基于数学形态学的配电网单相接地故障暂态选线算法

Transient Algorithm for Single-line to Ground Fault Selection in Distribution Networks Based on Mathematical Morphology

分析了单相接地故障选线的现状和目前已提出的多种选线算法的优势和不足,提出了基于数学形态学的暂态选线新算法。算法包括两方面:一方面,利用组合形态滤波器对选线数据进行滤波预处理,最大限度地去除噪声对选线的影响;另一方面,利用形态学算子对去噪后的信息进行暂态突变检测以确定故障线路。仿真结果表明,该算法设计简单,计算量小,并且克服了故障信号信噪比低的缺点,可以通过选择合适的结构元素准确可靠地确定故障线路。

After the analysis and comparison of the present single-line to ground （SLG） selection techniques, this paper proposes a novel transient approach based on the mathematical morphology for the SLG selection. It consists of two steps： the combined morphological filter is first developed to filter noise in transient zero-sequence voltages and currents in order to reduce the impact of noise on the selection, and the proper morphological structure elements are then applied to detect transient break points for selecting the grounded line. The simulation results show that the proposed approach can overcome the deficiency of low signal noise ratio with features of easy implementation and fast speed. The faulted line can be detected fast and accurately by choosing proper morphological structure elements.