Game-theoretic approach for smartgrid energy trading with microgrids during restoration

The involvement of self-organizing microgrids to support the distributed network restoration makes the application of centralized power dispatching control led by utility impractical. This paper presents a game-theoretic approach to provide decision support during load restoration on energy price for utility as well as on energy dispatching for microgrids. A two-layer game structure is built to model the interaction between the utility and microgrids. The first layer is the Nash game to formulate the non-cooperative relationship between two self-organizing microgrids. The second layer is the Stackelerg game led by the utility to determine the electricity price during the energy trading with microgrids. The system voltage stability level, which is a critical factor during the system restoration, is counted into the payoff function of each player. Voltage collapse power index (VCPI) is calculated to evaluate the voltage stability level in every time step using a newly-developed line sensitivity factor method to obviate the conventional power flow calculation. The proposed decision making approach is applied in the IEEE 6-bus test system with a different load restoration profile and the effect of considering voltage stability factor on restoration decision-making results is evaluated.