A Review of Electro-Hydraulic Servovalve Research and Development

Abstract

This paper provides a review of the state of the art of electro-hydraulic servovalves, which are widely used valves in industrial applications and aerospace, being key components for closed loop electrohydraulic motion control systems. The paper discusses their operating principles and the analytical models used to study these valves. Commercially available units are also analysed in detail, reporting the performance levels achieved by current servovalves in addition to discussing their advantages and drawbacks. Adetailed analysis of research that investigates these valves via computational fluid dynamic analysis is also provided. Research studies on novel control systems and novel configurations based on the use of smart materials, wh

Digital Hydraulic Technology: Applications, Challenges, and Future Direction

“…Currently, hydraulic gap control is accomplished through the use of precise conventional servovalves. However, these valves encounter issues such as oil contamination, significant energy losses, and wear of the metering edge [6]. To overcome these challenges, digital hydraulics presents a promising solution.…”

“…While these valves offer excellent accuracy, precise control, and fast response times, their spool design leads to significant energy losses. This is because the pressurized fluid encounters high pressure drops as it flows through the narrow passages created by the spool during valve actuation [5], [6]. In [8], a medium-sized four-way three-position 4/3 spool valve was analyzed for power dissipation.…”

Fuels systems and components for future airliners fuelled with liquid hydrogen

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Characterization of rotary valve control vibration system for vibration stress relief applications

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