Grid-Oriented Coordination Strategy of Prosumers Using Game-theoretic Peer-to-Peer Trading Framework in Energy Community

In this paper, a grid-oriented peer-to-peer (P2P) energy transaction strategy based on game theory that considers participants with diversity in trading and the impact on the system of trading is studied. For this, the optimization problem of prosumers with ESS is defined according to the lifetime cost of the ESS. The proposed energy trading strategy is carried out based on three game theories. Among them, the evolutionary game between buyers, non-cooperative games between sellers, and Stackelberg games between sellers and buyers are considered. When all games are played sequentially and the convergence point is reached, the negotiation is determined and then ends and a contract is made based on trading price and amount. As a novel contribution in the case of the evolutionary game the community manager indirectly provides information on the system so that when evaluating the seller, the effect on the system is applied as a loss change. In addition, when deriving a utility value by payoff, it is set as an increase/decrease ratio compared to the initial value so that the game proceeds regardless of the size of the participants and the defined problem. To verify the effectiveness of the proposed P2P energy trading strategy, a simulation based on MATLAB is performed. It is confirmed that the effect on the grid is applied to the seller's selling price. When the strategy proposed in the P2P energy trading is applied, the increased purchase and selling amount due to the trading increased by 3.41 % and 4.51 %, respectively, he difference between increased puchase and selling amount decreases by about 36 % from 3.181 kW to 2.03 kW, and the loss due to the change in trading amount also decreased by 1.59 %. This means that the grid impact has been reflected in the P2P energy trading, resulting in efficient operation, and it is the reason for grid operators to accept P2P energy trading. In conclusion, the results of the proposed strategy prove that efficiency in energy use is increased by considering the impacts of the power system in P2P energy trading.