Magnetic bearing apparatus
First Claim
1. A magnetic bearing apparatus comprising:
- a rotor;
a motor having stator coils for generating a rotary magnetic field for rotating the rotor;
magnetic supporting coils for producing a magnetic force for magnetically supporting the rotor in a radial direction thereof;
a radial position sensor for detecting movement of the rotor in the radial direction thereof in the vicinity of the radial posistion sensor;
composite magnetic force inferring means for inferring composite vectors of the magnetic force affecting the rotor based on the rotary magnetic field and the radial position of the rotor; and
magnetic support adjustment means for adjusting the magnetic force produced by the magnetic supporting coils to cancel the composite vectors of the magnetic force in the motor.
2 Assignments
0 Petitions
Accused Products
Abstract
To reduce vibration caused by an unbalance of magnetic force generated in a motor portion due to run-out of a rotor in a magnetic bearing apparatus having the motor portion. The vibration of the rotor is detected by means of a radial direction sensor mounted for controlling a magnetic bearing. Then, the vibration in the motor portion is inferred from the run-out of the rotor detected by the radial direction sensor by using the geometric positional relationship between the rotor and the radial direction sensor. The relationship between the unbalance amount of the magnetic force and the amount of run-out of the rotor in the motor portion is formed into the database through experiments or simulation in advance, and the unbalance amount of magnetic force is obtained from this database. Then, the magnetic force resisting the unbalance amount of this magnetic force is generated to offset this unbalance amount.
22 Citations
14 Claims
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1. A magnetic bearing apparatus comprising:
- a rotor;
a motor having stator coils for generating a rotary magnetic field for rotating the rotor;
magnetic supporting coils for producing a magnetic force for magnetically supporting the rotor in a radial direction thereof;
a radial position sensor for detecting movement of the rotor in the radial direction thereof in the vicinity of the radial posistion sensor;
composite magnetic force inferring means for inferring composite vectors of the magnetic force affecting the rotor based on the rotary magnetic field and the radial position of the rotor; and
magnetic support adjustment means for adjusting the magnetic force produced by the magnetic supporting coils to cancel the composite vectors of the magnetic force in the motor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
- a rotor;
-
9. A magnetic bearing apparatus comprising:
- a rotor;
a motor having stator coils for generating a rotary magnetic field for rotating the rotor;
magnetic supporting coils for producing a magnetic force for magnetically supporting the rotor in a radial direction thereof;
a radial position sensor for detecting radial movement of the rotor in the vicinity of the radial position sensor;
composite magnetic force determining means for determining composite vectors of a magnetic force affecting the rotor based on the rotary magnetic field and the radial position of the rotor; and
magnetic support adjusting means for adjusting the magnetic force produced by the magnetic supporting coils to cancel unbalance in the magnetic force affecting the rotor and represented by the composite vectors of the magnetic force, to thereby reduce vibration of the rotor. - View Dependent Claims (12, 13, 14)
- a rotor;
-
10. A magnetic bearing apparatus according to clam 9;
- wherein the composite magnetic force determining means comprises a magnetic flux detector for detecting a magnetic flux in an air gap between a magnetic pole of the motor and the stator coils, and means for determining the composite vectors of the magnetic force affecting the rotor based upon the magnetic flux detected by the magnetic flux detector.
- View Dependent Claims (11)
Specification