An integrated bi-directional power electronic converter with multi-level AC-DC/DC-AC converter and non-inverted buck-boost converter for PHEVs with minimal grid level disruptions

In order to increase energy independency and decrease harmful vehicle emissions, plug-in hybrid electric vehicles (PHEVs) have been suggested as viable replacements for conventional internal combustion (IC) vehicles. In the event that PHEVs do command a large market share, their interactions with the grid could either become a large asset or a large burden for the grid, depending on the interface used and how it is implemented. This paper will present a bi-directional converter that not only enables beneficial vehicle-to-grid (V2G) interactions, but also ensures that all power delivered to and from the grid has good power factor and near zero current harmonics. To accomplish this task, a multi-level bi-directional AC-DC converter is combined with an integrated bi-directional DC-DC converter. The proposed converter has four different modes of operation that allows it to supply power to or from the battery to either the grid or the high voltage bus of the PHEV. These capabilities make this topology an ideal candidate for HEV to V2G equipped PHEV conversions.