Prof. Mazumder delivered Keynote Lecture on EV Charger at the 2021 IEEE International Conference on DC Microgrid

EV Battery Supercharger: Confluence of Advanced Power Electronics and Next Generation SiC Devices

Electric vehicles (EVs) are one of the major technological advancements that help in
reducing the dependence on the fossil-fuel-based energy sources. EVs are typically charged
using Level-1 chargers, which are slow and need to be plugged in overnight. Level-1 chargers
operate using 120 V (RMS) single-phase AC available at homes. Level-2 chargers need 240 V
(RMS) single-phase input and offer relatively faster charging capabilities but still take relatively
long time to charge the batteries. A long battery charging time limit the operating range of EV and
serving time. Recently, the focus has been on DC Level-3 quick charger (DCQC), which typically
operates using 480/679 (RMS/peak) V three-phase AC input. Power levels are normally up to
about 60 kW. This results in rapid charging of the EV batteries. Typical time taken to charge to
80% is just 15-30 minutes. However, the current silicon-based power-electronic charger solutions,
which are typically transformer and multiple-conversion-stage based, are relatively low on power
density, specific power, peak efficiency, and thermal sustenance. Rapid technological
advancements, using integration of SiC technologies and novel EV charger circuit innovations
that reduce architectural and operational complexities, are needed for reduced volume, reduced
weight, lower cost, enhanced reliability, and wide (and hence universal) voltage applicability
thereby yielding greater market penetration and accelerated deployment of EV charging
infrastructure aside from providing a pathway to on-board vehicular integration of the charger at
higher power. This keynote will provide a broad outline on the newly-emerging DC battery
supercharger and how it benefits by the confluence of advanced power electronics and SiC
devices.