Analytical field computation of a tubular permanent-magnet linear motor

This paper deals with a tubular slotless linear motor with surface-mounted permanent magnets (PMs). The magnetic field strength and flux density due to the PMs are analytically computed by applying Maxwell's equations. The field problem is solved by introducing a convenient approximation in the PM magnetization, without loss of accuracy in the final solution. The agreement of the analytical results with those obtained by the finite-element method shows the proposed field computation particularly suitable for implemention in motor design software, for a fast analysis of the PM linear motor.