Axial magnetic gear with a closed magnetic path

자기 폐회로를 갖는 축형 마그네틱 기어

  • Jung, Kwang Suk (Department of Mechanical Engineering, Korea National University of Transportation)
  • 정광석 (한국교통대학교 기계공학과)
  • Received : 2017.05.01
  • Accepted : 2017.07.07
  • Published : 2017.07.31


A magnetic shutter gear is a device that transfers mechanical power by synchronizing the magnetic field between permanent magnet layers facing circumferentially through a harmonic modulator. However, magnetic gears uses many rare-earth permanent magnets to guarantee comparable torque density to that of mechanical reducer. Hence, we propose a novel axial magnetic gear with a dramatically reduced number of permanent magnets and a closed magnetic path. The torque of the system was compared to that of an existing shutter gear through a harmonic analysis of the air-gap magnetic field. The modulator thickness and open ratio were considered as the primary design parameters, and the cogging effect was analyzed for variation of the reduction ratio. A dynamic model between the high-speed side and low-speed side was derived, and position control was performed for a constructed hardware implementation.


Axial magnetic gear;Cogging effect;Finite element analysis;Harmonic modulator;Linear control;Magnetic path;Parametric analysis


Supported by : 한국연구재단


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