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 Frequency Response Signals of a Servo Valve

서보밸브의 주파수 응답 신호에 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 : 2021.02.01
  • Accepted : 2021.02.11
  • Published : 2021.03.01
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Abstract

The flow signal or spool position signal is used to determine the dynamic characteristics of directional control valves. Alternatively, the signal of spool position or flow can be replaced with the velocity of a low friction, low inertia actuator. In this study, the frequency response of the servo valve equipped with a spool position transducer is measured with a metering cylinder. The input signal, spool displacement, load pressure, and velocity of the metering cylinder are measured, and the theoretical results from the transfer function analysis are verified. The superposition rule for magnitude ratio and phase angle was found to be always applicable among any signal type, and it was found that the load pressure signal is not appropriate for use as the signal for measuring the frequency response of a servo valve. It was confirmed that the frequency response of a servo valve using metering cylinder was similar to the results from a spool displacement signal. The metering cylinder used for measuring the frequency response of a servo valve should be designed to have sufficiently greater bandwidth frequency than the bandwidth frequency of the servo valve.

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References

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