Reliability Evaluation and Optimization Design of DC Collection Based Large-Scale Offshore Wind Power Plants

DC collection based offshore wind power plants (WPPs) have received widespread attention due to their small platforms and high transmission efficiency. On the basis of analyzing the topologies and operation modes of DC collection systems, this paper proposes quantitative reliability evaluation indexes - capacity availability and expected lifecycle electric power income not supplied, and their calculation methods. Then, a gigawatt offshore WPP is designed based on a Chinese offshore WPP, and the impact of the main parameter design on equipment cost and reliability of the DC wind turbine is evaluated. Finally, an optimization design scheme for the main parameters is proposed to achieve economic operation of the power collection system.