Proportional Position Control of Low-Pressure Water Hydraulic Cylinder

This paper presents briefly some main properties of two proportional valves that are possible to use in low-pressure water hydraulics. The other valve is a commercial water hydraulic proportional valve and other is a modified pneumatic on/off-valve. These valves are used in position control of low-pressure water hydraulic cylinder drive. Experimental results show that good position accuracy and small variation can be achieved with commercial water hydraulic proportional valve. The results with the modified pneumatic on/off valve are not quite as good but they are still promising and show that some further development should be done.