一种复合型微机小电流接地选线装置研制

A complex ground fault line selection device in small current neutral grounding network

目前应用的小电流接地选线装置大多存在选线结果准确率不高、适应性不强的缺点。为了大幅度提高选线装置的选线准确率及适应性,在同一硬件平台基础上,将几种利用零序电流基波的选线方法,如群体比幅比相法、有功分量法和残流增量法等有机结合在一起,构成复合型小电流接地选线装置,运用模糊综合决策,选出故障线路;并给出了选线装置的软硬件设计。实验室模拟电网试验和现场挂网结果表明,装置运行稳定,选线准确,适应性强;不仅适用于中性点不接地电网或经电阻接地电网,而且适用于中性点经消弧线圈接地电网,具有良好的推广应用前景。

Nowadays a few of disadvantages are found in most of applied ground fault line selection devices, such as low accuracy and weak adaptability. In order to increase the accuracy and adaptability of fauh line selection, some methods of fault line selection applying the fundamental component of zero-sequence current, such as zero-sequence current colony amplitude and phase comparison method, zero-sequence current active components method and zero-sequence current increment method, were integrated to constitute a complex device, which may be based on the same hardware structure. The device can accurately select fault line by using fuzzy control theory. Software and hardware design and electromagnetic compatibility design were given. Experimental result and actual operation of the developed device verify its stabilization and applicability. The device may be applied not only in neutral point unearthed network but also in neutral point earthed via arc-suppression coil network, and has good application prospect.