Electrohydraulic servosystems are commonly used in various engineering applications due to their high power-to-weight ratio, good performance, and ease of control. Electrohydraulic servovalves are affected by centrifugal forces when they are used in the fields of spaceflight, earthquake simulation, and geotechnique. Based on theories of fluid dynamics and performance of an electrohydraulic servovalve, the fluid flow and structure of a two-stage electrohydraulic servovalve are analyzed when the valve is affected by centrifugal forces in operation. From calculation and experimental data it is found that centrifugal acceleration is directly proportional to null shift and the scale factor is formulated. Relevant methods to reduce the influence of the centrifugal force are provided.

Issue Section:
Technical Papers
Keywords:
electrohydraulic control equipment, servomechanisms, performance evaluation, valves, nozzles
Topics:
Centrifugal force, Nozzles, Valves, Torque
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 by ASME
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