Vulnerability assessment of bulk power grid based on complex network theory

The vulnerability assessment algorithm of the bulk power grid based on complex network theory is proposed in this paper. The traditional research model of the power grid based on complex network theory is a graph with no direction and no weight at present. Because this model is far from the real power system, sometimes the wrong results may be gotten. In this paper, the models of components in the power grid are constructed detailedly, furthermore the weighted and directional graph is provided. First, the connecting formings among buses (instead in the traditional methods only substations are considered), lines, transformers and generators are simulated detailedly. Second, the power flow direction in the power grid is considered, and the components' tolerance to disturbances is also considered. Based on the proposed model, the power grid's tolerance to errors and attacks is analyzed. The key components and weak areas are indicated. At last, the robustness and fault dissemination mechanism of the power grid under cascading failures are analyzed based on the proposed method. The North China power grid is used as an example to validate the proposed method.