A modified active clamp circuit for a current fed DC/DC power converter for fuel cell applications

This paper presents a performance comparison between a conventional active clamp circuit (CACC) and a modified active clamp circuit (MACC) for a full bridge current-fed DC/DC converter (FBCFC) configuration for fuel cell applications. The modified active clamp circuit aims to reduce power losses in the switching devices by shaping the bridge currents. For comparison, efficiency tests have been performed in a prototype 1.2 kW FBCFC using both clamp circuits (CACC & MACC) while connected to a fuel cell (Nexa 1.2kW FC module). The test results show an improved efficiency for the converter equipped with the MACC.