Analysis and comparison of multiphase DC/DC converters with coupled inductors in medium power applications

This paper deals with the use of coupled inductors for the DC|DC converters. A complete analysis of this topology is carried out and its advantages are demonstrated by comparing it to the DC/DC converter with uncoupled inductor. In this paper, we show how the coupled inductors allow the I²R losses reduction and the minimization of the phase and the output current ripples. Different architectures and designs of coupled inductors are given. The benefits and the drawbacks of each one are analyzed basing on three criteria: minimization of the harmonic currents, ability to filter the differential currents and the converter volume-weight. Then, simulation results of a medium power DC drive using a coupled inductor converter are given and discussed emphasizing the theoretical results and showing the advantages of the studied topology for this power range.