Journal of Drive and Control (드라이브 ㆍ 컨트롤)

The Korean Society for Fluid Power and Construction Equipment (유공압건설기계학회)
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A Study on the Oil Inertia Effect and Frequency Response Characteristics of a Servo Valve-Metering Cylinder System

서보밸브-미터링 실린더 시스템의 오일 관성효과와 주파수 응답 특성에 관한 연구

  • Yun, Hongsik (Department of Mechanical System Engineering, Kumoh National Institute of Technology) ;
  • Kim, SungDong (Department of Mechanical System Engineering, Kumoh National Institute of Technology)
  • Received : 2021.03.31
  • Accepted : 2021.04.08
  • Published : 2021.06.01
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Abstract

The spool displacement signal of a directional control valve, including the servo valve, can be considered as the standard signal to measure dynamic characteristics. When the spool displacement signal is not available, the velocity signal of a metering cylinder piston can be used. In this study, the frequency response characteristics of the metering cylinder are investigated for the spool displacement input. The transfer functions of the servo valve-metering system are derived taking into consideration the oil inertia effect in the transmission lines. The theoretical results of the transfer functions are verified through computer simulations and experiments. The oil inertia effect in the transmission lines was found to have a very significant effect on the bandwidth frequency of the servo valve-metering cylinder system. In order to more precisely measure the dynamic characteristics of a servo valve, the metering cylinder should be set up to minimize the oil inertia effect by increasing the inner diameters of the transmission lines or shortening their lengths.

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Acknowledgement

이 연구는 금오공과대학교 학술연구비(과제번호 : 2020-0128-0001) 지원에 의하여 수행되었음을 밝힙니다.

References

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