Hydraulic system with open loop electrohydraulic pressure compensation

摘要

A hydraulic system has a pump that furnishes pressurized fluid to a supply node connected to a plurality of functions. Each function includes hydraulic actuator and a control valve assembly through which fluid flows both from the supply node to the hydraulic actuator and from the hydraulic actuator to a return line. A control method involves receiving a plurality of commands, each designating desired operation of a function. Each command is separately used to derive a flow value designating an amount of flow for the respective function, a load value indicating a load magnitude related to the respective function, and a pressure value denoting a supply pressure for the respective function. Then, the control valve assembly for each given hydraulic function is operated in response to the flow and load values for that function and in response to the pressure value that is greatest among the plurality of functions.

主权项

1. A method for operating a hydraulic system having a pump, a return line, a supply node that receives pressurized fluid from the pump, and a plurality of hydraulic functions, each hydraulic function including a hydraulic actuator and a control valve assembly through which fluid flows from the supply node to the hydraulic actuator, said method comprising:
receiving a plurality of commands, each designating desired operation of a different one of the plurality of hydraulic functions; for each command, employing that command to derive a function load value designating a load magnitude related to the respective hydraulic function and a function pressure value indicating a level of supply fluid pressure for the respective hydraulic function; and for each given hydraulic function for which a command was received, operating the associated control valve assembly for the given hydraulic function in response to the function load value for that given hydraulic function and in response to the function pressure value that is greatest among the plurality of hydraulic functions.