Optimal design of a switched reluctance motor with magnetically disconnected rotor modules using a design of experiments - Differential evolution (DoE-De) finite element analysis (FEA) based method

Switched reluctance (SR) machines are attractive because they present relatively high efficiencies and torque densities but have no permanent magnets. Their limitations include high torque ripple, mitigated in large inertia applications such as electric vehicles. This digest focuses on the multi-objective optimization of an external rotor switched reluctance motor. The stator has concentrated coils and the rotor is configured with magnetically isolated modules. The experimental methodology tries to identify the variables affecting the objectives of loss and active mass. After this, differential evolution is used for optimization. The digest illustrates the optimal design process associated with the development of a prototype machine and its systematic comparison with a conventional SR motor design. Improvements with respect to the chosen objectives over a reference machine are quantified through finite element analysis. Further, a method for comparing the different designs on the Pareto front and identify the best compromise designs is proposed.