适用于海上风电的多端口直流变电站及其主从控制策略

摘要

This paper first proposes the topology of multi-port DC substation,and creates its mathematical model.The substation can not only achieve the interconnections of different types of offshore wind farms and HVDC systems with multi-voltage levels,but also implement a centralized DC power flow regulation.Then the multi-port DC substation is applied to offshore wind farm integration with multi-voltage levels,and its master-slave control strategy is proposed.The strategy takes advantage of each port of the DC substations to achieve the stable operation during wind power fluctuation or faults at any port of the substation.Finally,a simulation model of a multi-terminal DC test system is established in the PSCAD/EMTDC simulation platform.Steady-state simulation and fault simulation are performed to validate the proposed strategy,and the results show that the strategy can ensure the stable and reliable operation of the multi-port DC substation. The work is supported by National High Technology Research and Development Program of China (863 Program) (No.2012AA050208) and Program of Introducing Talents of Discipline to Universities (“1 1 1" Program)(No.B08013).%提出多端口直流变电站的拓扑结构，并建立了相应数学模型；该变电站可以实现不同类型、多电压等级的多送端海上风电场和多受端高压直流输电系统的互联，并实现直流潮流的集中调控。将多端口直流变电站应用于多电压等级海上风电并网，并提出多端口直流变电站的主从控制策略，利用直流变电站各端口的协调实现风功率波动时或任一端口故障时变电站的正常工作。最后，在PSCAD/EMTDC 仿真平台中搭建了含多端口直流变电站的多端直流试验系统仿真模型，并针对所提出的主从控制策略进行了稳态仿真分析和故障仿真分析，结果表明该策略能够保证多端口直流变电站的稳定可靠运行。