Comparative Study of Performance of Switching Control and Synchronous Notch Filter Control for Active Magnetic Bearings

능동 자기 베어링을 위한 동기 노치필터 제어기와 스위칭 제어기의 성능 비교 연구

  • Yoo, Seong Yeol (Institute of Advanced Transportation and Vehicle Research, Chungnam Nat'l Univ.) ;
  • Noh, Myounggyu (Dept. of Mechatronics Engineering, Chungnam Nat'l Univ.)
  • 유승열 (한국해양과학기술원 해양시스템연구부) ;
  • 노명규 (충남대학교 메카트로닉스공학과)
  • Received : 2012.09.13
  • Accepted : 2012.12.03
  • Published : 2013.04.01


Switching controllers for active magnetic bearings are claimed to minimize the copper losses because they do not use bias currents. In this study, we compare the performances of the switching controller with those of the widely used proportional-derivative (PD) controller. The PD controller is combined with a synchronous notch filter to reduce the effect of the unbalance disturbance. For a fair and objective comparison, the PD controller is designed systematically. The switching controller is designed so that the dynamics of the two controllers are almost identical. A system model is developed. This model includes the flexible modes of the rotor and the dynamics of the sensors and amplifiers. The simulation results show that the switching controller indeed reduces the copper loss at lower speeds. However, it fails to operate around the speed close to the bending mode of the rotor.


Active Magnetic Bearing;Power Minimization Control;Switching Control;Synchronous Notch Filter


Supported by : 한국연구재단


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