A novel approach to active DC-Link capacitance reduction for single phase power factor correction circuits

An alternative approach to DC link capacitance reduction and ripple suppression of single phase power factor correction circuits is presented. While the hardware part of the solution, consisting of a DC-DC converter transferring the oscillating power component to a reduced auxiliary capacitance is similar to other active solutions proposed in the literature by far, the operation principle is entirely different. Instead of regulating the DC link current, the proposed system gains control over the ripple by replacing the grid-interfacing converter in the task of regulating the DC link voltage. This allows increasing the voltage control bandwidth (thus reducing the ripple) without sacrificing the input power factor. The proposed method is applied to a 360W single-phase commercial PFC front end and is fully supported by experimental results.