一种海上风电场全直流电能汇聚设计方案

A Scheme of Full DC Power Convergence for Offshore Wind Farms

高压直流输电已是海上风电场的首选输电方式。取消海上变电站的全直流电能汇聚是当前海上风电场高压直流输电的发展趋势之一。在直流串并联拓扑结构基础上,提出了一种直流混联矩阵(DC hybrid matrix,DCHM)的拓扑结构。该拓扑结构在不同支路的相邻机组间设有常开电力电子开关,当一方机组停机时,电力电子开关闭合,由相邻的机组承载,明显降低过电压值。在DCHM结构基础上,提出了风电场布局优化设计方案。经仿真验证表明,该方案能降低电气元件采购成本、提高发电效益和风电场可靠性。

HVDC is the preferred transmission mode for offshore wind farms. All DC electric energy convergence without offshore substation is one of developing trend for topology design of offshore wind farms. Based on DC series-parallel topology structure, a DC Hybrid Matrix（DCHM） topology is proposed. The proposed structure has normally open power electronic switch between adjacent units in different branches. During unit downtime due to failure or other factors, the switch can be closed and loads can be transferred to adjacent unit in order to reduce voltage overload. An optimized wind farm layout design is also proposed based on DCHM structure. The simulation results verify the validity of proposed structure. This scheme can also reduce equipment cost and improve electricity generation efficiency.