Traction PMASR Motor Optimization According to a Given Driving Cycle

Electric motors are ideal candidates for traction applications due to their optimal electromechanical characteristic, high efficiency, and manufacturing simplicity. Nowadays, the most attractive solutions are represented by the synchronous machines, due to the great advantages in terms of high performance and mass saving. Motor optimization is often performed in one or few operating points, usually located along the continuous or overload torque profile. On the other hand, the actual motor operation depends on the driving cycle of the vehicle, which might be different than the rated conditions. This paper deals with the design and optimization of a permanent-magnet-assisted synchronous reluctance motor according to two different duty cycles, one for city driving and another for mixed driving operation. A procedure is proposed to evaluate the most effective design areas by means of a series of representative points, which have been considered for the global optimization. The results and the advantages of the adopted methodology against the conventional procedure and optimized solutions are highlighted and discussed.