Active heave compensation control system for winches

Scantrol AS provides electronic control systems for offshore, fishing, and marine research applications. The company’s new active heave compensation system, Scantrol AHC, is a control system for winches and cranes used for subsea operations. It is designed to give precise control of load position when a vessel is in motion. The AHC can be adapted to all different hydraulic and electric winches.

BASIC SYSTEM

The basic system includes an iCON ACH controller, motion reference unit, operator’s panel, and radio control.

The iCON AHC controller is a high-end, real-time controller (RTC) with hardware and software dedicated for high speed AHC control, and interface to both electric and hydraulic winches.

The motion reference unit (MRU) measures the vessel’s heave, pitch, and roll motion so that the system can pay in and pay out to compensate for the movement of the vessel and keep the load at a constant distance to the sea bed.

The Operator’s Panel features joysticks and touch screen. Layout and functionality can be adapted to operational requirements.

Radio Control is tailored for safe and reliable winch operation.

PREDICT AHC PERFORMANCE

Scantrol Active Heave Compensation is suitable for many existing winches as they often have the speed and torque characteristics suitable for AHC. In many cases, the AHC can be fitted to existing winches with little or no modification to the winch.

Scantrol has designed an AHC toolbox that makes it possible to determine AHC performance with an existing winch. The Scantrol AHC Analyzer can predict AHC performance with different loads and varying vessel motion.  In many winch applications, only a fraction of the winch design load is used during normal operation, and the spare torque can be used for AHC.

Screen shot from the Scantrol AHC Operator’s monitor shows the vessel motion (upper graph) and the corresponding load motion with and without AHC (lower graph).

AHC FOR ALL WINCHES

The AHC system can be used to ensure precise and safe landing and pickup of equipment on the seabed without influence from the ship’s motion. Docking of ROVs can be done safely, without vessel movement compromising the TMS position.

The system makes it possible to work even in harsh sea conditions. The operation time will increase as less downtime will be spent waiting for good weather conditions.

Scantrol is an independent supplier of winch control systems for marine and offshore applications, located in Bergen, Norway. Scantrol control systems range from simple winch controls to the most advanced controls for AHT, seismic survey, marine research, and fishing vessels, as well as semisubmersibles and barges.