Layered Structure of Permanent Magnet for Eddy Current Loss Reduction in Electric Machine Design

Inhomogeneous distribution of eddy current losses on the permanent magnets (PMs) in electric machines can lead to excessive loss and local demagnetization, threatening the motor system. Inspired by the theory of transformation quasi-static electromagnetic and technology of metamaterial, this paper applies a type of multi-layered structure to the PMs' design. The anisotropy and flexibility demonstrated by the proposed structure allow for intentionally manipulating the magnetic field, minimizing eddy current loss and maintaining output performance, thus surpassing the limitations of conventional loss reduction techniques.