Energy-saving control of hydraulic systems with novel programmable valves

The paper studies the energy-saving adaptive robust motion control of a single-rod hydraulic cylinder through the use of programmable valves-a unique combination of five proportional cartridge valves. The programmable valves decouple the meter-in and meter-out flows and provide true cross port regeneration flow which in turn allows tremendous control flexibility. Although at the expense of controller complexity, if well utilized, the added control flexibility can be used to significantly reduce the fluid power energy usage in a number of motion and loading conditions to meet the society's need for energy conservation while without sacrificing the achievable motion control accuracy.