A METHOD OF CONTROLLING A HYDRAULIC ACTUATOR, A HYDRAULIC ACTUATOR, A HYDRAULIC SYSTEM AND A WORKING MACHINE

摘要

A method of controlling a hydraulic actuator (40, 42), wherein the hydraulic actuator (40, 42) comprises a linear double-acting output member (46), and at least three working chambers (84) in fluid connection with the output member (46), the working chambers (84) having respective effective areas with a non-binary relationship; wherein the method comprises selectively fluidly connecting (S1) each working chamber (84) to either a high- pressure side (48) or a low-pressure side (50) to provide a plurality of discrete pressurization states (92) of the hydraulic actuator (40, 42); determining (S2) at least one of the pressurization states (92) as a prevented pressurization state; and transitioning (S3) between a plurality of allowed pressurization states among the pressurization states (92) while preventing transition to the at least one prevented pressurization state. A hydraulic actuator (40, 42) and a hydraulic system (20) are also provided.