模糊综合评判在接地故障选线中的应用探讨

现行的各种小电流接地故障选线方法利用不同的故障特征量进行处理,所适用的范围不同,检测故障的鲁棒性和精度不一样。由于小电流接地系统的复杂性及单相接地故障的特殊性,每种选线方法往往都有一定的局限性和不足,如果利用信息融合技术对多种选线方法进行综合应用,将不失为一种提高接地故障选线性能的有效手段。针对小电流接地系统中的接地故障选线问题进行研究,提出了针对多种选线方法进行模糊综合评判的小电流接地系统故障选线模式,对多种选线方法的模糊隶属函数及权重因子的确定进行了探讨,以能量函数法、小波变换法及相间工频变化量比较法三种接地故障选线方法为例进行了模糊综合评判实例仿真,仿真结果说明针对多种选线方法进行模糊综合评判的故障选线模式具有更高的可靠性。

Discussion of fuzzy comprehensive evaluation application on earth fault line selection

The existing different grounded fault line selection methods in ineffectively grounded system collect different fault information to deal with. Different methods have the different applicability,and the robustness and accuracy to check out the fault line are also different. Since the complication of the ineffectively grounded system and the characteristics of single-phase grounded fault,each of the methods has some limitations. Therefore,applying comprehensively various methods with information fusion technique,it will be an efficient way to improve the performance of the grounded fault line selection. This paper focuses on the investigation of fault line selection in ineffectively grounded system and presents a mode of fuzzy comprehensive evaluation for multiple methods of earth fault line selection. Membership functions and weight factors of multiple methods including are probed in the paper. The actual example simulations of fuzzy comprehensive evaluation for three methods including fundamental component mutation between phases,energy function,and wavelet transform are done. The results show that this mode has higher reliability.