A Study on the Adequate Capacity of Substation Transformer for Offshore Wind Farm

해상풍력발전단지의 해상변전소 변압기 적정 용량에 관한 연구

Moon, Won-Sik;Jo, Ara;Huh, Jae-Sun;Bae, In-Su;Kim, Jae-Chul

  • Received : 2015.06.22
  • Accepted : 2015.07.06
  • Published : 2015.08.31


This study suggests the methodology to decide the number and adequate capacity of substation transformer in a large-scale offshore wind farm (OWF). The recent trend in transformer capacity of offshore substation is analyzed in many European offshore wind farm sites prior to entering the studies. In order to carry out the economic evaluation for the transformer capacity we present the cost models which consist of investment, operation, and expected energy not supplied (EENS) cost as well as the probabilistic wind power model of wind energy that combines the wind speed with wind turbine output characteristics for a exact calculation of energy loss cost. Economic assessment includes sensitivity analysis of parameters which could impact the 400-MW OWF: average wind speed, availability, discount rate, energy cost, and life-cycle.


Economic Evlauation;Offshore Substation;Redundancy;Sensitivity Analysis;Transformer Capacity


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Supported by : 기초전력연구원