智能配电网单相接地故障区间智能定位方法设计

Design of Intelligent Positioning Method for Single-Phase Grounding Fault Interval in Intelligent Distribution Network

针对当前故障区间定位受到阻抗模值持续增大影响,导致区间定位结果不精准的问题,设计了智能配电网单相接地故障区间智能定位方法。根据阻抗模值变化的特点,构建阻抗模值区间数据库,模拟相邻节点同类型故障情况,划分智能配电网单相接地故障区间。计算故障发生时三相电流的增量,获取故障区间总电流,采用差分滤波法计算零序电流,通过判断零序电流与设定启动阈值之间的关系,实现接地故障区间智能定位。结果表明,该方法分析的故障后零序电流波形与实际波形变化一致,且定位耗时最短(9 min),具有精准的定位效果。

Faced with the problem of inaccurate interval positioning results due to the continuous increase in impedance modulus value,an intelligent single-phase grounding fault interval positioning method for intelligent distribution networks has been designed.Based on the characteristics of impedance modulus changes,construct an impedance modulus interval database,simulate the same type of fault situation in adjacent nodes,and divide the single-phase grounding fault interval of the intelligent distribution network.Calculate the increment of three-phase current when a fault occurs,obtain the total current of the fault interval,use differential filtering method to calculate the zero sequence current,and achieve intelligent positioning of the grounding fault interval by judging the relationship between the zero sequence current and the set starting threshold.The results show that the zero sequence current waveform analyzed by this method is consistent with the actual waveform changes after the fault,and the positioning time is the shortest(9 min),with accurate positioning effect.