基于S-粗集的小电流接地故障选线研究

针对基于小波包分析的小电流接地故障选线方法的缺点，提出了基于S-粗集的小电流接地故障选线方法.由于对零序电流信号的采样频率较低，使故障线路集合中的元素迁移到健全线路集合中，导致错误的选线结果.通过构造一个元素迁移函数，使迁移出的元素回到故障线路中，从而获得正确的选线结果.仿真结果表明，该方法有效地提高了小电流接地故障选线的精度.

Study on fault line detection based on S-rough sets in indirectly grounding power system

After analyzing the deficiencies and advantages of the fault line detection method based on wavelet packet in indirectly grounding power system,a novel fault line detection method based on S-rough sets(singular rough sets) was proposed.Because the sampling frequency of the zero sequence current signals was too low,the elements of the fault line set were transferred into the sound line set and the results of fault line detection were wrong.The elements transferred can return to the fault line set through constructing an elementary transfer function and the right fault line detection results were achieved.The simulation results show that this method has effectively raised the accuracy of the fault line detection in indirectly grounding power system.