| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic bearing system with capability to control stably the magnetic bearing irrespective of variation in gaps between a sensor and a rotating body due to change in temperature of the rotating body. SOLUTION: The rotating body 11 is supported in a contact-free manner by attraction of magnets 12, 13 and gaps d<SB>1</SB>, d<SB>2</SB>between the magnets 12, 13 and the rotating body are detected by position sensors 14, 15, whose outputs are applied to a subtracting device 21 for performing subtraction, the result is multiplied by a control gain in a control constant regulating circuit 23 and then feedback is performed through a PID regulator 25 to the magnets 12, 13. Thereby, the rotating body 11 is supported at an optimum floating position with the gaps kept uniform between the magnets 12, 13 and the rotating body. Furthermore, variation in detection sensitivity of sensors 14, 15 due to thermal expansion or shrinkage of the rotating body 11 is compensated by performing addition of output of the sensors 14, 15 to generate a control gain corresponding to the additional value in the control constant regulating circuit 23. Consequently, stable bearing control can be carried out over a wide range of temperature of the rotating body. COPYRIGHT: (C)2003,JPO
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