适用于直流配电网母线保护的改进方法

当直流系统的母线发生故障时,故障电流迅速上升,目前直流配电网母线保护基本引用了交流保护方案,动作时间较长,不利于直流故障的快速隔离。为保证经济性的同时,实现在直流配电系统母线故障时的可靠快速保护,首先对直流配电网母线故障特性进行分析,然后对直流配电网母线保护接线方案、保护算法、资源配置进行改进,提出了差流直接通过直流互感器采集、采用电流变化率算法、分级处理数据、使用不同形态出口继电器等方法。通过实时数字仿真仪进行仿真分析,验证了所提方法的有效性,该方法在兼顾经济性同时可以有效提高直流配电系统母线保护的可靠性和快速性。

Improved method for busbar protection in DC distribution network

When a bus short circuit fault occurs in DC system, the fault current will rise rapidly. At present, the bus protection of the DC distribution network basically refers to the AC protection scheme.and the operation time is long, which is not conducive to the rapid isolation of the DC fault. In order to achieve reliable and fast protection of bus faults in DC distribution systems while ensuring economy , firstly the fault characteristics of the bus distribution of the DC distribution network are analyzed, and then the bus protection wiring scheme, protection algorithm and resource allocation of the DC distribution network are studied This paper also proposes methods or recommendations for differential currents to be directly collected by DC transformers, using current rate-of-change algorithms, hierarchically processing data, and using different exit relays and so on, which the effectiveness is verified by the real time digital simulator (RTDS). The proposed method can effectively improve the reliability and rapidity of bus protection of DC power distribution system as well as balancing economics.