Identification of vulnerable lines in power grids with wind power integration based on topological potential

Abstract

Vulnerable transmission lines are one of the weak links in the operation of the power system, as their damage can trigger widespread blackouts and cascading failures. The integration of large-scale wind power generation into the grid has resulted in significant changes to both the topology and distribution patterns of power flows inside the system, exacerbating line vulnerabilities. Identifying these lines can enhance power system safety through vigilant monitoring or augmenting their carrying capacity. In this paper, a method for identifying vulnerable lines based on the theory of topological potential is proposed. The method is based on the N-1 fault model of optimal DC power flow, and a corresponding network is constructed for the power system. The task of pinpointing weak points in a complicated network is converted into an assessment problem of important nodes. The proposed index comprehensively considers the in-degree and out-degree topological potentials of nodes, and uses the entropy weight method for weight allocation. Meanwhile, the TLS distribution is used to fit the wind power prediction error. Finally, simulation experiments are conducted on the IEEE 39-bus system. Simulation results indicate that the most vulnerable transmission lines tend to be located at the hubs of the system’s topological network and in close proximity to wind farms. • The proposed method maps the power system into a complex network using an N-1 contingency model. • To better reflect the real situation of the power grid, the method adopts optimal DC load flow dispatch. • To consider the uncertainty of wind power output, the method utilizes TLS distribution to fit the error of wind power output. • Simulation results indicate that lines near wind farms and topological hub structures are often most susceptible to faults.

Topics & Concepts