Research on a Superconducting Magnetic Bearing System for Submerged Cryogenic Disk Motor-Pump

Abstract

There are some disadvantages in conventional cryogenic liquid pumps (CLPs) with mechanical bearings, such as difficult lubrication and short working life. In this paper, we propose a new structure of CLP-submerged cryogenic disk motor-pump with superconducting magnetic bearing (SMB). The impeller and the rotor of the disk motor are combined as the suspension rotor of the disk motor-pump. The suspension rotor which is supported by SMB system, rotates frictionlessly with self-stabilized. The SMB system includes a radial-type SMB, an axial-type permanent magnet bearing, and an axial flux disk motor. Theoretical calculations and experimental measurements of levitation forces in the SMB system are carried out. The levitation force of radial-type SMB is calculated by using H -formulation finite-element model in COMSOL. The kinetic model of the suspension rotor is established to ensure the force balance and torque balance. The results demonstrate the feasibility of the proposed submerged cryogenic disk motor-pump with SMB.