CONTROL DEVICE FOR VACUUM POUMP

摘要

PROBLEM TO BE SOLVED: To provide a control device to settle abnormal whirling of a rotor during rush in the atmosphere in a short time. SOLUTION: A control device 4 for a vacuum pump 1 to perform feedback control of a magnetic bearing device based on a position signal from a position sensor 1b comprises a current amplifier 41 to feed an exciting current to the electromagnet 1a of the magnetic bearing device; a first compensator 42 to control the current amplifier 41; a second compensator 43 having frequency characteristics different from those of the first compensator 42; a switching apparatus 46 to input a position signal by switching a position signal from a position sensor 1b to either the first comprensator 42 or the second compensator 43; and a state discriminator 44 to drive the switching apparatus 46 based on the state of the vacuum device 2 on which a vacuum pump 1 is mounted. A chamber pressure signal from a pressure gauge 7 and a valve opening signal from the control device 3 for the vacuum device are used as a state signal inputted to the state discriminator 44 to discriminate switching the compensator.