基于广域零序分布电压特征的小电流接地选线方法

发布时间：2018-08-30 20:59

【摘要】：传统小电流接地选线装置准确性易受系统不平衡电流、电流互感器一致性差异等因素影响。为此提出一种基于广域零序电压分布特征的单相接地故障选线新方法。利用电网的分布参数模型分析得到了配电网发生单相接地故障后不同线路零序电流的分布特征,并据此归纳、推导了配电网不同接地方式下的零序电压的沿线分布特征。由于故障线路与健全线路间零序电压的分布特征存在差异,文章构造了故障测度因子作为选线判据,并通过引入能够描述故障与健全线路差异度、健全线路相似度的相对故障测度矩阵和投票机制来减小故障距离、过渡电阻和脱谐度对选线结果的影响,从而提高选线结果的可靠性。利用PSCAD建立了符合配电网线路分布参数特征仿真模型,仿真计算结果表明,在不同的接地方式、故障距离、过渡电阻和较小的脱谐度情况下,该方法均能正确选出故障线路。
[Abstract]:The accuracy of the traditional low current grounding line selection device is easily affected by the unbalanced current of the system and the uniformity difference of the current transformer. In this paper, a new method of single phase grounding fault line selection based on wide-area zero-sequence voltage distribution is proposed. The distribution characteristics of zero sequence current of different transmission lines after single-phase grounding fault in distribution network are obtained by using the distribution parameter model, and the distribution characteristics of zero sequence voltage along the distribution network under different grounding modes are deduced. Because of the difference in the distribution characteristics of zero-sequence voltage between the fault line and the perfect line, the fault measure factor is constructed as the criterion of line selection, and the difference between the fault line and the perfect line is described by introducing the fault measure factor. The relative fault measurement matrix and voting mechanism of line similarity are improved to reduce the influence of fault distance, transition resistance and detuning degree on the line selection results, thus improving the reliability of line selection results. The simulation model of distribution parameters of distribution network is established by using PSCAD. The simulation results show that the method can correctly select fault lines under different grounding modes, fault distance, transition resistance and lower detuning degree.
【作者单位】：中国矿业大学物联网研究中心;中国矿业大学信电学院;国网徐州供电公司;
【基金】：国家自然科学基金项目(51504253) 江苏省自然科学基金项目(BK20161185) Project Supported by National Natural Science Foundation of China(51504253) Natural Science Foundation of Jiangsu Province(BK20161185)
【分类号】：TM862

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