DC Railway Micro Grid Adopting Renewable Energy and EV Fast Charging Station

Abstract

Green and low emission transportation have been given global attention to lessen the environmental issues caused by fossil fuels and greenhouse gases. In this study, a novel system is proposed in which a large-scale hybrid renewable energy source (RESs) and electric vehicle (EV) fast-charging station are integrated into medium voltage (MV) DC electric railway power system (ERPS). Worth mentioning that the overhead catenary system is used to transfer the electrical energy from RESs (and main grid if necessary) to the EV charging station. Also, a storage system is tied to the system because of the intermittent nature of wind and solar irradiance to avoid any blackout and decrease the burden on utility grid during peaking hours. In this system, photovoltaic (PV) arrays and storage system are connected to the railway catenary system through a unidirectional DC/DC power converter to boost the voltage to 1.5 kV DC. Furthermore, the DC/DC converter provides galvanic isolation between the storage and utility grids for safety concerns. In this scrutiny, a 24-hour profile of wind speed, solar irradiance, temperature, and loads is employed to provide us with realistic outputs. The performance of such a system is evaluated in MATLAB/Simulink.