Design of Synchronous Reluctance Motor for Additive Manufacturing Technology

In this dissertation, the possibility of fabricating ferromagnetic cores for electrical machine applications through additive manufacturing techniques is investigated, in particular rotors for synchronous reluctance and permanent magnet assisted reluctance motors. The thesis consists of three main parts: optimization of the printing process, realization of the printed rotors to demonstrate the possibility of fabricating such components by using additive manufacturing and finally optimization of the rotor topology to achieve the best performance. The first part of the thesis discusses the Design of Experiment conducted to find the optimal set of process parameters to be able to fabricate ferromagnetic cores with excellent electromagnetic properties and without structural defects such as cracks and breaks. It also highlights how the choice of process parameters is essential for fabricating high-quality components and how they affect the properties of the printed material. The second part of the thesis analyzes several motor prototypes with printed rotor. Two types are investigated: a synchronous reluctance motor and a permanent magnet assisted one, both by finite element analysis and experimental tests, highlighting how the optimization of the printing parameters and the characterization of the ferromagnetic material allowed obtaining excellent agreement between simulation and experimental tests and high-quality components. Finally, the optimization of the rotor topology is presented. A new design approach is proposed. The flux barrier profile is described with Bézier curves. This technique allows any type of flux barrier profile to be obtained with a limited number of variables. In this way complex rotor geometries are investigated with the aim of being fabricated using additive manufacturing processes.