A hybrid superconducting magnetic bearing (SMB) system without bias current

In this paper, the properties of a hybrid superconducting magnetic bearing (SMB) system are discussed. The hybrid SMB system consists of passive SMBs, active magnetic bearings (AMBs), a rotor, and sensors. The rotor position is controlled by a controller without bias current. Because the controller does not need bias current applied to the electromagnets, energy loss is co nsidered to be less than that of other magnetic bearings. The displacements of the rotor are suppressed by both SMBs and AMBs. The superconductors of the SMBs were field-cooled. Compliance of the bearings, displacements of th e rotating rotor, and energy loss of the hybrid SMB system were investigate d. The results show that the hybrid SMB system has good performances in the se aspects.