METHOD FOR CREATING MODEL-BASED LOOKUP TABLE FOR CONTROL FLOW RATE ESTIMATION OF HYDRAULIC DEVICE, MODEL-BASED LOOKUP TABLE FOR CONTROL FLOW RATE ESTIMATION, AND PRESSURE ESTIMATION METHOD

摘要

To propose a model-based lookup table for control flow rate estimation of a hydraulic device that can accurately estimate a control flow rate from a hydraulic control valve to a hydraulic cylinder in a hydraulic device, and can be easily mounted to an actual machine.SOLUTION: A model-based lookup table for control flow rate estimation is used in a hydraulic device 1 to estimate a cap side flow rate Qof hydraulic oil, which is an unsteady flow rate element that flows into a cap side hydraulic chamber of a hydraulic cylinder 2, from a spool displacement u of a hydraulic control valve 3 and a cap side pressure pof the hydraulic cylinder. A non-linear nominal model for defining the hydraulic device is set, and input and output measurement values not including the flow rate of the hydraulic device are processed offline, to obtain a cap side flow rate matrix for estimating the cap side flow rate from the non-linear nominal model. Next, the Hilbert projection theorem is applied to reduce the dimension of the obtained cap side flow rate matrix, to obtain a cap side optimum flow rate matrix used as a lookup table.SELECTED DRAWING: Figure 1