Calculation of Levitation Force Using a Critical-State Model

The interaction forces between a permanent disk and a superconductor disk are calculated for a cylindrical system by using the Anderson–Kim model. Model calculations show that both the vertical force and the stability exhibit a peak-like behavior in the repulsive branch. These peaks in the calculations are dependent on the model parameter and the ratio between the penetration and the applied fields, H _p/H _m. The features of hysteretic force and magnetic stiffness are discussed.