Transverse- and Axial-Flux Permanent Magnet Machine With C-Type SMC Stator: A Solution for Ultra-Flat Applications

This article proposes a novel transverse- and axial-flux permanent magnet machine (T-AFPM) using a C-type stator core for reducing system size via an ultra-flat shape. With an axial length of only 19.7 mm, this ultra-flat shape contributes markedly to reducing system size in industrial applications such as water pumps. In general, AFPMs are suitable for a flat shape because of their high torque density with a short axial length. However, it is difficult to use conventional AFPMs to achieve an ultra-flat shape because of structural problems and insufficient performance. By contrast, the proposed T-AFPM achieves a highly manufacturable structure, high efficiency, and the required output power despite its extremely short axial length. Herein, the T-AFPM is compared with conventional AFPMs with various configurations by means of three-dimensional finite-element analysis, and experiments on a T-AFPM prototype are reported. From the simulation and experimental results, the proposed T-AFPM shows high efficiency (IE5 class), the required output power, and suitable structural properties for an ultra-flat shape.