Hierarchical Control of DC Coupled Fast EV Charging Station

This paper proposes a new hierarchal control scheme for DC-coupled fast electric vehicle charging stations. This control scheme coordinates the charging activities of the linked electric vehicles (EVs) with renewable energy sources and external storage solutions. The proposed solution allows bidirectional power flow and provides various ancillary services to the grid. These services include low-voltage ride through (LVRT), high-voltage ride through (HVRT), low-frequency ride through (LFRT), high-frequency ride through (HFRT), and voltage support (VS). To prove this concept, the paper will focus on LVRT and VS services. In addition to the aforementioned objectives, the proposed scheme aims to minimize the power consumed from the AC grid and take the advantage of the available renewable energy, and harvest the maximum possible power from the available renewable resources. Experimental investigations are conducted to validate the proposed concept and prove its unique advantages.