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Primary Active Heave Compensator


Primary rotary Active Heave systems (PAHC) are integrated completely into the winch and require minimal space on deck. No additional operator is needed to achieve high accuracy and reliability.

Primary AHC systems from Rexroth are based on proven hydraulic pumps and motors that are manufactured in large numbers. The Motion Reference Unit sends its data to the main controller, which calculates the set point and, in real time, controls the hydraulic variable pump that is connected to a fixed motor. This involves adjusting the winch speed and direction by varying the swivel angle of the pump, thus regulating the volume flow rate. To change the winch’s rotation direction the hydraulic pump swivels over its centre and works as a motor. Hence, the primary active heave compensator is a closed loop hydraulic system.


Energy recovery

State of the art primary Active Heave Compensation systems are designed to recover energy in different phases of compensation by feeding it back to the electric grid, or store the energy in capacitors or fly wheels. The system adapts to varying load and operating conditions to maintain safe and efficient compensation, without overloading the winches.

Installation on existing equipment

One special advantage: Primary rotary Active Heave Compensators can also be integrated into already installed winches and cranes, enlarging the window of operation with minimal effort and cost.