"Plastic" electric motors: a viable solution for axial flux machines

After more than 100 years of development, rotating electric machines are a mature industrial product. Nevertheless improvements are still possible for specific applications, and it is likely that the major evolution will be promoted by unconventional structures. Among them, some of the most interesting proposals have a three dimensional flux path. Due to the magnetic circuit geometry, the unconventional "3D motors" suffer the difficulties in adopting the laminated iron technology: the problem can be afforded adopting new materials, such as plastic or powder magnetic composite material. Hence, unconventional motor structures and new materials open a possible evolution in the electric machines and drives scenario. Today, plastic materials are an infrequent choice for the electric machines structural parts, but, pioneering applications, such as aeronautical components, let some technological scouting: a low weight-high efficiency plastic axial flux motor for a solar flying platform is presented as example of a combined new material-new geometry development.