Implementation of DC Micro Grid Tied PV-Storage Based EV Fast Charging Station

Installing new DC fast-charging stations especially alongside motorways is of great importance to meet the energy demand of a huge number of EVs in the near future. In this paper, a novel DC microgrid tied PV/storage system is purposed for EV fast chargers in which the power is supplied by large-scale PV arrays and storage systems through phase shift full bridge (PSFB) converter with minimum need of AC grid supplement. In this system, a phase shift full bridge (PSFB) is employed to boost the common voltage of the PV/storage system to higher values rather than connecting a large number of cells (PV and storage) in series to reach a high level of voltage which will consequently increase the reliability and redundancy of PV and storage system specifically for medium voltage (MV) DC grids. Moreover, the PSFB converter provides galvanic isolation between the storage and AC grid if there is a need to connect PV/storage system directly to the AC grid (without a line transformer). Due to uncertainties of solar irradiance generation, the power outputs of photovoltaic panels are not guaranteed which is the incentive to implement a storage system to certify adequate power supply to the DC fast charging station. Furthermore, the results are shown for a real 24-hour profile of solar irradiance and EV load. The performance of the system is evaluated in MATLAB/Simulink.