基于配电自动化系统的配电网单相接地故障定位技术的工程应用

Engineering Application of Distribution Network Single Phase Grounding Fault Location Technology Based on Distribution Automation System

中国配电网普遍采用中性点非有效接地方式,这种接地方式供电可靠性较高,在发生单相接地故障后,仍可持续运行1～2 h。但是由于其故障电流微弱以及故障点不易燃起电弧等原因,如何准确地进行故障选线和定位一直是一个未解的难题,特别是针对单相高阻接地故障,故障电流和电压变化量往往不能使保护动作,甚至传统的检测方法根本无法识别该故障,也无法进行有效地特征辨识。介绍了"基于配电自动化系统的配电网单相接地故障定位技术研究与应用"项目研究的新技术在龙岩地区开展试点建设的情况及现场实际实验结果;通过对实验中故障电流波形的收集及实验结果的分析,验证了该技术的准确性和可行性,为今后单相接地故障的深化研究提供了有力的数据。

The low-current grounding method is widely used in the neutral point of China's low-voltage distribution network.This grounding method has the advantages of high reliability of power supply.However,after a single-phase earth fault occurs,single-phase earth fault line selection and fault location have not been well resolved for a long time due to weak fault currents and arc instability,especially for single-phase high-resistance earth faults.The voltage and the amount of voltage change often do not enable the protection action,and even the traditional detection method cannot recognize the fault at all.and it cannot perform effective feature identification.This paper introduces the new technology developed in the research and application of single-phase earth fault location technology based on distribution automation system in Longyan area and the actual experimental results.Through the collection of the fault current waveform in the experiment and the analysis of the experimental results,the accuracy and feasibility of the technique are verified,which provides powerful data for the further study of the single-phase ground fault in the future.