Analysis and simulation of ZCS current-fed full bridge high gain DC-DC converter with Synchronous rectification

This paper presents steady-state analysis and simulation of full bridge current fed dc-dc converter with Synchronous rectification. This converter is best suited for Grid connected Fuel Cell applications. Synchronous rectifier circuit with voltage doubler was implemented on the secondary side of H/F isolation Transformer. Secondary modulation technique helps in reducing blocking voltage spike of the primary side switches at low value. The proposed converter topology ensures Zero Current Switching (ZCS) on primary side and Zero Voltage Switching (ZVS) on secondary side of H/F isolation transformer. Primary devices clamped at low voltage, which intends to use power MOSFET´s with low ON-state resistance values we can go with less conduction losses moreover all power switches ensuring soft switching which will reduce the switching losses there by the converter efficiency will improve. The proposed converter is analyzed and simulated for 250W with an input voltage of 12V and the output voltage is modulated using duty cycle from 150V-300V.