直流串并联海上风电机组控制策略

Control strategy of DC parallel-series offshore wind turbines

以VSC-HVDC技术为基础,提出了海上风电场直流并串联拓扑结构。此结构可以采用简化结构的永磁直驱风机,具有直流升压的优势,减少了变压站和换流站所需的海上平台建设,也减少了变压和换流过程中的损耗,降低了系统复杂度,减少了建设成本,有利于系统维护。同时此结构在一定程度上解决了风机串联结构和并串联结构中故障所造成的系统波动和支路环流的问题。提出了针对直流串并联结构的协调控制策略。最后通过软件仿真验证该结构的稳定性和控制策略的有效性。

This paper proposes a DC parallel-series topology structure for offshore wind farm based on the VSC-HVDC technology. It uses permanent magnetic synchronous generator wind turbines with simplified structure, which has the advantage of DC boost, decreasing the required offshore platform construction that the substation and converter station needed, reducing the losses occurred during commutation and transformer process, reducing the complexity of the system, construction costs and being conducive to system maintenance. Also, this structure to some extent solves the problems of system fluctuations and branch circulation caused by wind turbine faults in DC series system and DC series-parallel system. Therefore, this paper presents a coordinated control strategy for DC parallel-series structure. Finally, the stability of this structure and effectiveness of the control strategy are validated through the software simulation experiments.