Interleaved centre clamped forward converter (ICCFC) for wide input voltage range applications

Abstract

A new interleaved centre clamped forward converter for high current applications is proposed. It is a series input and series output structure with common active clamp reset branch. In the proposed converter, both the high input voltage stress and output current stress are reduced. The converter comprises of two active clamp forward converters with one common centre clamp reset circuit and the series output comprises of a current double rectifier (CDR) with self-driven synchronous rectifier (SDSR). The capacitor divider at the input reduces the switching stress due to input voltage. The common centre clamp circuit enables the transformer core reset without any additional circuit and enables zero volt switching. The SDSR-based CDR reduces burden on the secondary side of the transformer by an additional current sharing. Extended duty cycle beyond 50% is achieved. Overall reduction in the size of magnetic components with reduced part count and high-power density is attained. Prototype for 50 W with input voltage in the range of 50-200 V, 5 V/10 A output at 100 kHz was developed. The experimental results match the theoretical investigations.