자기부상시스템의 외란관측기 제어기에 Q 필터가 미치는 영향에 관한 연구

A Study on the Influence of Q-filter on Disturbance Observer Controller for Electro-Magnetic Suspension Systems

  • 투고 : 2015.09.02
  • 심사 : 2015.09.15
  • 발행 : 2015.10.30


The disturbance observer (DOB) controller has been widely used in various industrial applications since it is capable of achieving robust stability and disturbance rejection. In this paper, we study the effect of Q-filter on disturbance observer controller for Electro-Magnetic suspension (EMS) systems. We consider three Q-filters and analyze their effects on the robust stability against parameter uncertainties due to mass variation. Moreover, we investigate the influence of sensor noise for three Q-filters. According to our study, robust stability improves as the order of Q-filter decreases. On the other hand, the larger the order of Q-filter, the more the effect of sensor noise can be removed.


Electro-Magnetic suspension system;Disturbance Observer;Model uncertainties;Disburbance Rejection


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연구 과제 주관 기관 : 한국에너지기술평가원(KETEP)