Partially isolated three-port converter for electric vehicle charging applications

This proposal investigates an energy management control strategy for a single stage off-board electric vehicle charger. The charger topology is a three-port dc-dc-dc converter (TPC) of the partially isolated type. This converter links two dc sources at different voltage levels with common ground and an isolated output EV battery dc port. The TPC is primarily derived from the integration of an interleaved boost with the series resonant dual active bridge (DAB) topology. The phase shift combined with pulse width modulation (PSM+ PWM) technique is utilized to achieve flexible power management strategy among three ports. Operating principles of the converter are discussed with the aid of steady state waveforms. A PSCAD-based simulation program is used for assessing the dynamics of this control system and verifying its effectiveness for photovoltaic (PV) powered off-board electric vehicle charger applications.