Cylinder Pressures in a Position Controlled System With Separate Meter-in and Meter-out

Gerhard Ruth
Department for Product Development, University of Leoben, Leoben, Austria

Emil Zæv
Faculty of Mechanical Engineering, Ss.Cyril and Methodius University in Skopje, Skopje, Macedonia

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp1392a25

Ingår i: 13th Scandinavian International Conference on Fluid Power; June 3-5; 2013; Linköping; Sweden

Linköping Electronic Conference Proceedings 92:25, s. 251-259

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Publicerad: 2013-09-09

ISBN: 978-91-7519-572-8

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


Hydraulic servo system driven with separate meter-in and meter-out valves provide more flexibility with respect to energy efficiency and dynamic properties. In the current problem the operation of such a configuration involves to keep a desired position constant; while an external load force is applied. The position control cannot compensate for fast load fluctuations beyond a certain frequency limit. For this case it can be desired to adjust the static pressures in the cylinder chambers to defined values. The paper describes how to influence this pressures giving weights to the control signals for both moving directions for each valve. With the help of a simulation model the design results are verified. Higher pressure levels decrease the danger of cavitation and inhibit lowering the bulk modulus of the oil volume. The asymmetric control of the valves even lead to better energy efficiency during position control.


Servo control; smismo; energy efficieny


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