Speed Control Of The Magnet Gear-Based Speed Reducer For Non-contact Power Transmission

비접촉 동력 전달을 위한 마그네트 기어 기반 감속기의 속도 제어에 관한 연구

  • Jung, Kwang Suk (Department of Mechanical Engineering, Korea National University of Transportation)
  • 정광석 (한국교통대학교 기계공학과)
  • Received : 2016.04.27
  • Accepted : 2016.07.07
  • Published : 2016.07.31


Using the magnet gear, it is possible to transmit power without mechanical contact. As the drive shaft in a magnet gear-based speed reducer system is isolated from the drive shaft, the system is a two-inertia resonance system that should cope with an external load with the limited air-gap stiffness. On the other hand, the drive shaft or low-speed side is controlled only by the torque of the drive shaft through an air-gap, and the excessive oscillation or the slip can then be generated because of an abrupt disturbance that is different from the general mechanical gear system. Therefore, the disturbance loaded at the low speed side should be measured or estimated, and considered in the control of the driving shaft. This paper proposes a novel full-state feedback controller with a reduced-order observer for the speed reducer system using a magnet gear with a unified harmonic modulator. The control method was verified by simulation and experiment. To estimate the load at the low speed side, a novel observer was designed, in which the new state variable is introduced and the new state equation is formulated. Using a full-state feedback controller including the observer, the test result against disturbance was compared with two D.O.F PI speed controllers. The pole slip was compensated within relatively a short time, and the simulation result about the estimated variable shows a similar tendency to the test result. The test results showed that the magnet gear-based reducer can be applied to an accurate servo system.


Supported by : 한국연구재단


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