Recent developments and comparative study of magnetically geared machines

This paper overviews the recent developments and various topologies of magnetically geared (MGd) machines. Particularly, current design trends and research hotspots of this kind of MGd machines are emphasized, with the aid of statistic summary of the published papers. According to different evolutions from a magnetic gear (MG), four mainstreams of MGd machines are extracted and compared in terms of both mechanical complexity and electromagnetic performance. By virtue of their inherent features, such as high torque density and multi-power port, the feasibility of MGd machines for applications, where continuously variable transmission (CVT) and power split are demanded, is also described.