Levitation of Conductive and Magnetically Anisotropic Ball

This paper presents the analytical solution of levitation problem for both magnetically anisotropic and conductive balls. The magnetic field exerts eddy currents in magnetic and conductive balls. The forces, both Lorentz (of eddy current) and material (caused by inhomogeneity of reluctivity), lead to the levitation of the ball. The electromagnetic field is determined by means of variable separation method. The forces, both Lorentz and material acting upon the ball, are calculated. Power losses are calculated twice by means of Joule volume integral and Poynting surface integral. The total force is evaluated three times by Maxwell, coenergy, and Lorentz methods. Levitation force and power losses versus frequency are presented. Asymptotic relations for levitation force and power losses are derived. The comparison to levitating disk at the same volume is presented.