A novel high power density dual-buck inverter with coupled filter inductors

Abstract

The Dual Buck Inverter (DBI) does not need dead time and has no shoot-through concerns and the free-wheeling diodes can be chosen independently with fast reverse recovery features to minimize switching loss, it has great advantages in reliability and efficiency. However, since the current of filter inductors is half cycle sinusoidal wave, the utilization rate of magnetic is low. In order to overcome the shortcomings, a novel high power density dual-buck inverter with coupled filter inductors (HPDDBI) is proposed in the paper. In the proposed HPDDBIs, a inductor, works in full line cycle, is separated from the primary inductors and served as a dominant filter inductor (DFT); the two remaining DC filter inductors, work in half line cycle, are coupled together. The proposed HPDDBIs effectively decrease the volume and weight of the inverter. Furthermore, the circulating current issue in the conventional Dual Buck topology with coupled inductors can be solved. The operating principles of the proposed HPDDBIs are analyzed in detail. The design guidelines of the filter are given out. Finally, experimental results verify the theoretical analysis.