Security Margin Assessment Method of Centralized Spot Market Based on Information Entropy

Abstract

In the centralized spot market, each participant pursues the maximization of economic benefits, which leads to the operation condition of the power grid closer to the security boundary. Thus, in this paper, a novel approach to security margin assessment of the centralized spot market is proposed. By proceeding from the mechanism of influence of load variation on power flow, the relationship between power flow transfer characteristics and the security margin of the power grid is explored. Then, on the basis of information entropy theory, the power flow transfer balancing evaluation index of the power grid is established. And this index is applied for security margin assessment of the power grid in the environment of the centralized spot market. Results of an IEEE 14-bus system case study have validated the effectiveness and quickness of the proposed method. Meanwhile, in accordance with the analysis results, it is proved that the proposed method is capable of accurately identifying the critical power transmission and transformation equipment affecting the security margin of the power grid, which is helpful to identify the potential risks of the operation of the power grid in advance.