Assessment of 12-slot, 14-pole permanent magnet flux switching machine with hybrid excitation for electric vehicle application

Permanent Magnet Flux Switching Machines (PMFSM) with hybrid excitation having 12-slot, 14-pole topology is assessed for its suitability for a 10kW (peak) traction drive for a micro size electric vehicle with a distributed power train. The design is optimized using 2D finite element analysis (FEA) and the performance is evaluated against the rated and the peak torque operations and over the New European Driving Cycle (NEDC) using “energy center of gravity” principle. The key limitations of this machine topology for EV applications are highlighted by comparing it with 12-slot, 14-pole surface mounted permanent magnet (SPM) machine with concentric windings designed against the same thermal and volumetric constraints.