Soft-Switching High Static Gain Modified SEPIC Converter

The modified SEPIC converter is a high performance dc-dc converter with intrinsic high static gain and reduced voltage stress in all semiconductors used in several applications as renewable energy sources, high power factor rectifiers, LED drivers, battery chargers, and high conversion ratio bidirectional dc-dc converters. However, most part of developments proposed using this topology is based on the hard-switching structure. The reduction in converter losses and electromagnetic interference using a soft-switching technique is important for high power density applications. A simple soft-switching structure is proposed in this article suitable for the different configurations of the modified SEPIC converter, reducing the switching losses and the diodes reverse recovery current. The theoretical analysis, design procedure, and experimental results of a 180-W prototype, with 97% efficiency at nominal output power using the proposed technique, are presented in this article.