VLT® High Power Drives Maintain Position in High Sea
MV SIA is the newest cable-laying vessel from CT Offshore, located in Odense, Denmark. CT Offshore specialises in installing and maintaining offshore cables for the many new wind turbine farms that will deliver environmentally friendly energy in the years to come.
VLT® High Power frequency converters strengthen the ship’s tunnel thrusters, while active harmonic filters provide high voltage quality for the vessel’s 3.2 MW generator. CT Offshore has converted an outdated ferry from 1978 into a cutting-edge cable-laying vessel with all the latest equipment for installing and maintaining cables between off shore wind turbines and the electricity network on shore.
The entire ship has undergone a full refurbishment in which all the installations have been renovated, and a good deal of special equipment has been installed to handle the cable work. There are a total of 47 cabins where the ship’s crew and the client’s wind turbine experts can live and work under comfortable conditions.
To hold the SIA in position with a precision of 200 mm the Dutch Thruster Group supplied 7 GME e-motor driven 200kW tunnel thrusters in the bow (4) and stern (3). Together with an existing thruster of 400kW the combined power of 1.8 MW in full integration with a Navis dynamic positioning system navigates the vessel along the preprogrammed route – even under the difficult weather conditions and strong currents that often plague the North Sea. To provide power to the thrusters and other equipment, the Dutch Thruster Group also supplied a power plant of 3.2 MW, consisting of four Mitsubishi diesel generators and two 190A VLT Advanced Active Filters.