Permanent-magnetic biased axial magnetic bearing
Technical field
What the present invention relates to is a kind of hybrid magnetic bearing of magnetic bearing technical field, in particular a kind of permanent-magnetic biased axial magnetic bearing.
Background technique
Magnetic suspension bearing abbreviates magnetic bearing again as, is to utilize the magnetic force between stator and the rotor that rotor is suspended in the space, makes a kind of novel high-performance bearing that does not have Mechanical Contact between stator and the rotor.Owing to there is not contact mechanically between the stator and rotor, so the rotor of magnetic suspension bearing can reach very high running rotating speed, and have advantages such as mechanical wear is little, energy consumption is low, the life-span is long, unlubricated, pollution-free, be particularly suitable for special applications such as high speed, vacuum and super cleaning.
At present, the mode that magnetic bearing provides according to magnetic force is divided into following several: first kind is active magnetic bearings, there is bias current in this magnetic bearing coil, so that bias magnetic field to be provided, superpose with the biasing magnetic flux by the control electric current control magnetic flux that the control winding produces of flowing through, thereby produce controlled suspending power, volume, weight and power consumption are all bigger.Second kind is passive magnetic bearing, the suspending power of this magnetic bearing is provided by permanent magnet fully, and its required controller is simple, and the suspension power consumption is little, but rigidity and damping are all less, only generally apply in one direction supporting object or alleviate the load that acts on the traditional bearing.The third is a hybrid magnetic bearing, the electromagnet that this magnetic bearing adopts permanent-magnet material to substitute in the active magnetic bearings produces bias magnetic field, the just balanced load that electromagnet provides or the controlling magnetic field of interference, greatly reduce the power loss that produces because of bias current, the required Number of ampere turns of electromagnet is half of active magnetic bearings, dwindle the volume of magnetic bearing, alleviated its weight, and improved bearing capacity.
The permanent-magnetic biased axial magnetic bearing structural type of research is divided into three kinds in the world at present, and a kind of is that permanent magnet is placed rotor, and installation difficulty is increased, and limits its high speed operation; Second kind of magnetic bearing places the both sides of stator with suspended rotor, and axial length is long, and critical speed of rotation is low; In the third magnetic bearing axially the control magnetic flux pass permanent magnet, permanent magnet is tangible demagnetizing effect, leakage field is bigger, at a high speed, the application is restricted efficiently.
Summary of the invention
Goal of the invention: the objective of the invention is to overcome the deficiencies in the prior art, a kind of permanent-magnetic biased axial magnetic bearing is provided, its structure is comparatively simple, control is convenient, by rotor core being designed to laminar disc, the critical speed of rotation height can produce a stable driven suspension power, use it in the energy accumulation device for fly wheel of vertical placement, can significantly reduce the suspension power consumption of magnetic bearing.
Technological scheme: the present invention is achieved by the following technical solutions, the present invention includes stator module and rotor assembly, described stator module comprises axial stator, axially controls winding, permanent magnet and radial stator, described rotor assembly comprises rotating shaft and rotor core, wherein: axially control on the magnetic pole that winding is around in axial stator, rotor core is set in the rotating shaft, radial stator is located in the axial stator, permanent magnet be attached at radial stator the outer end and and the interior edge face of axial stator contact, the inside of axial stator and radial stator is located in rotor core; Described rotor core is a disc, and the central sleeve of disk is connected in the rotating shaft, and radial stator is located at the two ends of disk, and axial stator is located at the outer end of disk, and the length that described rotor core is socketed on the length of part of rotating shaft and rotating shaft is identical.
Described radial stator only is used for stream with the biasing magnetic flux, and for ease of the high speed rotating of suspended rotor, described rotor core and radial stator are that solid soft magnetic material is made.
When the present invention works: permanent-magnetic biased axial magnetic bearing of the present invention, utilization is positioned at the annular permanent magnet of two identical radial magnetizings of rotor core both sides and sets up quiescent biasing magnetic field, form closed magnetic circuit by axial stator, rotor core and radial stator, when rotor core is positioned at the longitudinal balance position, because the symmetry properties of structure, the magnetic flux that annular permanent magnet produces equates that at the right side of the axial end of rotor core air gap and the left side air gap place this moment, left and right sides suction equated; Suppose that this moment, rotor was subjected to level disturbing force left, then axially controlling winding passes to the control electric current and produces the control magnetic flux superpose with the biasing magnetic flux in axial air-gap, magnetic field strengthens in the right air gap, controlling magnetic field is opposite with the bias magnetic field direction in the air gap of a left side, field weakening, generation level suspending power to the right in rotor core; If rotor is subjected to disturbing force to the right, then control current reversal, the control flux-reversal of formation and the stack of biasing magnetic flux form suspending power left; As its axial air-gap is designed to dissymmetrical structure, then can produce a stable static suspension power, use it in the flywheel gear of vertical placement, can significantly reduce the power consumption of bearing.
Beneficial effect: radial stator only is used for stream with the biasing magnetic flux among the present invention, is solid disk, has greatly simplified the structure of magnetic bearing.Rotor core mainly in order to stream with biased magnetic bearing, this discoid rotor core has not only shortened dramatically the axial length of magnetic bearing, improved the critical speed of rotation of rotor, simultaneously, also shorten the magnetic circuit of axial control magnetic flux, reduced the loss of axial magnetic flux.The magnetic pole of axial stator is positioned on the radial stator, has not only shortened the axial length of whole bearing, and axial control magnetic flux and magnetic circuit are not radially disturbed mutually, does not produce the magnetic circuit coupling.Simultaneously, this magnetic bearing utilizes permanent magnet to produce the biasing magnetic flux, it is little also to have power consumption, the advantage that axial length is short, have broad application prospects in high speed applications such as flywheel energy storage, air condition compressor, turbomolecular pumps, national defence fields such as Aero-Space and naval vessels that it is used in then have more significance.As its axial air-gap is designed to dissymmetrical structure, then can produce a stable static suspension power, use it in the flywheel gear of vertical placement, can significantly reduce the power consumption of bearing.
Description of drawings
Fig. 1 is a structural representation of the present invention;
Fig. 2 is a magnetic circuit schematic diagram of the present invention.
Embodiment
Below embodiments of the invention are elaborated, present embodiment is being to implement under the prerequisite with the technical solution of the present invention, provided detailed mode of execution and concrete operating process, but protection scope of the present invention is not limited to following embodiment.
As shown in Figure 1, present embodiment comprises stator module and rotor assembly, and wherein: stator module is located at the periphery of rotor assembly.Described stator module comprises axial stator 1, axially controls winding 2, permanent magnet 3 and radial stator 4, described rotor assembly comprises rotor core 5 and rotating shaft 6, it is characterized in that: axially control on the magnetic pole that winding 2 is around in axial stator 1, rotor core 5 is set in the rotating shaft 6, radial stator 4 is located in the axial stator 1, permanent magnet 3 be attached at radial stator 4 the outer end and and the interior edge face of axial stator 1 contact, the inside of axial stator 1 and radial stator 4 is located in rotor core 5; Described rotor core 5 is discs, and the central sleeve of disk is connected in the rotating shaft 6, and radial stator 4 is located at the two ends of disk, and axial stator 1 is located at the outer end of disk, and the length of part that described rotor core 5 is socketed on rotating shaft 6 is identical with the length of rotating shaft 6.
Described radial stator 4 is two solid disks, be located at the two ends of rotor core 5 respectively, the interior edge face of described axial stator 1 and annular permanent magnet 3 contact, the annular permanent magnet 3 of radial magnetizing adopts neodymium iron boron to make, be attached at the outer end of two radial stators 4 respectively, two radial stators 4 are identical, only are used for stream with the biasing magnetic flux, also make discoid with solid soft magnetic material.High speed rotating for ease of suspended rotor, rotor core 5 also adopts solid soft magnetic material to make, be sleeved in the rotating shaft 6, form axial air-gap with axial stator 1, form radial air gap with radial stator 4, be arranged in axial stator 1 magnetic pole rotor core 5 mainly in order to stream with biased magnetic bearing, can be made into the sheet discs shape, this discoid rotor core 5, not only shorten dramatically the axial length of magnetic bearing, improved the critical speed of rotation of rotor, simultaneously, also shorten the magnetic circuit of axial control magnetic flux, reduced the loss of axial magnetic flux.The magnetic pole of axial stator 1 is positioned on the radial stator 4, has not only shortened the axial length of whole bearing, and axial control magnetic flux and magnetic circuit are not radially disturbed mutually, does not produce the magnetic circuit coupling.As its axial air-gap is the asymmetric layout in the left and right sides, then can produce a stable driven suspension power.
Shown in solid line among Fig. 2, annular permanent magnet 3 produces the biasing magnetic flux, through magnetic pole, axial air-gap, rotor core 5, radial air gap and the radial stator 4 formation closed magnetic circuits of axial stator 1; As shown in phantom in Figure 2, axially control magnetic flux and form the closed-loop path in magnetic pole, axial air-gap, the rotor core 5 of axial stator 1.