Effect of Axial Segmentation of Permanent Magnets on Rotor Loss in Modular Permanent-Magnet Brushless Machines

Abstract

This paper presents a computationally efficient technique in determining the influence of the finite axial length of the permanent magnets on the rotor eddy-current loss in modular brushless ac machines. The technique is employed to quantify the effectiveness of axially segmenting the permanent magnets of four-phase, eight-slot, ten-pole and five-phase, ten-slot, 12-pole brushless machines, which have been designed to meet the performance requirements of an electromechanical flight control surface actuator for a "more-electric" aircraft.