To achieve the safe operation of power system and prevent cascading failures, a vulnerability assessment method of power system is proposed based on the state correlation of branch fault. Firstly, a weighted correlation network based on the branch potential energy is established by using the state transition relationship of the two-level cascading failures. Secondly, the vulnerability assessment model of power system is constructed by applying the Theil entropy theory into the weighted correlation network. Finally, the simulation results on IEEE_39 bus system and an actual power system show that the model can not only evaluate the vulnerability of power system effectively but also find the vulnerable branches in power network more accurately.

为了实现电力系统的安全运行并防止级联故障，提出了一种基于分支故障状态相关性的电力系统脆弱性评估方法。首先，利用二级级联故障的状态转移关系，建立了基于分支势能的加权相关网络。其次，将泰尔熵理论应用到加权相关网络中，建立了电力系统的脆弱性评估模型。最后，在IEEE_39总线系统和实际电力系统上的仿真结果表明，该模型不仅可以有效地评估电力系统的脆弱性，而且可以更准确地找到电网中的脆弱分支。