Solar powered grid integrated charging station with hybrid energy storage system

Abstract

To overcome the deficiency in fossil fuels and their environmental effects, the popularity of the integration of renewable energy sources and the adoption of electric vehicles is growing day by day. But high pricing and a lack of available charging stations are impeding EV adoption. Also, the weather-dependent RES power generation creates demand and generation disparity in a microgrid system. Hence, energy storage technology integration is crucial to increase the possibility of flexible energy demand with the charging of EVs and ensure that extra generated power can be stored for later use. In this proposed EV charging architecture, high-power density-based supercapacitor units (500−5000W/L) for handling system transients and high-energy density-based battery units (50−80Wh/L) for handling average power are combined for a hybrid energy storage system. In this paper, a power management technique is proposed for the solar-powered grid-integrated charging station with hybrid energy storage systems for charging electric vehicles along both AC and DC loads. For the charging of electric vehicle batteries, the stepwise constant current control charging method is proposed in which the charging current will decrease with an increase in the state of charge of vehicle batteries. The performance efficacy of the proposed system is confirmed through both MATLAB/Simulink and OPAL-RT simulation.