A Primary Full-Integrated Active Filter Auxiliary Power Module in Electrified Vehicle Applications with Single-Phase Onboard Chargers

The active filter auxiliary power module (AFAPM) has been proposed for electrified vehicle applications with single-phase onboard chargers. It has two modes: 1) the highvoltage (HV) active filtering mode, in which the vehicle is connected to the grid and the converter assimilates the significant second-order harmonic current introduced by the single-phase power; 2) the low-voltage (LV) battery charging mode, in which the vehicle is running and the converter charges the LV battery from HV battery. This yields a significant capacitance reduction on the DC-link of HV battery charger without an additional active filter (AF) circuit. However, extra relay and inductors are needed. This paper proposes a primary full-integrated AFAPM, which is composed of a two-phase buck converter to work as an AF and a dual-active-bridge (DAB) to operate as a LV battery charger auxiliary power module (APM). With the proposed converter, only an active energy storage capacitor is needed to achieve the active filtering and store the second-order harmonic energy. All the switches and inductors on the primary stage are shared between the AF and APM. Therefore, the cost and size of the dual-voltage charging system in the vehicle applications can be reduced further. To confirm the effectiveness of the proposed converter, a 720 W prototype has been built and experimental results are presented.