Active Power Decoupling Method based on Dual Active Bridge Converter using Input Voltage Compensation

In this paper, an active power decoupling method using a Dual Active Bridge (DAB) converter is proposed for isolated single-phase AC-DC converter applications. The single-phase power ripple at twice the grid frequency increases the volume of energy buffer as the electrolytic capacitor. Moreover, the electrolytic capacitor may limit the system reliability of the single-phase converter. The active power decoupling technique is a solution to this problem. However, the additional component that provides power decoupling capability decreases power density and efficiency. This paper proposes an active power decoupling method without additional components. The validity of the proposed method is demonstrated by the experimental result. As an experimental result, it was confirmed that the second harmonic component in DC voltage was reduced by 98.5%.