Active Power Decoupling Method for Single-Phase Current-Source Rectifier With No Additional Active Switches

This paper proposes an active power decoupling method without adding additional active switches for single-phase current source rectifiers. Two identical decoupling capacitors connected across the two bridge arms operate alternatively to buffer the ripple power at twice the line frequency. First the operational principle of the proposed circuit is presented. Thereafter, a hybrid modulation method, in which input current synthesis and ripple power buffering can be carried out simultaneously, is developed. Moreover, a new effective closed-control strategy is presented, in which the decoupling control is responsive for regulating dc-link current and the rectification control is in charge of power factor correction as well as maintaining the dc component of the decoupling capacitor voltages at a given level. Consequently, complete ripple power decoupling is achieved and sine input current is obtained. Finally, the theoretical analysis is favorably verified by the simulations and experimental results.