三峡近区电网短路电流限制措施研究

Research on Measures of Limiting Short-circuit Current in Power Grid near Three Gorges

目前,三峡近区部分站点的短路电流已经超过其断路器的遮断容量,成为制约三峡近区电网进一步发展的关键因素。在回顾三峡输电系统构建过程中短路电流优化方案的基础上,结合三峡近区电网的结构特点、三峡机组间的小干扰稳定特性,提出了加装串联电抗器、背靠背联网、特高压分母、优化电网结构、调整运行方式5类短路电流限制措施,并研究了各类措施的限流效果和实用性,推荐了不同网架方案下三峡近区电网的短路电流解决方案。

Short-circuit current exceeding the allowable capacity of breakers is a critical constraint for developing the power grid near Three Gorges.Combining the structure features of the grid near Three Gorges and the small signal stability of generators,the paper proposes the measures for limiting the short circuit current,including series reactor installing,back to back HVDC connection,UHV bus segmented,optimizing the grid structure and adjusting the operating mode,discusses the effect and practicability of the limiting measures,and recommends the solution for limiting the short circuit current under different power grid structure near Three Gorges.