Overview of permanent-magnet fault-tolerant machines: Topology and design

Permanent-magnet (PM) machines have attracted a lot of interest in various applications since they have the merits of high torque density, high power density and high efficiency. However, issue of poor fault tolerance of the conventional PM machines restricts their practical applications in the field of safety-critical applications, e.g. aerospace, electric vehicle, electrical propulsion and wind power generator applications. An enormous amount of work has been done to improve the fault-tolerant capability of PM machines. This paper will review research work on PM fault-tolerant machines up-to-date, including modular design, short-circuit current limitation design, redundant design, ease of thermal dissipation of PM design, and torque enhancement design techniques. The work of this paper can provide some references for future studies and engineering applications of PM fault-tolerant machines for safety-critical applications.