JPH0155683B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic bearing flywheel having a jimbering mechanism used for attitude control of an artificial satellite.

Conventionally, there has been a device of this type as shown in FIG. In this figure, 1 is a rotor, 2 is rotating magnetic poles arranged at the upper and lower parts of the rotor 1,
3a and 3b are upper radial magnetic bearing cores; 4
a and 4b are the excitation coils, 3c and 3d are the lower radial magnetic bearing cores, 4c and 4d are the excitation coils, 5a and 5b are the upper and lower radial position detection pick-ups, respectively, and 6a and 6b are the upper and lower parts. Iron core for thrust magnetic bearing, 7
a and 7b are their excitation coils, 8 is a thrust position detection pick-up, 9 is the rotor of the motor, 1
0 is the motor stator, 11 is the motor coil,
12 is a wheel casing.

FIG. 2 is a diagram showing the configuration of the upper radial magnetic bearing of this device, and 13 is a position detection electric circuit;
14 is a phase compensation circuit, and 15 is a power amplifier.

Next, the operation of the radial magnetic bearing will be explained using FIG. 2. When the rotating magnetic pole 2 is displaced in the x direction, the displacement is detected as an electrical signal by the radial position detection pickup 5a and the position detection electric circuit 13. After this electrical signal is compensated by the phase compensation circuit 14, the power amplifier 1
5 to decrease the excitation current of the excitation coil 4a and increase the excitation current of the excitation coil 4b. Therefore, the electric attraction force by the radial magnetic bearing core 3a decreases, and the magnetic attraction force by the radial magnetic bearing core 3b increases.
The rotating magnetic pole 2 is returned to its original position. As described above, the rotating magnetic pole 2 is supported without contact by detecting the displacement of the rotating magnetic pole 2 with the radial position detection pick-up 5a and controlling the magnetic attraction force of the radial magnetic bearing cores 3a and 3b accordingly. Ru. Further, when a bias voltage is applied to the input terminal of the power amplifier 15 by superimposing it on the displacement signal from the radial position detection pickup 5a, the rotating magnetic pole 2 can be moved to any position in the x direction by changing the magnitude of the bias voltage. Can be stably moved to any position. The same applies to the y direction. The rotor 1 is also supported by the thrust magnetic bearing based on the same principle. That is, as shown in FIG. 1, the displacement of the rotating magnetic pole 2 in the z direction is detected by the thrust position detection pickup 8, and the excitation coil 7 is adjusted accordingly.
By controlling the currents of a and 7b, the rotor 1
is supported in the z direction without contact.

In this way, in the conventional satellite magnetic bearing flywheel, the rotor 1 is supported in a non-contact manner by one set of thrust magnetic bearings and two sets of radial magnetic bearings. The attitude angle of the satellite is controlled by changing the bias voltage of the power amplifier 15 in the up and down z-direction and the left and right x and y directions to change the inclination of the rotation axis of the rotor 1. For example, in FIG. 1, the axis of rotation of the rotor 1 can be moved from z to z' by increasing the bias voltages of the excitation coils 4a and 4d and decreasing those of the excitation coils 4b and 4c.

However, conventional magnetic bearing flywheels for satellites require 5 sets of control devices and 10 electromagnets to control rotor displacement in a total of 5 directions: the z-direction of the thrust, and the x and y directions of the upper and lower radials. Therefore, the wheel configuration is complicated and expensive, and reliability is significantly reduced.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional ones.The two magnetic bearings, the thrust magnetic bearing and the radial magnetic bearing, are replaced with a pivot bearing, and the contact pressure of the pivot bearing part is reduced by a permanent magnet. The purpose of the present invention is to provide a magnetic flywheel for an artificial satellite that can simplify the bearing configuration by generating an attractive force of . This invention will be explained below.

FIG. 3 is a sectional view showing an embodiment of the present invention.
16 is a pivot bearing, and 17 is a permanent magnet. That is, since there is no gravity in outer space, the contact pressure of the pivot bearing portion is provided by the attractive force between the permanent magnet 17 and the rotating magnetic pole 2. In addition, by changing the bias voltage of the power amplifier 15 in the x and y directions of the upper radial magnetic bearing, the rotation axis of the rotor 1 can be tilted using the pivot bearing 16 as a fulcrum, and the satellite can be controlled in its attitude angle. Necessary gimbaling movements can be performed.

As explained above, in this invention, a pivot bearing and a permanent magnet with no control of attraction force are arranged at one end of the rotating shaft, and a radial magnetic bearing is arranged at the other end of the rotating shaft, so that the gimbaling effect can be minimized by minimizing the electromagnetic magnet. It can be composed of In addition, since the permanent magnet applies appropriate pressure to the contact part of the pivot bearing by magnetic attraction, the action of the pivot bearing is effective even in zero gravity in space, and therefore, it works in cooperation with the radial magnetic bearing. The gimbaling effect is not lost.

In this manner, the present invention has the advantage that the device is inexpensive and highly reliable.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional magnetic flywheel for an artificial satellite, Fig. 2 is a schematic diagram for explaining the structure and operation of the upper radial magnetic bearing of a conventional magnetic bearing flywheel for an artificial satellite, and Fig. 3 is a schematic diagram for explaining the structure and operation of the upper radial magnetic bearing of the conventional magnetic bearing flywheel for an artificial satellite. FIG. 1 is a sectional view showing an embodiment of the present invention. In the figure, 1 is the rotor, 2 is the rotating magnetic pole, 3a, 3b
1 is an iron core for a radial magnetic bearing, 4a and 4b are excitation coils, and 5a and 5b are pickups for detecting displacement in the radial direction. 6a and 6b are iron cores for thrust magnetic bearings, 7a and 7b are excitation coils, 8 is a pick-up for thrust position detection, 9 is a motor rotor, and 10
is the motor stator, 11 is the motor coil, 1
2 is a casing, 13 is a position detection electric circuit, 1
4 is a phase compensation circuit, 15 is a power amplifier, 16 is a pivot bearing, and 17 is a permanent magnet. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. In a magnetic bearing flywheel that controls the attitude angle of an artificial satellite by controlling the inclination of the rotational axis of the rotor, a pivot bearing that has a mechanical contact portion at one end of the rotational shaft, and a pivot bearing that is suitable for the contact portion of the pivot bearing. a permanent magnet whose attraction force is not controlled to apply a magnetic attraction force; 1. A magnetic bearing flywheel for an artificial satellite, comprising a radial magnetic bearing that supports the shaft end at any position within a plane orthogonal to the rotational axis by controlling force.