Although the robustness of power grid is increasing

the area through which partial transmission lines pass is vulnerable to icing coating disaster

resulting in a significant increase in the probability of primary fault in the area which

in turn

leading to the secondary cascading fault of power grid. In view of this problem

first

the vulnerability of primary fault of the transmission line due to ice coating disaster is judged by Monte Carlo method. Then

the vulnerability of secondary cascading fault of transmission line caused by the primary faultis judged by self-organizing criticality theory

thus setting up the transmission line vulnerability analysis model considering comprehensively ice coating disaster and physical characteristics of power grid

showing the fault evolution process of power grid under ice coating disaster and providing important decision making for operation and maintenance personnel to identify the weak links of transmission lines in regional power grid under ice coating disaster. Finally

the feasibility of the proposed model is verified by simulation and analysis of an example of the IEEE-39 bus power system.