Distribution network single-phase disconnection fault positioning method

The invention discloses a distribution network single-phase broken line fault positioning method. The method comprises the following steps: (1) judging whether a broken line fault positioning analysis process is carried out or not based on the three-phase unbalance degree of the low-voltage side of a distribution transformer in a distribution network; (2) defining each transformer substation in the distribution network as an abnormal distribution transformer and a normal distribution transformer based on the three-phase unbalance degree of the low-voltage side of the distribution transformer in the distribution network in a broken line fault positioning analysis process; and (3) marking a normal distribution transformer and an abnormal distribution transformer on the basis of the distribution network line topological graph, wherein a line between the normal distribution transformer and the abnormal distribution transformer is a broken line fault position. In the step (1), when it is detected that any transfor