Low-cost high-performance ferrite permanent magnet machines in EV applications: A comprehensive review

Ferrite-based permanent magnet (PM) machines have been developed for many applications due to their highly desirable features such as low costs and stable supply chain. More recently, partly driven by the rapid uptake of the electric vehicle (EV) market, and partly due to the uncertainty of the supply chain of the rare-earth metals that are key components of the EV traction motor, there have been considerable interests in developing alternative solutions to rare-earth based PM motors. Due to their intrinsic low magnetic flux and prone to demagnetization, ferrite PM motors have not been previously considered for the more stringent EV applications. Hence, there is a growing body of research studies in addressing these challenges by deploying novel design strategies with varying proportions of ferrite materials, and with varying degrees of success. To date, there is a lack of comprehensive literature review of this class of evolving and yet highly promising electric machines that will offer a viable and sustainable alternative to EV traction applications. This paper aims to fill this gap and to provide a dedicated overview of these machines with a focus on their credentials as the 'traction motor of choice' in future EV markets. (C) 2020 Elsevier B.V. All rights reserved.