Single-Phase Single-Stage PFC Based on a Novel Floating Capacitor Filter for Electric Vehicle On-Board Charger Application

In this paper, a novel modified single-stage Dual-Active-Bridge (DAB) AC-DC converter with an active filter for Electric Vehicle (EV) On-Board Charger (OBC) application is presented. The novel topology dispenses with the DC bus thanks to an active filter connected in series with the primary side of the transformer that eliminates the natural 100 Hz power fluctuation of single-phase Power Factor Correctors (PFC-s). In this way, only the mean power is transferred to the secondary side, thus being possible to remove the storage capacitor that creates the DC bus, which is usually a bulky component with low reliability. Besides, a PFC control is described in detail, which is based on a duty-cycle regulation, integrating different functionalities, i.e., PFC, current shaping and power control on a single control strategy. Finally, these theoretical results are validated using a Gallium Nitride (GaN)-based experimental prototype.