Abstract
The development of Li-ion battery performance in next ten years will encourage improving a power density of Electric Vehicles (EVs). A higher voltage system with a boost voltage converter is favorable for the EV system if the converter has large power in small size. For increasing the converter power density, interleaved topologies using closecoupled inductors are shown to be superior. The inductor set of 3-phase type is proved to be smaller in size and lose less power in comparison to that of 2-phase type for high powered EV system having a 200~400 volt battery. The prototype 3- phase converter using IGBT with 15 kHz switching frequency achieved a power density of 21.4 kW/liter at 120 kW output on a boost ratio of 1.38 with 98.0% efficiency, which also achieved more than 97% efficiency in a frequent usage zone.
KEYWORDS: EV, FCV, HEV, DC/DC converter, inductor, coupled inductors, power density, flux cancelation