By Yang Xinming

At 10:18 pm 18 July, at Rudong sea area about 70 km from the coast, as Rudong offshore converter station was floated and installed to jacket structure successfully, the world’s largest and first in Asia offshore converter station was ‘settled down’ successfully. The carbon reducing and green ‘power station’ which weighs about 22.7 thousand tons will combine in total 1100 megawatts electric energy from three major offshore wind farms which are Rudong three gorges H6, H10 and China General Nuclear Power Group H8. It can transport 3.3 billion kilowatt-hours electricity to Jiangsu power grid every year.

Rudong offshore converter station was invested and built by three gorges group and China General Nuclear Power Group together. It is the major core equipment of the first positive and negative 400 kilo-volts flexible direct current transmission offshore wind power project. It is also the offshore converter station with largest capacity, highest voltage and largest size in the world up to now. It includes two parts, which are upper module and bottom jacket foundation. The upper module is 89 m long and 84 m wide. The plane area is close to a standard football field. The height is 44 m, which is about the height of a 15 storey building. The weight is close to the sum of 7 to 8 offshore booster stations.

Large size and amazing weight, how was the offshore installation of the ‘giant’ completed? The contractor used heavy equipment high level float over installation method which was initiated in China. The core of the technology is to make use of the natural power of the tide, use barge to move upper module near the rabbet of the jacket in rising tide, let the upper module be above the jacket naturally, when the tide falls, upper module will drop slowly from high position.