Optimal design of synchronous reluctance machine: A feasible solution to eliminating rare earth permanent magnets for vehicle traction applications

Purpose ‐ The purpose of this paper is to present optimally designed synchronous reluctance machine (SynRM) to demonstrate the feasibility of eliminating the use of rare earth permanent magnet (PM) in electric machine for vehicle traction applications. Design/methodology/approach ‐ A typical rare earth interior permanent magnet (IPM) machine is used as the benchmark to conduct the optimal design study. Based on the flux distribution, major changes are made to the rotor lamination design. Enhanced torque production and lower torque ripple are specifically targeted as the two main objectives of the proposed design approach. Findings ‐ As a result, the optimally designed SynRM can achieve performance very close to that of the benchmark PM machine with a potential for further improvement. Originality/value ‐ Discussions of IPM replacement by optimally designed SynRM in electrical and hybrid electrical vehicles are given in terms of performance and cost.