地铁直流牵引供电系统中的DDL保护

分析了地铁直流牵引供电系统中几种常用的馈线保护类型,发现现有的保护方法很难避免跳闸保护拒动或误动现象的发生,并且不能保护馈线的全长。以电流上升率保护和电流增量保护为基础,提出了一种新型的DDL保护方法及整定原则,并推导出了完整的动作方程。该方法有效地避开了列车启动电流的影响,不但可以迅速切除近端的短路故障,而且通过延时跳闸还可以切除远端短路故障。仿真结果表明该方法设计合理,切实可行。

DDL Protection in Subway DC Traction Power Supply System

After analyzing several kinds of protection for feeder line in subway DC traction power supply system,it is pointed out in the paper that the phenomena of refusing action and error action can not be avoided with existing protection which can not protect the whole feeder line.Based on the current-rising-rate protection and current increment protection,the principle of DDL protection as well as its action equation is presented.The nearby fault can be cleared immediately while the distant fault can be cleared with a delay by using the proposed method which will not be influenced by the starting current of trains.The feasibility and rationality of the method are proved by the simulation results.