 3 is sleeved on the outer side of the bearing rotor 2, a radial working gap 6 is provided between the radial stator 3 and the bearing rotor 2, the first axial stator 4 and the second axial stator 5 are respectively sleeved on the outer side of the rotating shaft 1, and the first axial stator 4 and the second axial stator 5 are respectively located on both sides of the bearing rotor 2 and the radial stator 3 at the same time; the radial stator 3 comprises four pole units separated by four quadrants, the pole unit comprises a first pole 31, a second pole 32, a third pole 33 and a fourth pole 34 facing the inner side of the radial stator 3 and arranged in sequence, and in the same quadrant, the first pole 31 and the fourth pole 34 have the same size and are relatively The second pole 32 and the third pole 33 are symmetrical about the angular bisector of the quadrant, the sizes of the second pole 32 and the third pole 33 are the same and are also symmetrical relative to the angular bisector of the quadrant, the first pole 31, the second pole 32, the third pole 33 and the fourth pole 34 are respectively wound with the first radial winding 35, the second radial winding 36, the third radial winding 37 and the fourth radial winding 38; the first axial stator 4 includes a first outer magnetic pole block 41 and a first inner magnetic pole ring 42, a first axial winding 43 is arranged between the first outer magnetic pole block 41 and the first inner magnetic pole ring 42, and a first axial working gap 7 is provided between the first inner magnetic pole ring 42 and the bearing rotor 2; the second axial stator 5 includes a second outer magnetic pole block 51 and a second inner magnetic pole ring 52, a second axial winding 53 is arranged between the second outer magnetic pole block 51 and the second inner magnetic pole ring 52, and a second axial working gap 8 is provided between the second inner magnetic pole ring 52 and the bearing rotor 2. In this technical solution, the thrust plate is removed, and the radial position of the rotating shaft 1 is adjusted by the electromagnetic force between the radial stator 3 and the bearing rotor 2, and the axial position of the rotating shaft 1 is adjusted by the electromagnetic force between the first axial stator 4 and the second axial stator 5 and the bearing rotor 2, thereby realizing the three-degree-of-freedom adjustment of the rotating shaft 1, that is, the position of the rotating shaft 1 in the three directions of XYZ can be freely adjusted. When realizing the three-degree-of-freedom adjustment of the rotating shaft 1, the thrust plate is omitted, so that the radial magnetic suspension bearing and the axial magnetic suspension bearing are highly integrated, compact in structure, easy to assemble, and the bearing size is significantly reduced. While having these advantages, the magnetic bearing can also increase the critical speed of the bearing rotor 2 and improve the stability and applicability of the magnetic suspension system. Among them, after the first radial winding 35 and the second radial winding 36 are both energized, the electromagnetic force generated is used to suspend the combination of the bearing rotor 2 and the shaft 1. When the radial position of the shaft 1 needs to be adjusted, it can be achieved by increasing the radial winding current in the corresponding quadrant or the corresponding combined quadrant; when the axial position of the shaft 1 needs to be adjusted, it can be achieved by increasing the current of the first axial winding 43 of the first axial stator 4 or increasing the current of the second axial winding 53 of the second axial stator 5.The number of poles of the radial stator 3 of the magnetic bearing will be different according to the change of its own size. The magnetic bearing within a certain size range corresponds to the corresponding number of poles. Otherwise, if the number of poles is too small, the spacing between adjacent poles will appear too large. If the number of poles is too large, the spacing between adjacent poles will be too small and difficult to wind. The magnetic active three-degree-of-freedom bearing of the present application corresponds to 16 poles according to its own size. More importantly, in the same quadrant, the first pole 31 and the fourth pole 34 have the same size and are symmetrical relative to the angular bisector of the quadrant, and the second pole 32 and the third pole 33 have the same size and are also symmetrical relative to the angular bisector of the quadrant. When the first radial winding 35, the second radial winding 36, the third radial winding 37 and the fourth radial winding 38 are supplied with current, in the quadrant, the resultant force of the electromagnetic force generated after power-on is always on the angular bisector of the quadrant, which is more conducive to adjusting the radial position of the bearing rotor 2, that is, more conducive to adjusting the radial position of the shaft 1. For the left and right first axial stators 4 and second axial stators 5, an outer magnetic pole block and an inner magnetic pole ring are arranged thereon, so that a recessed area is formed between the outer magnetic pole block and the inner magnetic pole ring, thereby facilitating the arrangement of the axial winding, and at the same time, the outer magnetic pole block can reduce the axial magnetic leakage of the radial stator 3. The first axial winding 43 and the second axial winding 53 are both single-coil modes, the first axial winding 43 is arranged around the first inner magnetic pole ring 42, and the second axial winding 53 is arranged around the second inner magnetic pole ring 52, that is, the first axial winding 43 and the second axial winding 53 are both arranged around the rotating shaft 1. When the axial winding is energized, the inner magnetic pole ring can apply a uniform electromagnetic force to the circumference of the bearing rotor 2, which is more conducive to adjusting the axial position of the bearing rotor 2, that is, it is more conducive to adjusting the axial position of the rotating shaft 1.

[0027] Specifically, the number of the first outer magnetic pole blocks 41 is six, and the six first outer magnetic pole blocks 41 are distributed at intervals along the circumferential direction of the first axial stator 4 .

[0028] See also Figure 4 and Figure 6 As shown, compared with setting the first outer magnetic pole as a whole outer magnetic ring, a plurality of first outer magnetic pole blocks 41 are evenly spaced and distributed in the circumference of the first axial stator 4. This can avoid the leakage of the radial magnetic circuit of each pole on the adjacent radial stator 3 on the outer circle of the first axial stator 4, and only enhance the air gap magnetic field on the radial pole.

[0029] Specifically, the number of the second outer magnetic pole blocks 51 is six, and the six second outer magnetic pole blocks 51 are distributed at intervals along the circumferential direction of the second axial stator 5 .

[0030] See also Figure 5As shown, compared with setting the second outer magnetic pole as a whole outer magnetic ring, a plurality of second outer magnetic pole blocks 51 are evenly spaced and distributed in the circumference of the second axial stator 5. This can avoid the leakage of the radial magnetic circuit of each pole on the adjacent radial stator 3 on the outer circle of the first axial stator 4, and only enhance the air gap magnetic field on the radial pole.

[0031] As a specific implementation, in two adjacent quadrants, two adjacent first poles 31 are combined to form a first combination, two adjacent fourth poles 34 are combined to form a second combination, six first outer magnetic pole blocks 41 are respectively adapted to the positions of the two first combinations and the four third poles 33, and six second outer magnetic pole blocks 51 are respectively adapted to the positions of the two second combinations and the four second poles 32. In this way, it is possible to avoid the magnetic field generated by the first axial winding 43 and the second axial winding 53 after being energized from acting on the same pole, and to prevent the magnetic flux on the same pole from being excessively saturated. Among them, from the first quadrant to the fourth quadrant, the arrangement of the four poles is: the first pole 31, the second pole 32, the third pole 33, the fourth pole 34, the fourth pole 34, the third pole 33, the second pole 32, the first pole 31, the first pole 31, the second pole 32, the third pole 33, the fourth pole 34, the fourth pole 34, the third pole 33, the second pole 32, the first pole 31. The first axial stator 4 and the second axial stator 5 have the same structure, except that they are relatively offset at a certain angle during assembly.

[0032] Specifically, when the first radial winding 35, the second radial winding 36, the third radial winding 37 and the fourth radial winding 38 are all energized, a first radial control magnetic circuit 9, a second radial control magnetic circuit 10 and a third radial control magnetic circuit 11 are generated. When the first axial winding 43 is energized, a first axial control magnetic circuit 12 and a third axial control magnetic circuit 14 are generated. The direction of the magnetic lines of force of the first axial control magnetic circuit 12 in the first pole 31 is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 in the first pole 31. The direction of the magnetic lines of force of the third axial control magnetic circuit 14 in the third pole 33 is the same as the direction of the magnetic lines of force of the second radial control magnetic circuit 10 and the third radial control magnetic circuit 11 in the third pole 33.

[0033] See also Figure 1 and Figure 2As shown, the current flow direction in the first radial winding 35 is right in and left out, the magnetic pole of the first pole 31 is the S pole, the current flow direction in the second radial winding 36 is left in and right out, the magnetic pole of the second pole 32 is the N pole, the current flow direction in the third radial winding 37 is right in and left out, the magnetic pole of the third pole 33 is the S pole, the current flow direction in the fourth radial winding 38 is left in and right out, the magnetic pole of the fourth pole 34 is the N pole, the current flow in the first axial winding 43 is downward in and upward out, and the magnetic pole of the first inner magnetic pole ring 42 is the N pole, then the direction of the magnetic lines of force of the first axial control magnetic circuit 12 in the first pole 31 can be the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 in the first pole 31, and the direction of the magnetic lines of force of the third axial control magnetic circuit 14 in the third pole 33 can be the same as the direction of the magnetic lines of force of the second radial control magnetic circuit 10 and the third radial control magnetic circuit 11 in the third pole 33. It is also possible to change the direction of current flow so that the current flow direction in the first radial winding 35 is left-in and right-out, then the magnetic pole of the first pole 31 is the N pole, the current flow direction in the second radial winding 36 is right-in and left-out, the magnetic pole of the second pole 32 is the S pole, the current flow direction in the third radial winding 37 is left-in and right-out, the magnetic pole of the third pole 33 is the N pole, the current flow direction in the fourth radial winding 38 is right-in and left-out, and the magnetic pole of the fourth pole 34 is the S pole, so that the current flow of the first axial winding 43 is upward-in and downward-out, then the magnetic pole of the first pole 31 is the S pole, and it is also possible to achieve that the direction of the magnetic lines of force of the first axial control magnetic circuit 12 in the first pole 31 is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 in the first pole 31, and the direction of the magnetic lines of force of the third axial control magnetic circuit 14 in the third pole 33 is the same as the direction of the magnetic lines of force of the second radial control magnetic circuit 10 and the third radial control magnetic circuit 11 in the third pole 33. When the direction of the magnetic force lines of the first axial control magnetic circuit 12 in the first pole 31 is the same as the direction of the magnetic force lines of the first radial control magnetic circuit 9 in the first pole 31, and the direction of the magnetic force lines of the third axial control magnetic circuit 14 in the third pole 33 is the same as the direction of the magnetic force lines of the second radial control magnetic circuit 10 and the third radial control magnetic circuit 11 in the third pole 33, that is, the axial magnetic circuit will not reduce the radial magnetic circuit, and the radial air gap magnetic flux will be enhanced, and the magnetic attraction of the first pole 31 and the third pole 33 to the bearing rotor 2 will be enhanced. However, this is only the influence of the axial magnetic flux on the pole in one quadrant, and the enhancement of the radial magnetic flux by the axial magnetic flux in the four quadrants is mutually offset, that is, although the radial magnetic circuit and the axial magnetic circuit of the integrated magnetic bearing both flow through the bearing rotor 2, even if the axial magnetic circuit changes, it will not affect the radial magnetic circuit as a whole, so that the axial magnetic circuit and the radial magnetic circuit each play their own role, simplifying the control of the magnetic bearing.

[0034] As a specific implementation, after the second axial winding 53 is energized, a second axial control magnetic circuit 13 and a fourth axial control magnetic circuit 15 are generated. The direction of the magnetic lines of force of the second axial control magnetic circuit 13 in the second pole 32 is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 and the second radial control magnetic circuit 10 in the second pole 32. The direction of the magnetic lines of force of the fourth axial control magnetic circuit 15 in the fourth pole 34 is the same as the direction of the magnetic lines of force of the third radial control magnetic circuit 11 in the fourth pole 34.

[0035] See also Figure 1 and Figure 3As shown, the current flow direction in the first radial winding 35 is right-in and left-out, the magnetic pole of the first pole 31 is the S pole, the current flow direction in the second radial winding 36 is left-in and right-out, the magnetic pole of the second pole 32 is the N pole, the current flow direction in the third radial winding 37 is right-in and left-out, the magnetic pole of the third pole 33 is the S pole, the current flow direction in the fourth radial winding 38 is left-in and right-out, the magnetic pole of the fourth pole 34 is the N pole, the current flow direction in the second axial winding 53 is bottom-in and top-out, and the magnetic pole of the second inner magnetic pole ring 52 is the S pole. Then, the direction of the magnetic lines of force of the second axial control magnetic circuit 13 in the second pole 32 is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 and the second radial control magnetic circuit 10 in the second pole 32, and the direction of the magnetic lines of force of the fourth axial control magnetic circuit 15 in the fourth pole 34 is the same as the direction of the magnetic lines of force of the third radial control magnetic circuit 11 in the fourth pole 34; it can also be achieved by The current flow direction is changed so that the current flow direction in the first radial winding 35 is left-in and right-out, then the magnetic pole of the first pole 31 is the N pole, the current flow direction in the second radial winding 36 is right-in and left-out, the magnetic pole of the second pole 32 is the S pole, the current flow direction in the third radial winding 37 is left-in and right-out, the magnetic pole of the third pole 33 is the N pole, the current flow direction in the fourth radial winding 38 is right-in and left-out, the magnetic pole of the fourth pole 34 is the S pole, the current flow in the second axial winding 53 is upward and downward, and the magnetic pole of the second inner magnetic pole ring 52 is the N pole. It can also be achieved that the direction of the magnetic lines of force of the second axial control magnetic circuit 13 in the second pole 32 is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 and the second radial control magnetic circuit 10 in the second pole 32, and the direction of the magnetic lines of force of the fourth axial control magnetic circuit 15 in the fourth pole 34 is the same as the direction of the magnetic lines of force of the third radial control magnetic circuit 11 in the fourth pole 34. When the direction of the magnetic lines of force of the second axial control magnetic circuit 13 in the second pole 32 is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit 9 and the second radial control magnetic circuit 10 in the second pole 32, and the direction of the magnetic lines of force of the fourth axial control magnetic circuit 15 in the fourth pole 34 is the same as the direction of the magnetic lines of force of the third radial control magnetic circuit 11 in the fourth pole 34, that is, the axial magnetic circuit will not reduce the radial magnetic circuit, then the magnetic fields of the second axial control magnetic circuit 13 and the fourth axial control magnetic circuit 15 will not affect the magnetic attraction of the second pole 32 and the fourth pole 34 to the bearing rotor 2, that is, the second axial control magnetic circuit 13 and the fourth axial control magnetic circuit 15 do not affect the radial control magnetic circuit, and each plays its own role. In summary, in the same pole unit, the magnetic pole arrangement on the four poles is SNSN, and the magnetic pole arrangement on the four poles can also be made NSNS by changing the current flow direction, and the current flow direction in the first axial winding 43 and the second axial winding 53 also needs to be adaptively changed.

[0036] As a specific implementation manner, the first axial control magnetic circuit 12 returns to the first axial stator 4 through the first inner magnetic pole ring 42-the first axial working gap 7-the bearing rotor 2-the radial working gap 6-the first pole 31-the first outer magnetic pole block 41 and is closed; the second axial control magnetic circuit 13 returns to the second axial stator 5 through the second outer magnetic pole block 51-the second pole 32-the radial working gap 6-the bearing rotor 2-the second axial working gap 8-the second inner magnetic pole ring 52 and is closed; the third axial control magnetic circuit 14 returns to the first axial stator 4 through the first inner magnetic pole ring 42-the first axial working gap 7-the bearing rotor 2-the radial working gap 6-the third pole 33-the first outer magnetic pole block 41 and is closed; the fourth axial control magnetic circuit The magnetic control circuit 15 returns to the second axial stator 5 through the second outer magnetic pole block 51-the fourth pole 34-the radial working gap 6-the bearing rotor 2-the second axial working gap 8-the second inner magnetic pole ring 52 and closes; the first radial control magnetic circuit 9 passes through the second pole 32-the radial working gap 6-the bearing rotor 2-the radial working gap 6-the first pole 31 to the radial stator 3 and closes; the second radial control magnetic circuit 10 passes through the second pole 32-the radial working gap 6-the bearing rotor 2-the radial working gap 6-the third pole 33 to the radial stator 3 and closes; the third radial control magnetic circuit 11 passes through the fourth pole 34-the radial working gap 6-the bearing rotor 2-the radial working gap 6-the third pole 33 to the radial stator 3 and closes.

[0037] As a specific implementation, in the same pole unit, the first radial winding 35 and the fourth radial winding 38 are connected in series; the second radial winding 36 and the third radial winding 37 are connected in series.

[0038] In this embodiment, since the first pole 31 and the fourth pole 34 have the same size, and the second pole 32 and the third pole 33 have the same size, when the first radial winding 35 and the fourth radial winding 38 are connected in series, and the second radial winding 36 and the third radial winding 37 are connected in series, not only can the electromagnetic forces generated by the first pole 31 and the fourth pole 34 be simultaneously adjusted by only one current, and the electromagnetic forces generated by the second pole 32 and the third pole 33 can be simultaneously adjusted by only one current, but it can also ensure that the electromagnetic forces generated by the first pole 31 and the fourth pole 34 are the same, and the electromagnetic forces generated by the second pole 32 and the third pole 33 are the same, and finally ensure that the electromagnetic resultant force generated by the four poles is along the angular bisector of the quadrant, which is more conducive to adjusting the radial position of the shaft 1. When connected in series, the winding directions of the first radial winding 35 and the fourth radial winding 38 can be opposite, and the winding directions of the second radial winding 36 and the third radial winding 37 can be opposite, so as to ensure that the polarities of the first pole 31 and the fourth pole 34 are opposite, and the polarities of the second pole 32 and the third pole 33 are opposite.

[0039] As a specific implementation, along the circumferential direction of the radial stator 3 , the width of the second pole 32 is greater than the width of the first pole 31 .

[0040] See also Figure 1 As shown, in the same pole unit, the second pole 32 and the third pole 33 are located in the middle, and the first pole 31 and the fourth pole 34 are located on both sides respectively. When the width of the second pole 32 is greater than the width of the first pole 31, that is, the second pole 32 and the third pole 33 are large teeth, and the first pole 31 and the fourth pole 34 are small teeth, this is more conducive to the optimization of the magnetic circuit and the control of the strength of the magnetic field.

[0041] Specifically, along the radial direction of the radial stator 3, the first radial winding 35, the second radial winding 36, the third radial winding 37 and the fourth radial winding 38 are all located radially outside the first outer magnetic pole block 41 and the second outer magnetic pole block 51. In this way, the first radial control magnetic circuit 9, the second radial control magnetic circuit 10 and the third radial control magnetic circuit 11 can be prevented from leaking magnetic flux in the axial direction, and the circumferential non-uniformity of the axial output can be eliminated.

[0042] like Figure 1 When it is necessary to control the shaft 1 to move to the upper left, the currents of the first radial winding 35 and the fourth radial winding 38 in the second quadrant can be increased simultaneously, or the currents of the second radial winding 36 and the third radial winding 37 in the quadrant can be increased simultaneously, or the currents of the first radial winding 35, the second radial winding 36, the third radial winding 37 and the fourth radial winding 38 in the quadrant can be increased simultaneously; when it is necessary to control the shaft 1 to move upward, the currents of the first radial winding 35 and the fourth radial winding 38 in the first and second quadrants can be increased simultaneously, or the currents of the second radial winding 36 and the third radial winding 37 in the first and second quadrants can be increased simultaneously; or the currents of the first radial winding 35, the second radial winding 36, the third radial winding 37 and the fourth radial winding 38 in the first and second quadrants can be increased simultaneously. In the radial direction, if you want to control the shaft 1 to move in other directions, you can use the above-mentioned control principle. Figure 2 When the shaft 1 needs to be controlled to move axially to the left, the current of the first axial winding 43 is increased, and the electromagnetic force to the left on the bearing rotor 2 increases. Then, the bearing rotor 2 drives the shaft 1 to move left under the action of the electromagnetic force. Figure 3 When it is necessary to control the shaft 1 to move axially to the right, the current of the second axial winding 53 is increased, and the electromagnetic force to the right on the bearing rotor 2 increases. Then, the bearing rotor 2 drives the shaft 1 to move to the right under the action of the electromagnetic force, thereby adjusting the axial position of the bearing rotor 2 by controlling the current of the first axial winding 43 and the second axial winding 53, and then adjusting the axial position of the shaft 1.

[0043] The present invention also provides a motor, comprising the above-mentioned magnetic suspension active three-degree-of-freedom bearing.

[0044] The present invention also provides a compressor, comprising the above-mentioned magnetic suspension active three-degree-of-freedom bearing.

[0045] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0046] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention, and these improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A magnetically suspended active three-degree-of-freedom bearing, characterized in that: The invention comprises a rotating shaft (1), a bearing rotor (2), a radial stator (3), a first axial stator (4) and a second axial stator (5), wherein the bearing rotor (2) is fixedly sleeved on the outer peripheral wall of the rotating shaft (1), the radial stator (3) is sleeved on the outer side of the bearing rotor (2), a radial working gap (6) is provided between the radial stator (3) and the bearing rotor (2), the first axial stator (4) and the second axial stator (5) are respectively sleeved on the outer side of the rotating shaft (1), and the first axial stator (4) and the second axial stator (5) are respectively located on both sides of the bearing rotor (2) and the radial stator (3); The radial stator (3) comprises four pole units separated by four quadrants, the pole units comprising a first pole (31), a second pole (32), a third pole (33) and a fourth pole (34) facing the inner side of the radial stator (3) and arranged in sequence, within the same quadrant, the first pole (31) and the fourth pole (34) have the same size and are symmetrical with respect to the angular bisector of the quadrant, the second pole (32) and the third pole (33) have the same size and are also symmetrical with respect to the angular bisector of the quadrant, and the first pole (31), the second pole (32), the third pole (33) and the fourth pole (34) are respectively wound with a first radial winding (35), a second radial winding (36), a third radial winding (37) and a fourth radial winding (38); The first axial stator (4) comprises a first outer magnetic pole block (41) and a first inner magnetic pole ring (42), a first axial winding (43) is arranged between the first outer magnetic pole block (41) and the first inner magnetic pole ring (42), and a first axial working gap (7) is provided between the first inner magnetic pole ring (42) and the bearing rotor (2); the second axial stator (5) comprises a second outer magnetic pole block (51) and a second inner magnetic pole ring (52), a second axial winding (53) is arranged between the second outer magnetic pole block (51) and the second inner magnetic pole ring (52), and a second axial working gap (8) is provided between the second inner magnetic pole ring (52) and the bearing rotor (2); The number of the first outer magnetic pole blocks (41) is six, and the six first outer magnetic pole blocks (41) are distributed at intervals along the circumference of the first axial stator (4). The number of the second outer magnetic pole blocks (51) is six, and the six second outer magnetic pole blocks (51) are distributed at intervals along the circumference of the second axial stator (5). In two adjacent quadrants, two adjacent first poles (31) are combined to form a first combination, and two adjacent fourth poles (34) are combined to form a second combination. The six first outer magnetic pole blocks (41) are respectively adapted to the positions of the two first combinations and the four third poles (33), and the six second outer magnetic pole blocks (51) are respectively adapted to the positions of the two second combinations and the four second poles (32).

2. The magnetically suspended active three-degree-of-freedom bearing according to claim 1, characterized in that: The first radial winding (35), the second radial winding (36), the third radial winding (37) and the fourth radial winding (38) are all energized to generate a first radial control magnetic circuit (9), a second radial control magnetic circuit (10) and a third radial control magnetic circuit (11); the first axial winding (43) is energized to generate a first axial control magnetic circuit (12) and a third axial control magnetic circuit (14); the direction of the magnetic lines of force of the first axial control magnetic circuit (12) in the first pole (31) is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit (9) in the first pole (31); the direction of the magnetic lines of force of the third axial control magnetic circuit (14) in the third pole (33) is the same as the direction of the magnetic lines of force of the second radial control magnetic circuit (10) and the third radial control magnetic circuit (11) in the third pole (33).

3. The magnetically suspended active three-degree-of-freedom bearing according to claim 2, characterized in that: The first axial control magnetic circuit (12) returns to the first axial stator (4) and is closed via the first inner magnetic pole ring (42) - the first axial working gap (7) - the bearing rotor (2) - the radial working gap (6) - the first pole (31) - the first outer magnetic pole block (41); the third axial control magnetic circuit (14) returns to the first axial stator (4) and is closed via the first inner magnetic pole ring (42) - the first axial working gap (7) - the bearing rotor (2) - the radial working gap (6) - the third pole (33) - the first outer magnetic pole block (41); the first radial control magnetic circuit (9) returns to the first axial stator (4) and is closed via the second pole ( The radial working gap (6) is connected to the first pole (31) and the radial stator (3) through the second pole (32)-the radial working gap (6)-the bearing rotor (2)-the radial working gap (6)-the third pole (33) to the radial stator (3); the radial working gap (6) is connected to the first pole (31) and the radial stator (3) through the third pole (33) and the radial stator (3) through the fourth pole (34)-the radial working gap (6)-the bearing rotor (2)-the radial working gap (6)-the third pole (33) to the radial stator (3).

4. The magnetically suspended active three-degree-of-freedom bearing according to claim 2, characterized in that: When the second axial winding (53) is energized, a second axial control magnetic circuit (13) and a fourth axial control magnetic circuit (15) are generated; the direction of the magnetic lines of force of the second axial control magnetic circuit (13) in the second pole (32) is the same as the direction of the magnetic lines of force of the first radial control magnetic circuit (9) and the second radial control magnetic circuit (10) in the second pole (32); the direction of the magnetic lines of force of the fourth axial control magnetic circuit (15) in the fourth pole (34) is the same as the direction of the magnetic lines of force of the third radial control magnetic circuit (11) in the fourth pole (34).

5. The magnetically suspended active three-degree-of-freedom bearing according to claim 4, characterized in that: The second axial control magnetic circuit (13) returns to the second axial stator (5) and is closed via the second outer magnetic pole block (51) - the second pole (32) - the radial working gap (6) - the bearing rotor (2) - the second axial working gap (8) - the second inner magnetic pole ring (52); the fourth axial control magnetic circuit (15) returns to the second axial stator (5) and is closed via the second outer magnetic pole block (51) - the fourth pole (34) - the radial working gap (6) - the bearing rotor (2) - the second axial working gap (8) - the second inner magnetic pole ring (52); the first radial control magnetic circuit (9) returns to the second axial stator (5) and is closed via the second pole ( The radial working gap (6) is connected to the first pole (31) and the radial stator (3) through the second pole (32)-the radial working gap (6)-the bearing rotor (2)-the radial working gap (6)-the third pole (33) to the radial stator (3); the radial working gap (6) is connected to the first pole (31) and the radial stator (3) through the third pole (33) and the radial stator (3) through the fourth pole (34)-the radial working gap (6)-the bearing rotor (2)-the radial working gap (6)-the third pole (33) to the radial stator (3).

6. The magnetically suspended active three-degree-of-freedom bearing according to claim 1, characterized in that: In the same pole unit, the first radial winding (35) and the fourth radial winding (38) are connected in series; and the second radial winding (36) and the third radial winding (37) are connected in series.

7. The magnetically suspended active three-degree-of-freedom bearing according to claim 1, characterized in that: Along the circumferential direction of the radial stator (3), the width of the second pole (32) is greater than the width of the first pole (31).

8. The magnetically suspended active three-degree-of-freedom bearing according to claim 1, characterized in that: Along the radial direction of the radial stator (3), the first radial winding (35), the second radial winding (36), the third radial winding (37) and the fourth radial winding (38) are all located radially outside the first outer magnetic pole block (41) and the second outer magnetic pole block (51).

9. A motor, characterized in that: A magnetically suspended active three-degree-of-freedom bearing comprising any one of claims 1 to 8.

10. A compressor, characterized in that: A magnetically suspended active three-degree-of-freedom bearing comprising any one of claims 1 to 8.

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