A magnetic bearing control device includes a rotation speed sensor for
detecting a rotational speed of a rotating member supported on an axial
magnetic bearing and a radial magnetic bearing without contact, and a
displacement sensor for detecting an axial displacement of the rotating
member. A control unit outputs a control signal of the axial magnetic
bearing based on a signal from the displacement sensor. A filter unit
reduces a signal with a specific frequency from the control signal output
from the control unit, and passes a remaining signal, and a driving unit
drives the axial magnetic bearing based on the signal output from the
filter unit. The filter unit includes several notch filters with
different ranges of the specific frequencies, and a selection device for
selecting at least one of the notch filters according to the rotational
speed.