A Rotary Modulation Double Coil Axial Spherical Pure Electromagnetic Bearing

Abstract

The invention discloses a double-coil axial spherical pure electromagnetic magnetic bearing with rotation and modulation effects. The double-coil axial spherical pure electromagnetic magnetic bearing comprises an upper stator iron core, a lower stator iron core, an upper axial upper end excitation coil, an upper axial lower end excitation coil, a lower axial upper end excitation coil, a lower axial lower end excitation coil, a rotor, an upper axial air gap, a lower axial air gap, a stator mounting disc, a rotation and modulation rotor bearing sleeve, a rotation and modulation bearing, a rotation and modulation rotor lock nut, an ultrasonic motor stator, an ultrasonic motor stator, a rotation and modulation stator bearing sleeve and a rotation and modulation stator lock nut. The upper and lower stator iron cores adopt a pole shoe structure; the excitation coils of the upper and lower stator iron cores adopt a double-coil structure, and the number of turns of one coil is different from that of turns of the other coil; the current of the small number of turns of the coil is controlled while the current of the large number of turns of the coil is constant, and the current response rate is high. A stator of the double-coil axial spherical pure electromagnetic magnetic bearing is driven by an ultrasonic motor, and the double-coil axial spherical pure electromagnetic magnetic bearing has rotation and modulation effects, so that gyro drift caused by rotation and introduction of gyrorotor can be eliminated, and the detection accuracy of the magnetic bearing during detection of angular velocity can be improved.

Description

technical field [0001] The invention relates to a non-contact axial magnetic suspension bearing, especially a double-coil axial spherical pure electromagnetic bearing with rotation modulation function, which can be used as a non-contact support for rotating parts in small spacecraft, and is especially suitable for magnetic suspension sensitive bearings. Non-contact support for gyroscopes. technical background [0002] With the development of aerospace technology, satellites, space stations and other spacecraft have higher and higher requirements for attitude control accuracy, and traditional mechanical momentum wheels can no longer meet the requirements. The magnetic levitation flywheel is supported by magnetic bearings, which eliminates the wear caused by mechanical bearings and improves the accuracy and stability of torque control. [0003] In the existing magnetic levitation flywheel structure, a single-degree-of-freedom axial magnetic bearing or a three-degree-of-freedo...

AI Technical Summary

Problems solved by technology

However, when the rotor deflects, the magnetic air gap between the stator and rotor of the magnetic bearing is uneven, resulting in uneven electromagnetic force in the magnetic pole surface, thereby generating a torsional moment relative to the center of mass of the rotor, that is, the translation control produces an interference torque to the torsion control

The magnetic pole surfaces of the permanent magnet bias axial magnetic bearings described in Chinese patent application numbers 200510011272.2 and 200710098749.4 are all cylindrical. When the magnetic bearing deflects, there is an uneven air gap between the stator and the rotor, resulting in a large torsional negative torque. , which increases the load on the torsional bearing of the flywheel, thereby reducing the control precision and control torque precision of the flywheel rotor

In addition, if the existing magnetic levitation flywheel or magnetic levitation gyro is to realize its detection function as a sensitive component, it is often limited by the environmental disturbance torque, which leads to the reduction of the accuracy of the detection component.

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