The Resonance Converter - A Novel Method for Hydraulic Fluid Power Control

The application of switching control to hydraulic drives in an energy-efficient and a smooth operation providing manner needs some intermediate oscillation system between the switching valve and the drive. Om case of the resonance converter this is realised by a hydraulic piston, attached with a spring and some inertia, and a switching valve which connects the cylinder alternately with the pressure-, tank- and output-line. Without any friction, this system generates a flow-rate independent from the pressure required at the drive. The role of the free system parameters for flow rate and efficiency is discussed by mathematical models. Experiments are reported which show that the mathematical results are essentially correct and that such a system actually works.