Electrohydraulic Flow Matching: The next generation of load-sensing controls

Advanced hydraulic controls speed machine response, eliminate oscillations, and save energy. Wheel loaders with electrohydraulic flowmatching controls use less energy than machines with conventional loadsensing controls. A major challenge facing mobileequipment designers is dealing with a large number of actuators that require hydraulic flow. Machines frequently have up to 10 hydraulically powered functions, with three or more operating simultaneously. And often, due to space, weight, or cost reasons, a common pump supplies all the circuits. Thus, as an operator actuates various subsystems, control valves must handle the demanding task of compensating for flow changes and disturbances. The goal is to ensure adequate flow to all actuators, even when operating several systems simultaneously, so there is no drop off in machine performance. To ensure flow matches demand, hydraulics manufacturers fit control valves with pressure compensators that control flow rates or distribution. Two designs predominate. One, called load sensing (LS),