一起母差失灵保护误动原因的仿真分析

Simulation Analysis of a Busbar Differential Protection Malfunction Reason

通过对某330 kV变电站母差失灵保护误动原因的现场调查、理论分析和仿真模拟分析,从理论层面准确分析和阐述了造成母差失灵保护误动的原因。失灵保护的光隔开入抗干扰措施不完善,抗干扰延时未能起到应有的作用,无法躲过交流混入直流系统后所产生的"干扰",再加上该型号失灵保护开入重动继电器动作功率较低,是造成此次母差失灵保护误动的主要原因。

Through field investigation, theoretical analysis and simulation analysis on the malfunction reason of the busbar differential protection in one of 330 kV substation; the paper accurately analyzes and expounds the malfunction reason from theoretical aspect. Became the Anti - interference measures of Photoelectric Isolation Digital Input of malfunction protection is imperfect, and the Anti - interference delay has not reached the designed effect, thus the interference of AC inputting into DC can not be avoided, besides the power of the malfunction protection inputs into the reinitiated impedance relay is rather low, therefore it＇ s the main reason induced the busbar differential protection malfunction.