Input Filter Design Issues for Capacitive-link Transformer-less EV Universal Battery Supercharger

A design methodology and optimization mechanism suited for differential mode (DM) capacitive-link transformer-less electric vehicle (EV) universal battery supercharger (UBS) is outlined. The unique design challenges related to the UBS are explored, including the effect of capacitive link and DM topology and modulation in the filter design. Moreover, the inherent structure of the Ćuk topology is used to reduce the number of passive components in an LCL input DM filter for this EV charger. Design constraints are defined in the context of the presented rectifier, and an algorithm to approach it is outlined.