An Improved Energy Management Strategy for a DC Microgrid Including Electric Vehicle Fast Charging Stations

Abstract

Growing world concern over greenhouse gas emission, the promises of efficient energy, the development of battery characteristics and falling of its prices have led to the rapid increasing adoption of EVs. The number of electric vehicles (EVs) on the road is expected to continue to increase during the next decades due to various factors such as the rapid progress in EV technology and decreasing battery prices The prolonged battery charging process, which is one of the main problems that affects the increased EV penetration, makes the fast-charging units more attractive and efficient option for the charging stations. In this study, a control strategy for a DC microgrid including electric vehicle fast charging station (EVFCS) and distributed generation units is presented to examine the impacts of EVFCS on the grid as well as their potential contributions to the system operation in the case of considering the vehicle-to-grid (V2G) technology. It is especially aimed to mitigate the voltage sag and swell problems by using the EV battery as a DC source of a distribution static compensator (D-STATCOM) device. Simulation studies in MATLAB Simulink/Sim Power systems show that considerable improvements can be achieved from the perspective of distribution system operation such as improved voltage quality and from the perspective of end users such as decreased charging durations.