Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Flow Rate Control System Design for the Industrial Valve

산업용 밸브의 유량제어 시스템 설계

  • Choi, Jeongju (Department of Mechanical Engineering, Dong-a University)
  • 최정주 (동아대학교 기계공학과)
  • Received : 2019.08.21
  • Accepted : 2020.01.03
  • Published : 2020.01.31
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Abstract

This paper proposes a flow-rate control system for industrial valves. Industrial valves are used in piping systems to control the flow rate and pressure. In general, valves used in pipelines are classified into globe valves, butterfly valves, and ball valves according to the shape. Motor, hydraulic, and pneumatic systems are used for operating valves. The flow meter should measure the flow rate when configuring the flow-rate control system. On the other hand, because the flow rate of the valve can be expressed by flow coefficient, a control scheme is proposed using the pressure deviation, which measures at the front and rear of the valve. The transfer function for the valve, according to the control input, was estimated using the signal compression method. Based on the induced transfer function, the disturbance observer was designed to improve the command following the performance of the valve stem. The performance of the proposed control method is compared with the flow-rate control result using the flow meter used.

본 논문은 산업용 밸브의 유량제어시스템을 제안하였다. 산업용 밸브는 주로 배관시스템에 장착되어 유량 및 압력 제어에 사용된다. 제어밸브의 구조 및 작동 방식은 설치환경과 작업용도에 따라 상이하다. 밸브는 그 형태에 따라 그루브 밸브, 버터플라이 밸브 및 볼 밸브 등으로 분류되고, 구동방식은 모터를 이용하거나, 유압 및 공압을 이용하는 것이 일반적이다. 제어밸브를 이용한 유량제어시스템은 유량을 계측하여 피드백시스템을 구현하여야 하지만, 본 논문에서는 고가의 유량센서를 사용하지 않고 밸브의 개폐에 따른 유량변화를 실험하여 밸브 전후단의 압력차와 개폐정도를 이용하는 방법을 제안하였다. 밸브의 유량은 유량계수를 이용하여 밸브 전후단의 압력차와 밸브의 개폐정도로 표현할 수 있으므로 이를 이용하여 유량제어시스템을 설계하였다. 제어입력에 따른 밸브의 개폐를 나타내는 전달함수는 신호압축법을 이용하여 구하였으며, 이를 이용하여 밸브 스템의 명령추종성능을 향상시킬 수 있는 외란관측기를 설계하였다. 제안된 제어시스템의 성능을 검증하기 위해 제어밸브 전후단에 압력센서를 장착하여 제안된 제어방법의 성능이 유량센서를 이용한 경우에 준함을 확인하였다.

Keywords

References

  1. A. M. Jazi and H. Rahimzadeh, "Waveform Analysis of Cavitation in Globe valve," Ultrasonics, Vol. 49, pp. 577-582, 2009. DOI: http://www.doi.org/10.1016/j.ultras.2009.02.004
  2. B. Liu, J. Zhao and J. Qian, "Numerical analysis of cavitation erosion and particle erosion in butterfly valve," Engineering Failure Analysis Vol. 80, pp. 312-324, 2017. DOI: http://www.doi.org/10.1016/j.engfailanal.2017.06.045
  3. J. Jung and P. Seong, "Error analysis in improved motor control center method for stem thrust estimation of motor-operated valves in nuclear power plants," IEEE Transactions on Nuclear Science, vol. 50, No. 3, pp. 735-740, 2003. DOI: http://www.doi.org/10.1109/TNS.2003.812458
  4. S. Kang, S. Park, D. Lee, Y. Kim and D. Kim, "A study on the stem friction coefficient behavior of motor-operated valves," Nuclear Engineering and Design, Vol. 241, pp. 961-967, 2011. DOI: http://www.doi.org/10.1016/j.nucengdes.2011.01.017
  5. J. U. Byeon, C. H. Kim, S. H. Park, M. W. Lee and M. C. Kang, "Effects of Flow Rate and Discharge Pressure with Compressing Spring in Non-diaphragm Type Stem of Water Pressure Reducing Valve," Journal of the Korean Society of Manufacturing Process Engineers, Vol. 18, No. 5, pp.103-109, 2019. DOI: http://www.doi.org/10.14775/ksmpe.2019.18.5.103
  6. J. S. Lee, "Design and Computational Fluid Dynamics of Pressure Reducing Valve," Journal of Korea Society Academia-Industrial Cooperation, Vol. 13. No. 7. pp. 2853-2857, 2012. DOI: http://www.doi.org/10.5762/KAIS.2012.13.7.2853
  7. C. W. Kang, C. S. Yi, S. M. Jang and C. W. Lee, "A Study of the Measurement of the Flow Coefficient Cv of a Ball Valve for Instrumentation," Journal of the Korean Society of Manufacturing Process Engineers Vol. 18, No. 3, pp. 103-108, 2019. DOI: http://www.doi.org/10.14775/ksmpe.2019.18.3.103
  8. C. Alimonti, "Experimental characterization of globe and gate valves in vertical gas-liquid flows," Experimental Thermal and Fluid Science, Vol. 54, pp. 259-266, 2014. DOI: http://www.doi.org/10.1016/j.expthermflusci.2014.01.001
  9. L. Wanga, X. Liub and C. Wang, "Improved disturbance observer based control for airborne photoelectric stabilized platform," International Journal for Light and Electron Optics, Vol. 188, pp. 133-136, 2019. DOI: http://www.doi.org/10.1016/j.ijleo.2019.05.041
  10. 'N. Aoshima, "Measurement of nonlinear vibration by signal compression method," Journal of the Acoustical Society of America, vol. 76, no. 3, pp. 794-801, 1984. DOI: http://www.doi.org/10.1121/1.391303