Interleaved soft-switching multilevel boost converter with coupled inductor

The dc-dc converters which are suitable for the fuel cell need high boost ability, low input current ripple, and small size. As one of the dc-dc converters having the three characteristics, interleaved soft-switching multilevel boost converter is proposed. This circuit is composed of two multilevel boost converter parts and an auxiliary inductor. By the auxiliary inductor, the switches can achieve low voltage switching. However, this circuit has a disadvantage of employing many circuit component. This paper proposes interleaved soft-switching multilevel boost converter with coupled inductor. The proposed circuit reduces the number of circuit components by coupling the two inductors in interleaved soft-switching multilevel boost converter. Additionally, since the leakage inductance takes a role as the auxiliary inductor of the conventional circuit, the proposed circuit realizes the smaller size and the lower cost. Furthermore, the proposed circuit achieves half the input current ripple of the conventional circuit. The operational principle of the proposed circuit has been confirmed by analysis and reduced scale circuit experiment in steady-state.