| 摘要 |
PURPOSE:To stably stop a rotary electric machine by a method wherein, when the axial deflection amount of the rotary electric machine becomes larger than a threshold value, a switch operating device opens a switch, a current flowing to the rotary electric machine, a radial magnetic bearing and a thrust magnetic bearing is cut off and the rotary electric machine is touched down. CONSTITUTION:While a motor 2 is being operated, a shaft 1 is supported in a noncontact manner so as to be freely rotatable by radial magnetic bearings 4, 4 at both end parts and by a thrust magnetic bearing 6. The displacement of the magnetic bearings 4, 4, 6 is detected by sensors 5, 5, 7. When the output of the sensors 5, 5, 7 exceeds a threshold value by an external force or for some reason, a control device 8 opens a switch S1 via a switch operating device 10, the exciting current of the magnetic bearings 4, 4, 6 is cut off, a switch S2 is opened, and the driving current of the motor 2 is cut off. The shaft 1 is supported by touchdown bearings 9 at both ends and stopped. Thereby, it is possible to prevent the shaft from being damaged when it comes into contact with a fixation-side member. |
