Additive Manufacturing of Next Generation Electrical Machine Windings: Opportunities in Fusion Engineering?

More electric propulsion across automotive and aerospace has led to a demand for significant improvement in the power density of electrical machines. This has, in turn, triggered research into advanced manufacturing methods for higher-performance magnet systems in machines. The application of laser powder bed fusion (LPBF), a form of additive manufacture (AM), to the current carrying coils of the electromagnetic circuit of a machine has allowed several significant improvements to the design of these parts. One benefit which can be realized in this way is the tailoring of conductor form to the operating field and the alteration of conductor topology to reduce the ac loss. Another advantage of these manufacturing techniques is the ability to introduce methods of direct cooling to the coil, including highly efficient heat exchangers derived from generative design techniques. It is significant that the electrical conductivity achieved is now equivalent to that of conventional drawn Cu wire. This article hypothesizes that the lessons learned in developing production methods for next-generation, high-performance components for electric machines might also find utility in the very demanding electromagnetic circuits found in magnetic confinement fusion. Potential benefits for the production of cable-in-conduit conductor (CICC) superconducting (SC) bus-bar joints, or even larger elements of conductors are discussed. This is used to motivate future experimental studies of the mechanical and electrical performance of AM Cu at cryogenic temperatures as well as the further development of the manufacturing state of the art.