Design of direct-driven permanent magnet synchronous motors for an electric sports car

A design process of a direct driven permanent magnet synchronous machine (PMSM) for a full electric sports car is presented. The rotor structure of the machine consists of two permanent magnet layers embedded inside the rotor laminations thus resulting in some inverse saliency. An integer slot stator winding was selected to clearly take advantage of the additional reluctance torque. The performance characteristics of the designed PMSM were calculated utilizing two-dimensional finite element method. Cross-saturation between d- and q-axes was taken into account in the calculation of synchronous inductances. The calculation results are validated with the measurements.