Design of Surface-Mounted Permanent Magnet Synchronous Motor Considering Axial Leakage Flux by using 2-Dimensional Finite Element Analysis

  • Lee, Byeong-Hwa (Electric Powertrain R&D Center, Korea Automotive Technology Institute) ;
  • Park, Hyung-Il (Advanced Brake Engineering Team, R&D Center, Hyundai Mobis) ;
  • Jung, Jae-Woo (Advanced Brake Engineering Team, R&D Center, Hyundai Mobis)
  • Received : 2017.11.21
  • Accepted : 2018.05.31
  • Published : 2018.11.01


This paper deals with optimum design of surface mounted permanent magnet synchronous motor (SPMSM) for automotive component. For a compact system structure, it was designed as a motor with a 14-pole 12-slot concentrated winding and hollow shaft. The motor is a thin type structure which stator outer diameter is relatively large compared to its axial length and is designed to have a high magnetic saturation for increasing the torque density. Since the high magnetic saturation in the stator core increases the axial leakage flux, a 3-dimensional (3-D) finite element analysis (FEA) is indispensable for torque analysis. However, optimum designs using 3-D FEA is inefficient in terms of time and cost. Therefore, equivalent 2-D FEA which is able to consider axial leakage flux is applied to the optimization to overcome the disadvantages of 3-D FEA. The structure for cost reduction is proposed and optimum design using equivalent 2-D FEA has been performed.


Supported by : Hyundai Mobis


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