Experimental Verification of an Axially-Differential Magnetic-Geared Motor

Abstract

　Magnetic geared motors attract attention due to its low-speed and high-torque characteristics and contactless torque transmission. However, the gear ratio is at most 10 because it depends on the pole-pair ratio between rotors, and the increase of the number of pole pairs decreases the torque density. In order to solve this problem, an axially-differential magnetic-geared motor that is axially combined a magnetic geared motor with a magnetic gear has been proposed. It can increase the gear ratio up to approximately several hundred without the increase of the number of pole pairs. In this paper, the performance of the axially-differential magnetic-geared motor is investigated by carrying out measurements on a prototype and 2-D finite element analysis.