Minimum Conduction Loss ZVS Control for Buck-Type Active Filter Operating as Decoupling Circuit

It is becoming a useful and favorable trend to remove unreliable E-caps from the single-phase AC-DC converters which are being widely used in renewable energy applications and energy storage systems, without letting the low frequency power penetrating into the DC-side. Active filter is an attractive solution for this. Since active filter processes a major part of power, its performance affects the performance of the converter. Therefore, it is important that it operates efficiently for a wide range of operation. A minimum conduction loss ZVS control is proposed for buck-type active filter, which can be used across the DC-link of two-stage converters or across the DC side of the single-stage AC-DC converters. The control minimize the conduction losses for the buck active filter as well as obtaining ZVS for all the switching instants. Loss comparison with hard-switched control and other ZVS control methods are presented and show the effectiveness of the proposed method. Simulation and experimental results are presented.