站域保护可方便获取站内电气量,因此提出一种基于有限交叠多分区的站域后备保护方案。根据作用域范围将站域划分为母线-线路融合区、母线-变压器融合区、多元件协同融合区3类有限交叠分区。根据各分区可能出现的故障情况,设计了每个分区的动作方案。当站域范围内发生故障且主保护拒动时,通过不同的有限交叠分区之间的协调配合,可选择性地快速隔离故障。实际变电站故障案例分析结果表明,该方案解决了传统阶段式后备保护动作时限长的问题,有效改善了高中低压元件的后备保护性能,简单灵活、可靠性高。
Since the electrical variables of substation can be easily obtained,a substation backup protection scheme based on multiple limitedly overlapped divisions is proposed,which divides the substation zone into multiple integration divisions based on three types :bus-line,bus-transformer and multi-component. Operation schemes are designed for each division according to its probable faults. When an in-zone fault occurs while the main protection does not act properly,the fault can still be isolated selectively and quickly by the coordinated actions among multiple divisions. The case analysis of an actual substation fault shows that,compared to traditional multi-stage backup protection,the proposed simple scheme has shorter time-limit and higher reliability,which effectively improves the performance of backup protections for HV and MV components.