大规模新能源直流外送系统调相机配置研究

针对抑制送端电网暂态过电压的技术需求，首先分析了送端电网暂态过电压的影响因素；然后构建了直流外送试验仿真系统，基于机电暂态仿真，考虑分布式调相机及其分层分散配置的作用，分别提出了调相机集中和分散接入不同电压等级配置方案；最后通过对比各方案给出了大规模新能源直流外送系统调相机配置建议，研究结果表明在各新能源汇集站低电压等级侧分散配置小型化调相机，不仅可以全面解决送端系统的暂态过电压问题，还能进一步提高经济性。

Research on synchronous condenser configuration of large-scale renewable energy DC transmission system

In view of the technical requirements for suppressing transient overvoltage of power grid at sen-ding end, firstly the influencing factors of transient over-voltage of the power grid at sending end are analyzed. Then a test system of DC transmission is established, based on electromechanical transient simulation, considering distributed synchronous condenser and decentralized hierarchical configuration, the synchronous condenser configuration scheme of centralized and decentralized accessing to different voltage levels are separately proposed. Finally, by comparing different schemes, the synchronous condenser configuration suggestions for large-scale renewable energy DC transmission system are given. The simulative results show that the decentralized configuration of synchronous condenser at low voltage side of each renewable energy collecting stations can not only solve transient over-voltage problem of the sending end, but also further improve the economy.