Effect of Axial-Layered Permanent-Magnet on Operating Temperature in Outer Rotor Machine

  • Luu, Phuong Thi (Dept. of Energy and Power Conversion Engineering, Korea University of Science and Technology) ;
  • Lee, Ji-Young (Electric Motor Research Center, Korea Electrotechnology Research Institute) ;
  • Kim, Ji-Won (Dept. of Energy and Power Conversion Engineering, Korea University of Science and Technology) ;
  • Chun, Yon-Do (Dept. of Energy and Power Conversion Engineering, Korea University of Science and Technology) ;
  • Oh, Hong-Seok (Star Group Industry Company (SGI))
  • Received : 2017.10.30
  • Accepted : 2018.07.06
  • Published : 2018.11.01


This paper discusses the thermal effect of the number of permanent-magnet (PM) layers in an outer rotor machine. Depending on the number of axial-layer of PM, the operating temperature is compared analytically and experimentally. The electromagnetic analysis is performed using 3-dimensional time varying finite element method to get the heat sources depending on axial-layered PM models. Then thermal analysis is conducted using the lumped-parameter-thermal-network method for each case. Two outer rotor machines, which have the different number of axial-layer of PM, are manufactured and tested to validate the analysis results.


Supported by : National Research Council of Science & Technology (NST)


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