The KSFM Journal of Fluid Machinery (한국유체기계학회 논문집)

Korean Society for Fluid machinery (한국유체기계학회)
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Study on the Electromagnetic Excitation System for the Measurement of Dynamic Coefficients of Air Foil Bearing for High Speed Rotor

초고속 회전체용 공기 포일 베어링의 동특성 계수 측정을 위한 전자석 가진장치에 관한 연구

  • Park, Cheol-Hoon (Advanced Manufacturing Systems Research Division, Korea Institute of Machinery & Materials) ;
  • Choi, Sang-Kyu (Advanced Manufacturing Systems Research Division, Korea Institute of Machinery & Materials) ;
  • Ham, Sang-Yong (Advanced Manufacturing Systems Research Division, Korea Institute of Machinery & Materials)
  • 박철훈 (한국기계연구원 첨단생산장비연구본부) ;
  • 최상규 (한국기계연구원 첨단생산장비연구본부) ;
  • 함상용 (한국기계연구원 첨단생산장비연구본부)
  • Received : 2013.01.15
  • Accepted : 2013.05.09
  • Published : 2013.06.01
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Abstract

Recently the requirement of long-term mobile energy source for mobile robot or small-sized unmanned vehicle is highly increased, and the micro turbine generator(MTG) which is known to have high energy and power density is under development. MTG is designed to have air foil bearing and high speed rotor of which operating speed is 400,000rpm. In the development stage of high speed rotor and bearing, stability analysis for the full operational speed range is essential and the dynamic coefficients such as stiffness and damping coefficients of bearing depending on the rotational speed are required for that. Although perturbation method is usually used to identify the dynamic coefficients, it's not easy to give the perturbation to the high speed rotating rotor. In this study, we present the dynamic coefficients measurement system for air foil bearing which consists of electromagnets, gap sensors, high speed motor and controller. This measurement system can exert the sine sweep force to the rotor-bearing, measure the displacement of rotor and get FRF(Frequency response function) of rotor-bearing. The least square estimation method is applied to identify the dynamic coefficients of bearing from the measured frequency response at the different rpm and the identified dynamic coefficients for the wide rotational speed range are presented.

Keywords

References

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