JPH0783230A - Magnetic bearing - Google Patents

Abstract

PURPOSE:To change force capable of being generated by same bearing, so as to obtain a bearing suitable for applications by dividing a coil into a plurality of parts or a plurality of groups and changing the number of coils to be connected as needed. CONSTITUTION:A coil incorporated in a magnetic bearing main body 1 is divided into a plurality of parts 2a, 2b, 2c and manufactured. The total number of windings of the coil in which electric current is allowed to flow is changed by dividing and incorporated the coil and changing the connecting method of the coil as needed, and force to be generated by a magnetic bearing main body 1 is can be changed. Accordingly, several kinds of bearing main bodies can be supplied by one kind of bearing main body, thereby design costs and manufacturing costs of the bearing can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a bearing for instructing a force in a direction perpendicular to the axis of a rotor of a rotary machine such as a centrifugal compressor / pump or an axial force generated in a rotary machine. Bearings that utilize

[0002]

2. Description of the Related Art As described above, in a conventional magnetic bearing, one coil generates both static force and dynamic force. However, the required static force and dynamic force are different depending on the applied machine. Therefore, in order to supply a magnetic bearing that can generate an appropriate force, the number of turns of the coil is changed and the size of the bearing is changed.
Therefore, it has been necessary to manufacture and support many types of bearings.

In order to manufacture many types of bearings, many manufacturing drawings must be made correspondingly, and many jigs and tools to be used at the time of manufacturing must be made.

[0004]

In the conventional magnetic bearing,
Since the coil for controlling the force in one direction was composed of one or one group, it was necessary to manufacture another bearing in order to change the force required for the bearing. Therefore, many types of bearings had to be manufactured in order to supply proper bearings that meet the required specifications.

If the number of types to be manufactured is reduced, it may be used in an over-specification situation, in which case magnetic saturation may occur and it may not be possible to secure the necessary force.

[0006]

[Means for Solving the Problems] To change the force of a magnetic bearing, (a) change the current supplied to the magnetic bearing (change the capacity of the power amplifier).

(B) The area of the magnetic bearing is changed.

(C) The number of turns of the coil is changed.

A method is conceivable. Of these, the problem was dealt with by making it possible to change the number of turns of the coil in (3) as needed.

A bearing is manufactured by dividing it into a plurality of coils in advance, and the combination of coils to be connected is changed and used as necessary.

[0011]

[Operation] The coil is divided into a plurality of or a plurality of groups,
By changing the number of coils to connect as needed,
The force that can be generated by the same bearing can be changed, and a bearing that suits the purpose of use can be provided. Since bearings that meet the required specifications can be used, insufficient power due to over-specification will not occur.

Since a plurality of pairs of magnetic poles are often provided for one control shaft, by dividing the number of turns of the coil in the same coil slot into a plurality of turns, The force of the magnetic bearing can be changed without changing the force ratio.

By changing the number of turns of the coil divided into a plurality of types, it is possible to increase the kinds of forces that the bearing can produce by combining the divided coils, and to make a detailed response.

[0014]

1 is a sectional view of a magnetic bearing of the present invention.

In the present embodiment, an example in which the coil incorporated in each coil slot is divided into three (2a, 2b, 2c) is shown.

In the magnetic bearing, the displacement of the shaft is detected by the position sensor 6 and the signal is input to the control loop 5. The control loop 5 calculates the deviation from the reference position to obtain the amount required for correction. Based on the amount required for this correction, the power amplifier 4 supplies a current to the coil 2 to generate the force required in the magnetic bearing body 1.

The force required for the magnetic bearing body is obtained as the sum of the static force and the dynamic force, but the magnitude differs depending on the application target. An appropriate magnetic bearing main body that meets the required specifications is required in order to prevent troubles such as over-spec causing magnetic saturation and making it impossible to generate the necessary force.

Therefore, the coil incorporated in the magnetic bearing body 1 is divided into a plurality of coils 2a, 2b, 2c and manufactured.
Considering the case where one control shaft is composed of a plurality of pairs of magnetic poles, this example shows the case where the coil 2 in the coil slot is divided into 2a, 2b, and 2c. It is also possible to divide the coil 2 into two or four or more depending on the total number of turns. Further, although each coil slot is constituted by one coil, it is possible to consider the coils having a plurality of magnetic poles as separate coils.

By dividing and assembling the coil 2 in this manner, the total number of turns of the coil through which the current flows can be changed by changing the coil connection method as needed (see FIGS. 1 and 2). It is possible to change the force generated by the magnetic bearing body. Therefore, one type of bearing body can supply several types of bearing bodies, and the bearing design cost and manufacturing cost can be reduced.

[0020]

EFFECTS OF THE INVENTION With the same magnetic bearing, different magnetic bearings can be supplied. In other words, one type of magnetic bearing can supply several types of magnetic bearings having appropriate specifications, and it is possible to reduce design costs, manufacturing drawings, and jig / tool costs necessary for manufacturing.

By dividing the coil in the same coil slot, the force of the magnetic bearing can be changed without changing the ratio of the forces between the plurality of magnetic poles, so that the characteristics of the bearing do not change.

By changing the number of turns of the coil to be divided, it is possible to increase the kinds of force that the magnetic bearing can output, and it is possible to supply a more appropriate bearing.

[Brief description of drawings]

FIG. 1 is a block diagram of a magnetic bearing of the present invention.

FIG. 2 is a block diagram of a conventional magnetic bearing.

FIG. 3 is a block diagram of a magnetic bearing of the present invention.

[Explanation of symbols]

1 ... Magnetic bearing modification, 2 ... Coil, 3 ... Core, 4 ... Power amplifier, 5 ... Control loop, 6 ... Position sensor.

Claims (1)

[Claims] 1. A coil for applying an electric current to generate a magnetic field,
A magnetic bearing comprising a core portion that forms a magnetic loop between the coil and a rotor, wherein the number of coils to be connected is changed according to need by dividing the coil into a plurality of parts.