Abstract:In view of the problems that the existing failure rate calculation models can not take into account the influences of both equipment operation status and grid structure on the equipment failure rate at the same time, and that the risk assessment model of distribution network cannot effectively reflect the real-time state of equipment, a real-time risk assessment method for the distribution network based on the comprehensive failure rate is proposed in this paper. The new method takes into account the synergy between the main fault factors to improve the original state evaluation model. The accurately calculated equipment failure rate is taken into the real-time failure rate model based on a health index, and the undetermined coefficient is obtained by fitting. The failure rate of the equipment under the influence of gradual factors is calculated according to the on-line monitoring data. According to the real-time intensity of the sudden factors in the environment of the distribution equipment to be evaluated, as well as the equipment level and grid structure level,the sudden potential failure rate and comprehensive failure rate are calculated. The feeder partition method is used to calculate the real-time outage probability and risk of each load point, and the weak links of distribution equipment and load points are found through the analysis of an example in the city of Guangzhou.