A new technique for parallel connection of commutation cells: Analysis, design, and experimentation

A new technique useful for parallel connection of commutation cells is introduced in this paper. It consists of using small inductances in order to ensure dynamic and static share of the commutated current among the different switches. Operation principle, theoretical analysis, and design procedure are presented. Experimental results, obtained from a 400-W buck prototype using two commutation cells, have been used to validate the theoretical analysis and demonstrate the effectiveness of the proposed technique. Several experiments have been also accomplished to clear up the advantages of this new technique in comparison to the conventional one. Results from a three-cell buck dc-dc converter delivering 4.5 kW are also presented, revealing a balanced current sharing among cells and an excellent dynamic behavior, as foreseen in the theoretical analysis.