Energy Exchange Between Unidirectional Vehicle- to-Grid Aggregators, and Wind and Conventional Generating Companies in the Electricity Market

Electric vehicle (EV) aggregator as an individual firm needs to compete with other players in the energy and ancillary service markets. Hence, there is an energy exchange strategy between wind generating companies (WGenCos) and EV aggregators, and conventional generating companies (CGenCos) in the electricity market. The prices and market outcomes could be affected by this strategy, especially when the wind and EV penetration grow. This paper investigates the impact of a power exchange between the EV load aggregators and all generating companies in the single and multiple strategic firms on electricity market equilibria. Two layers are introduced in the electricity market named wholesale layer and EVs layer to investigate this strategy. At the wholesale layer, the strategic firms including EV aggregators, WGenCos, and CGenCos provide the energy and ancillary services in a pool-based oligopolistic electricity market. At the EVs layer, EV owners connect to EV aggregators in order to take part in the market indirectly for obtaining maximum EV energy capacity and optimal charging tariff. The resultant nonlinear equilibrium problem with equilibrium constraints (EPEC) is linearized and then solved by mixed-integer linear programming (MILP). Numerical results and case studies with increasing levels of the EV penetration are provided.