Post by ferryfast admin on Aug 19, 2011 12:25:34 GMT -5
Wind farm service ship uses AC drives
www.motorship.com/news101/wind-farm-service-ship-uses-ac-drives
19 Aug 2011
Vacon of Finland has supplied its low harmonic air-cooled AC drives to control the propulsion system and operation of a deck crane on Danish wind turbine service vessel Wind.
Wind is a self-propelled heavy-lift vessel owned by. DBB Jack-Up Services, which is capable of replacing heavy components on wind turbines at a height of up to 100m.
The thrusters used for Wind’s propulsion and DP systems are dynamically controlled by Vacon AC drives. Vacon says that this brings energy savings, because thruster speed can be optimised for the actual speed of the vessel, giving maximum grip on the water. In conventional diesel engine installations speed is adjusted in steps, so that it is often too low or too high, resulting in a looser grip on the water. The torque of the thrusters is monitored closely by the Vacon AC drives to ensure that the thrusters are only operated within the permitted torque range. This is essential when changing the direction of the azimuth thruster unit, for example, since this cannot accept full torque if it is at an angle to the direction in which the vessel is sailing. Other claimed benefits for the system are that it requires little space, maintenance needs are minimal, and the low harmonic, active front-end inverters mean that current absorption from the generators is almost sinusoidal.
Wind is said to be the first vessel of its type with a large permanently mounted onboard telescopic crane – the crane is an optimised version of the Liebherr LTR 11200, installed in 2010 at the Orskov yard. Instead of installing a separate drive to operate the crane, the Vacon solution uses one of the propulsion drives, that for the bow thruster. This is possible because the crane and propulsion system are never used simultaneously.
Per Kristensen, marine superintendent at DBB says: “The energy consumed by propulsion on the Wind has fallen from approximately 1,100 kW to 800 kW at nominal speed. I am surprised that the energy savings have been that high compared to our previous diesel engine driven solution.”
______________
VACON
www.vacon.com/
www.motorship.com/news101/wind-farm-service-ship-uses-ac-drives
19 Aug 2011
Vacon of Finland has supplied its low harmonic air-cooled AC drives to control the propulsion system and operation of a deck crane on Danish wind turbine service vessel Wind.
Wind is a self-propelled heavy-lift vessel owned by. DBB Jack-Up Services, which is capable of replacing heavy components on wind turbines at a height of up to 100m.
The thrusters used for Wind’s propulsion and DP systems are dynamically controlled by Vacon AC drives. Vacon says that this brings energy savings, because thruster speed can be optimised for the actual speed of the vessel, giving maximum grip on the water. In conventional diesel engine installations speed is adjusted in steps, so that it is often too low or too high, resulting in a looser grip on the water. The torque of the thrusters is monitored closely by the Vacon AC drives to ensure that the thrusters are only operated within the permitted torque range. This is essential when changing the direction of the azimuth thruster unit, for example, since this cannot accept full torque if it is at an angle to the direction in which the vessel is sailing. Other claimed benefits for the system are that it requires little space, maintenance needs are minimal, and the low harmonic, active front-end inverters mean that current absorption from the generators is almost sinusoidal.
Wind is said to be the first vessel of its type with a large permanently mounted onboard telescopic crane – the crane is an optimised version of the Liebherr LTR 11200, installed in 2010 at the Orskov yard. Instead of installing a separate drive to operate the crane, the Vacon solution uses one of the propulsion drives, that for the bow thruster. This is possible because the crane and propulsion system are never used simultaneously.
Per Kristensen, marine superintendent at DBB says: “The energy consumed by propulsion on the Wind has fallen from approximately 1,100 kW to 800 kW at nominal speed. I am surprised that the energy savings have been that high compared to our previous diesel engine driven solution.”
______________
VACON
www.vacon.com/