Design of lab-scale prototype hardware. Credit: SPELL Lab
A new fast-charging solution could boost India’s electric vehicle (EV) revolution by slashing infrastructure costs and making charging stations more sustainable1.
To supply megawatt-scale charging capacity, stations tap into the medium-voltage grid, depending on bulky, inefficient transformers and complex battery banks, driving up costs, space demand, and grid strain.
Researchers at the Indian Institute of Science (IISc), Bengaluru, in collaboration with Delta Electronics India, developed a new cascaded H-bridge (CHB)-based multiport DC converter that powers fast charging at multiple ports by plugging directly into the medium-voltage grid.
The new converter directly transforms medium-voltage AC power into low-voltage DC outputs ready for EV charging using an intermodule transformer that facilitates power sharing between charging ports without battery storage.
To demonstrate their technology, the researchers first designed a theoretical 400 kW charging station, then applied the knowledge to build a 1.2 kW laboratory prototype. The scaled-down version achieved an efficiency of over 95% in testing.
“At a megawatt scale, this leads to energy saving, significant reductions in cost, and a smaller material footprint, which makes the charging stations environmentally friendly,” said Kaushik Basu, at IISC.
The technology can enable intelligent charging hubs that can store excess energy locally and connect with solar panels. During emergencies, this could support stations in reversing power flow to infrastructure such as hospitals.
