Residential Microgrids Energy Trading With Plug-In Electric Vehicle Battery via Stochastic Games

For microgrids (MGs) with electric vehicle prosumers, effective time-of-use based energy trading is important for multi-vehicles-to-MG system. In this paper, a Stochastic Stackelberg game (SSG) model is proposed. The model is based on the Stackelberg game, where the sellers act as leader and the buyers are considered as follower. First, according to the distributed generation's (DG) output and load distribution, MGs are classified as sellers and buyers, whose strategies set are established separately. Then the utility models of sellers and buyers are established, which include a stochastic variable model for electric vehicles (EVs). Moreover, with the proof of equilibrium and uniqueness of the Stackelberg equilibrium, sellers are obligated to coordinate the sharing of energy with maximization of the profit, while the buyers are autonomous to maximize their utilities with demands response to availabilities. Finally, the game equilibrium is solved to deal with the uncertainty of EV's energy and plugging-in time. By using the collected data from realistic EVs, the effectiveness of the model is verified in terms of seller profit, the utilities of buyers, and the net energy usage in MG. The results of the static pricing model and SSG model were compared to demonstrate the effectiveness of the SSG model.