The substation is one of the most technical complex units within each Offshore-Windfarm project. Beside collecting electrical energy of the offshore wind turbines, the substation is the central connection point to the grid to transport the electrical energy further through the transmission grid. This is also where the electric current is transformed to the voltage of the grid.
General contracting partner GE is responsible for the design and building of two identically constructed substations for the connection of 40 wind turbines each. Both substations are located at Taiwanese West coast in Yunlin County, close to the offshore windfarm; one is located in Taixi Township and the other one in Sihu Township. Each substation consists of basement, first, second and third floor, where, in addition to four 66/161-kV power transformers, operating, maintenance and meeting rooms as well as the protection, communication and control equipment are located.
The technical equipment of the substation prevents disturbances from affecting the operation of the wind farm and its facilities, even if one of the transformers should fail.
The grid connection of Yunlin Offshore Windfarm is designed to connect to two grid connection points, TPC Taixi Distribution Substation in the North and TPC Sihu Distribution Substation in the South. The energy from the windfarm is transmitted to two wind farm substations, then connect to the two grid connection points with two sets of 161kV power cables, each being approximately 4 kilometers in length.