Electromagnetic Performance Analysis of an Axial Flux Hybrid Excitation Motor for HEV Drives

Drive machines of hybrid electric vehicles (HEVs) employ axial flux permanent magnet (AFPM) motors on account of its high power density and high efficiency. The technique takes full advantage of the performance and manufacturing preponderances of soft magnetic composites (SMC). Specifically, it includes low iron consumption at high frequency and high speed, convenient machining and small relative magnetic permeability. An extra DC excitation winding is appended to the motor to conquer the drawbacks of the constant power speed ratio. It can provide an extremely wide constant power speed region, which ensures the excellent property of the machine. Finite element algorithm (FEA) is used to assess the property of axial flux hybrid excitation motor (AFHEM). Comprehensive analysis has fully indicated that larger torque density and wider speed range can be obtained by the AFHEM, which is appropriate for the application of HEV drives.