Analysis of unbalanced force for high-speed slotless permanent magnet machine with Halbach array

This paper reports on the comparison of two types of high-speed slotless permanent magnet machines with the rotor eccentricity as the motor/generator for an electromechanical battery. Using a two-dimensional finite-element method, this paper deals with the magneto static field and unbalanced forces. Specifically, the advantages of Halbach array are discussed when the rotor has eccentricity.