一种小电流接地系统故障定位新方法

A new method of fault location for small current grounding system

针对小电流接地系统故障定位难的问题,提出了一种利用暂态零模功率的馈线自动化系统故障定位新方法。该方法利用故障位置同侧两点的暂态零模功率波形相似,相关系数接近于1;而故障位置两侧两点的暂态零模功率初始极性相反、波形差异大、相关系数接近于0这一特征。通过求取的相关系数值与阀值进行比较,若大于阀值,判为健全区段;若小于阀值,则为故障区段。得出了不同电压初相角与不同过渡电阻时的相关系数值。通过求取相关系数的最大值,避免了FTU数据采集不同步引起的计算误差。ATP仿真验证了该定位方法的有效性。

A new method of fault location was proposed which utilized the transient zero-mode power when the fault occurred. The waveform of transient zero-mode power is similar at the ipsilateral two point of fault point, and the correlation coefficient is close to 1 ; but the initial polarity of transient zero-mode power is opposite at the two sides of fault point, so the correlation coefficient is close to O. The value of correlation coefficient is compared with the threshold value, if it is greater than threshold value, the section is determined with health; on the contrary, it is determined with fault section. Besides, the error, which caused by the non-synchronized data acquisition, was avoided through calculating the maximum correlation coefficient. The validity of this method was proved by the ATP simulation.