Three-dimensional optimization of additively manufactured synchronous reluctance motors through leakage path design

Abstract Additively manufactured synchronous reluctance motors (SynRM) offer new design freedoms in the axial direction compared to conventional laminated rotors. However, many previous studies have focused on two-dimensional designs, not fully exploiting the potential of additive manufacturing. This paper presents a methodology for the three-dimensional design of additively manufactured SynRM rotors, with particular emphasis on leakage path reduction taking into account the mechanical robustness. The work begins with a two-dimensional basic design, which is refined through FEM-based parametric variations. This baseline is then extended to three dimensions, incorporating axial modifications of leakage paths that are enabled by additive manufacturing. Key design parameters including flux barrier heights, edge bridges, and middle ribs are systematically optimized considering both electromagnetic performance and mechanical constraints under centrifugal loading. Surface slotting strategies are explored to further reduce leakage flux and eddy current losses while maintaining mechanical stability through strategically placed bridges. The results demonstrate that a three-dimensional design approach achieves torque improvements compared to a conventional two-dimensional design while meeting mechanical stress limitations. The proposed design guidelines help making optimized use of additive manufacturing for SynRM rotors.