Scaling process of synchronous reluctance machines for automotive applications

Synchronous reluctance machines (SynRM) are increasingly considered as viable alternatives to conventional electrical machines in different applications. Regarding traction drives, this machine type should be studied further with respect to the basic requirements, namely efficiency, low cost and high power density. This paper investigates a scaling process for synchronous reluctance drives that are suitable for mid-range electrical vehicle traction applications. A multiphysics FEA-simulation using Opera 2D was performed to find the optimal trade-off between electromagnetic and mechanical characteristics. A radial-laminated rotor design with multiple flux-barriers was preliminary optimized for a high torque per axial length. Based on these results, a coupled analysis of torque production and rotor stability led to a number of different rotor designs used for pareto-optimization. Applying this method, the scaling of SynRM was analyzed with respect to the power density.