1.Department of Electrical Engineering, Tsinghua University, Beijing 100084, China;2.State Key Laboratory of Control and Simulation of Power System and Generation Equipments,Tsinghua University, Beijing 100084, China;3.State Grid Jiangsu Electric Power Co., Ltd., Nanjing 210024, China
This work is supported by State Grid Corporation of China(No. SGJS0000DKJS1900265).
The vulnerability assessment of transmission branch lines is an important step in the subsequent analysis and prevention of cascading outages. Existing vulnerability indices have problems including unclear physical meaning, lacking consideration of the impact of multiple outages on vulnerability. To address the issues, this paper constructs a cooperative game framework of transmission branch lines. According to the game result, the loss caused by a fault chain is distributed properly to each branch line as their vulnerability indices. The indices can reflect the contribution of the fault on branch lines to the power grid loss caused by the outage accidents, and its physical meaning is clear. To solve the problem of the non-superposition of the loss of mutiple fault chains, the corresponding multi-objective optimal programming is transformed into a two-stage optimization model with collective and individual rationality. The two-stage optimization model uses genetic algorithm and linear programming respectively. The case study of IEEE 39-bus system verifies the validity of the proposed index.