Charging strategies to minimize the energy cost for an electric vehicle fleet

In the paper, we consider the charging scheduling of the electric vehicles (EVs) at a charging station with multiple charge points. The charging station is equipped with photovoltaic (PV) generator and can buy or sell energy to power grid. The paper proposes charging strategies to reduce the charging cost of the charging station under time-varying electricity price signals. These strategies are based on the interruption (on/off) or on the modulation of EV charging power. By dividing the daytime in many intervals, a binary linear programming and a linear programming is used, respectively for each strategy, to manage the charging plan of the vehicles. The first application is used for reducing total energy cost in daytime. The second application is proposed to limit the charging power and reducing total energy cost simultaneously during a time defined by DSO (or another operator). The proposed method takes into account the random time arrival and random time departure of vehicle. The performance of the proposed strategies is validated by simulations for a charging station of 50 electric vehicles in real time conditions.