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On the Robustness of Disturbance Observer based Controller for DC Motor with Unstructured Uncertainty

비구조적 불확실성이 존재하는 DC모터에 대한 외란관측기 기반 제어기의 강인성에 대한 연구

  • Jo, Nam-Hoon (Dept. of Electrical Engineering, Soongsil University)
  • Received : 2016.08.29
  • Accepted : 2016.12.21
  • Published : 2017.01.01

Abstract

In this paper, we study the robustness of disturbance observer based controller for DC motor in the presence of unmodeled dynamics. It is well known that the robustness property usually becomes weaker as the control gain becomes larger. On the contrary to this expectation, it is shown that the phase margin of DOB controller remains quite a large value even though the time constant of Q-filter becomes smaller. The computer simulation results show that DOB controller is able to stabilize the motor system even in the presence of unmodeled dynamics. On the contrary, the unity-feedback system fails to maintain stability when a high gain feedback is employed for the purpose of achieving better disturbance attenuation performance.

Keywords

References

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