3X DC-DC Multiplier/Divider for HEV Systems

This paper presents a bidirectional 3X dc-dc multiplier/divider that can interface the battery with the inverter dc bus for hybrid electric vehicle (HEV) traction drives. Compared with traditional multi-level dc-dc converter, this converter can have three output/input voltage ratios with smooth transition. The control method to limit the transient inrush current, as well as a novel regenerative clamping circuit for multi-level dc-dc converters is provided in this paper. By utilizing the parasitic inductance or the minimum inductance from an air core inductor, the size and weight of the converter can be significantly reduced. Its magnetic-less feature and high efficiency provide the potential of the high temperature operation with the future wide bandgap devices. Experimental results are given to verify the operating principle and the design concepts of this topology.