Active Heave Compensation


What is Active Heave Compensation (AHC)?

In all Active Heave Compensation systems a Motion Reference Unit (MRU) measures actual vessel motions in all degrees of freedom, while a load sensing device determines actual wire tension. Based on this data, the control software calculates the necessary counter winding and unwinding of the winch and controls it in real time. By compensating more than 90 per cent of a ship’s movements, it’s possible to realise unparalleled precision and safe operations at any depth.

What is the difference between AHC and PHC?

Active Heave Compensation and Passive Heave Compensation

First, Active Heave Compensators are not making use of a spring concept where Passive Heave Compensators do. Second, one of the major differences between Active Heave Compensation and Passive Heave Compensation lies in power consumption. AHC requires an external power source while PHC does not. A control system actively attempts to accurately compensate wave movement by using power.

When to use Active Heave Compensation?

Typical areas of application are (active) heave compensated cranes, launch and recovery systems, on/off loading systems, helicopter platforms and many other solutions in need of stable operations.