A Study on the Prefilter to Protect Overshoot of Active Magnetic Bearing using Integral Type LQR-design Method

적분형 LQR 설계 기법을 이용한 능동자기베어링의 오버슈트 방지용 입력필터에 관한 연구

  • 강성구 (광주과학기술원 기전공학과 대학원) ;
  • 이기석 (충남대학교 기계공학과) ;
  • 정준모 (충남대학교 기계공학과) ;
  • 신우철 (한국기계연구원) ;
  • 홍준희 (충남대 기계공학과, 충남대학교 BK21 메카트로닉스 사업단)
  • Published : 2007.04.15

Abstract

Active magnetic bearing has been adopted to support the rotor by electomagnetic force without mechanical contact and lubrication process. A property of the control system for magnetic bearing is improved in accordance with making higher system gain. If the control system has integral part, an excessive overshoot response is shown by making higher integral gain. Therefore, this paper suggests a PID control system in order to eliminate the overshoot at the first stage and improve response characteristics to an impact disturbance at the status of levitation. The control gain was obtained by LQR design method which has the structure of I-PD control system in the state space. The PID control system containing prefilter has the same structure as the I-PD control system. Therefore, the PID control system adopted is able to be tuned by LQR design method. Finally, this paper shows the effect of the prefilter on the active magnetic bearing system through response experiments for levitation responses.

Keywords

References

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