Patent ID: 7091641

Claim:
A magnetic bearing device comprising: a rotor; position control means for controlling at least one of a radial position and an axial position of the rotor by electromagnets; first voltage generating means for generating a first voltage between a first positive electrode and a negative electrode; second voltage generating/maintaining means for generating a second voltage, which is lower than the first voltage, between a second positive electrode and the negative electrode and maintaining the second voltage, the first and second positive electrodes being different from each other; and first excitation control means for exciting and controlling the electromagnets by one of a first supply current supplied from the second positive electrode to the negative electrode and a first regenerated current regenerated from the second positive electrode to the first positive electrode, wherein the first excitation control means includes: a first switch element for connecting and disconnecting the first supply current; a first control circuit for controlling connection and disconnection of the first switch element; and a first rectifier element for causing the first regenerated current to flow in the direction of its regeneration.