Design optimisation and performance evaluation of a rare-earth-free Permanent Magnet Assisted Synchronous Reluctance Machine for electric vehicle traction

The paper focuses on the design optimisation and performance evaluation of low remanence Permanent Magnet Assisted Synchronous Reluctance Machines (PMA SynRM) against driving cycles. It demonstrates the impact of different driving cycles, such as the NEDC and Artemis Urban, on the design and attainable energy efficiency of PMA SynRM considered for traction applications through the use of design case studies. The parameter optimisation trends against these characteristically different driving cycles are coherently analysed with respect to the energy loss distribution, magnet usage and reluctance torque capability of the PMA SynRM. The performance of the optimised PMA SynRM is then compared to that of a conventional Interior Permanent Magnet Synchronous Machine (IPMSM) employing sintered NdFeB magnet material and optimised against the same driving cycle.