Low watt consumption permanent magnet offset external rotor hybrid radial magnetic bearing

Abstract

The permanent-magnet offset outer rotor mixed radial magnetic bearing with low power consumption is composed of rotor iron core. Permanent-magnets, stator iron cores and excitation coils. Said invention also provides ther arrangement mode, between outer surface of stator iron core and inner surface of rotor iron core a certain gap is remained to form air gap, between two stator iron cores and permanent magnet a second air gap is formed. The permanent magnet utilizes stator iron core magnet poles to form offset magnetic field on X and Y directions.

Description

Technical field [0001] The invention relates to a non-contact magnetic suspension bearing, in particular to a small-volume, low-power-consumption permanent-magnet-biased outer-rotor radial magnetic bearing, which can be used as a non-contact support for rotating parts in spacecraft such as satellites. Background technique [0002] Magnetic suspension bearings are divided into pure electromagnetic bearings and hybrid magnetic suspension bearings with permanent magnetic bias and electromagnetic control. The former uses large current and consumes a lot of power, and the hybrid magnetic suspension bearings with permanent magnetic bias and electromagnetic control. The magnetic field generated by the permanent magnet bears the main load. Bearing capacity, the electromagnetic field provides auxiliary adjustment bearing capacity, so this kind of bearing can greatly reduce the control current and reduce the loss. However, some of the current permanent magnet bias outer rotor radial m...

AI Technical Summary

Problems solved by technology

However, some of the current permanent magnet bias outer rotor radial magnetic bearing structures are based on ordinary radial electromagnetic bearings, and permanent magnets are placed upward on the electromagnetic magnetic circuit, so that the magnetic flux generated by the control coil must pass through the permanent magnets. Due to the large reluctance of the permanent magnet, a large excitation current is required for the control coil to generate a certain electromagnetic flux, which will obviously increase the power consumption of the bearing; some structures directly connect the permanent magnet to the stator laminated core, so that the permanent magnet When the magnetic circuit passes through the stator core vertically, it will lose too much magnetomotive force, which will greatly weaken the attraction force of the permanent magnet to the rotor shaft; there are also some structures that connect the permanent magnet with the laminated core through the magnetic ring, and the electric excitation The magnetic circuit forms a loop through the laminated iron core, so that the permanent magnetomotive force will not be lost in the laminated iron core, and the electric excitation magnetic circuit will not pass through the permanent magnet itself, but the radial magnetic bearing of this structure has its permanent magnet The plane where the magnetic circuit is located and the plane where the electric excitation magnetic circuit is located are perpendicular to each other, which will result in a longer axial length, so it cannot meet the small size and light weight requirements of spacecraft such as satellites and space stations.

Chinese patent application 200510086223.5, such as figure 1 As shown, Chinese patent application 200510086213.1, such as figure 2 As shown, two kinds of outer rotor radial magnetic bearings are given. Although the permanent magnet magnetic circuit of these two structures is coplanar with the electric excitation magnetic circuit, the axial length can be shortened, but the stator core magnetic poles have 8 uniform poles. Distributed on the circumference, the force in the X and Y directions of the magnetic bearing is composed of the resultant force of these 8 magnetic poles. Since the 8 stator magnetic poles are separated by 45 degrees in turn, they are generated in the directions of +X, -X, +Y and -Y A certain bearing capacity requires a large current to be passed into each stator pole coil, thus resulting in increased power consumption

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