Abstract: Under the traditional mode, the planned maintenance and emergency repair are adopted in the power distribution station,in which the decision-making is rigid with obvious lagging disadvantages. Based on the data of the current LV power distribution network,by means of calculation of the user loop impedance,this paper proposes a model to fully sense and evaluate the line state of the transform area,so as to support the transformation of the maintenance mode. First, the impedance equation of the user loop is established by simplifying the network topology,and the impedance of the user loop is calculated using the constrained linear least square model. Second, considering the relationship between line impedance state and fault type,the decision model of random fault and cumulative fault states of the line in the transformer area is proposed innovatively. Furthermore, the operation effectiveness evaluation model considering the maintenance cost is constructed, and with the objective of maximizing the operation effectiveness,combined with the constraints of power supply reliability,the optimization model of the maintenance decision of the transformer area is established based on a nonlinear programming method. Finally,the effectiveness of the proposed model and algorithm are verified by taking the power supply station covering 376 common transformers as an example.