Simulation and Experimental Validation of Flow-Current Characteristic of a Sample Hydraulic Servo Valve


1 Department of Mechanical Engineering,Sharif University of Technology

2 Department of Mechanical Engineering,Bu-Ali Sina University


This paper presents a novel model to simulate the
ow-current characteristic curve of
an electro-hydraulic servo valve in steady state condition. This characteristic curve has three major
zones: dead zone, linear zone and saturation zone. By using the presented approach, we can simulate
the behavior of all types of valves including under lapped, critical center (zero lapped) and over lapped
valves. A hydraulic tester has been designed and constructed for validation of the results. It can test
the performance of
ow-current and some other properties of the valve. Comparison of experimental and
simulated curves describes that the model has an acceptable accuracy in determining the four important
valve characteristics:
ow gain, saturation
ow, saturation current and dead zone. As a result, the
model can be used for other studies such as geometrical sensitivity analysis (the ultimate objective of this
modeling) or design optimization. Since this model is presented in a computer based algorithm, it can
be easily used to observe and measure the e ects of change in the parameters of interest (particularly
geometrical parameters of the valve) on the
ow-current curve.