一种基于DA系统适应线路结构动态调整的双向闭锁式保护方法

利用闭锁式保护可以确保配电线路多级保护间的选择性，提高供电可靠性。但已提出的闭锁式保护方案均需要出口断路器参与，未考虑含分支线路以及网络拓扑动态变化等问题。在配网自动化系统基础上提出一种双向闭锁的保护新方法，主站通过查询线路拓扑结构区分线路中各馈线终端单元FTU(Feeder Terminal Unit)角色，重点判断与出口断路器相邻的FTU位于线路首端还是末端。感受到故障电流的各FTU分别向邻居FTU发送闭锁信号，不同角色FTU对应不同判据判断故障区段并切除。该方法不需要出口保护配合，能适应带有单联络与多联络的线路，也能适应多端保护(主干线路与分支线路均配置保护)等复杂情况。通过静模试验分析验证了该算法的选择性与快速性。

A bi-direction blocking protection method based on DA system adapting to the dynamic adjustment circuit structures

Using the blocking protection guarantees the selectivity between multilevel protections of distribution line and improves the power distribution reliability. But the existing blocking protection methods need the cooperation of outlet circuit breakers, and are not suitable for the system with branch lines and network topology with dynamic change. A novel method of bi-direction blocking protection based on distribution automation system is proposed. In this method the master station identifies the position of every FTU (Feeder Terminal Unit) according to the network topology, and mainly determines the FTU adjacent to outlet circuit breakers whether locates at the head or the end of line. The FTU which recognizes the fault current sends blocking signal to their adjacent FTU, and then the FTU of different roles determines the fault location and clears the fault according to different criterions. This method can clear the fault of tie lines and branch lines rapidly and accurately. The selectivity and rapidity are verified by static model test analysis.