High efficiency bidirectional 5kW DC-DC converter with super-junction MOSFETs for electric vehicle super-capacitor systems

摘要

This paper presents a high efficiency 5-kW bidirectional DC-DC converter for use in electric vehicle super-capacitor systems. Super-junction MOSFETs are deployed in the power stage to minimize losses. This is achieved using a snubber inductor and by arranging the gate signal underlap delays in order to control charging current caused by the devices' highly non-linear output capacitance and to deactivate the intrinsic body drain diode respectively. The result is a 5-kW power converter with an estimated efficiency exceeding 99% in the power semiconductor stage and requiring no forced cooling.