Energy Management Model for an Electric Vehicle Charging Station in the Environment of a Microgrid

This work addresses an energy management model of a charging station for electric vehicles (EVs), considering a residential microgrid with the ability of interconnecting to a distribution network. Components of distributed energy resources consist of photovoltaic solar generation (PVSG) and a Battery Energy Storage System (BESS) with bi-directional energy flow capacity. The modeling of the profile and energy consumption associated with EVs was developed based on real data from a fleet of electric taxis. A novel model is presented which represents the EV battery charging system based on its State of Charge (SoC) and its variability in current and charging time. Additionally, electricity consumption profiles of residential users in Quito- Ecuador are considered and modeled. Regarding the design of the PVSG system, records of meteorological stations have been taken into account and, through a statistical-probabilistic analysis, the typical radiation and temperature profiles in the city of Quito are determined. With this, through simulations, the energy produced by the PVSG system was established efficiently managing the energy and the storage in a BESS, allowing thus, nightly charging of EVs for different SoC scenarios. Modeling, analysis, and simulations were performed through the QuasiDynamic in PowerFactory DIgSilent. Results show how an EV charging station can be efficiently managed in the environment of a residential MG through PVSG and BESS.