System arranged on a marine vessel or platform, such as for providing heave compensation and hoisting

摘要

A system on a marine vessel or platform supports a load while allowing heave compensation. The load is supported via a hydraulic actuator. A transformer of the system includes a power source and at least one hydraulic pump/motor, for communicating energy between any two of: the hydraulic actuator; a hydraulic accumulator; and a power source. A valve associated with the pump/motor is switchable during at least one cycle of the pump/motor for selectively providing fluid communication between a drive chamber of the pump/motor and any of the hydraulic actuator, the hydraulic accumulator, and a hydraulic fluid reservoir, via at least one port of the drive chamber, so as to allow a desired displacement of hydraulic fluid from the pump/motor to be obtained.