Distribution network fault studying and judging method and system based on sudden reduction degree of feeder current and probability density of the proportion of switch loads

The invention relates to the technical field of power distribution network automation, and discloses a distribution network fault studying and judging method and system based on the sudden reduction degree of feeder current and the probability density of the proportion of switch loads, so as to improve the real-time performance and reliability of fault positioning. The method comprises the following steps: monitoring the sudden reduction degree of current at the outlet of a feeder line in real time, determining that a fault occurs when the sudden reduction degree is greater than a certain threshold value, and recording the fault occurrence time and the sudden reduction degree of the current of the feeder line; then, mapping into a pair of binary coordinates, and searching a load proportion probability density table (curve) of each switch in the line according to the coordinates; one or more switches with the maximum probability density being judged as tripping switches. 本发明涉及配电网自动化技术领域，公开一种基于馈线电流骤减度和开关负荷占比概率密