Design of Grid Independent EV Charging Station

Abstract

Due to pollution-free transportation, Electric vehicles (EVs) have gained popularity in the past few years. However, the major limitation of EVs is charging stations. The DC charging station facilitates the fast charging capability rather than AC as the onboard charger's power is not limited. In most cases, DC charging stations are powered by renewable energy sources like solar and are supported by the AC grid. In this case, maintaining power factor at the source end is a challenging task. I <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$n$</tex> this regard, the paper aims to propose a grid-independent EV charging station. An energy storage device is used to meet the energy demand and improve the sustainability of the charging station. The proposed system possesses a simple design and control strategy. The topology has been deduced by connecting two boost converters back-to-back. A dual active bridge converter has been used between the proposed topology and EV charging point to ensure isolation between the sources and EV port. The topology has been validated in MATLAB/Simulink environment. Nevertheless, the limitation of this topology is that the output voltages of both the boost converters must be equal. Therefore, a controller has been designed to regulate the DC output voltage.