Analysis of the tubular motor with Halbach and radial magnet array

In the machine tool industry, direct drive linear motor technology is of increasing interest as a means to achieve high acceleration, and to increase reliability. This paper analyzes and compares the characteristics of tubular motor with Halbach and radial magnet array respectively. The governing equations established analytically in terms of vector potential, two dimensional cylindrical coordinate system and Maxwell´s equations. We derive magnetic field solutions due to the PMs and to the currents. Motor thrust, flux linkage, back emf are then derived. The results are shown in good conformity with those obtained from the commonly used finite element method.