Electrohydraulic servovalves are used in a variety of industrial, military, and aerospace applications. For some of these applications the servovalve must meet stringent dynamic performance criteria while under the influence of external disturbances. The most common of these external disturbances is vibration. Vibration can not only have an affect on valve performance, but can also affect valve stability. This thesis deals with the development of a dynamic model of the amplifier lines and line orifice of a two stage servovalve. The amplifier lines are thought to affect the stability of two stage servovalves under vibration. The amplifier lines are the hydraulic 'communicator' between the first and second stages of the valve. The developed model is simulated using Simulink and MATLAB for a servovalve with a history of vibration induced stability problems. For this valve, there are certain amplifier line and orifice configurations that cause the valve to exhibit increased stability under vibration. The results of the model simulations for known stable and unstable configurations are discussed. Recommendations for usage are also presented.
Library of Congress Subject Headings
Hydraulic control; Valves--Vibration; Hydraulics
Department, Program, or Center
Mechanical Engineering (KGCOE)
Cook, David, "Development of a dynamic model for a two stage servovalve amplifier line and orifice" (1997). Thesis. Rochester Institute of Technology. Accessed from
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