Parallel full-bridge converter with wide ZVS and low freewheeling current

The main objective of this paper is to present a direct current to direct current topology with high circuit efficiency. In this studied circuit, two full-bridge circuits and a half-bridge circuit connected in parallel are introduced to achieve the advantages of low switching loss, less primary current, low conduction loss and low filter size compared to the traditional parallel full-bridge converters. The circuit diagram, operation principles, steady-state analysis and experiments are provided to demonstrate the effectiveness of the studied topology. Finally, a 1.44-kW laboratory prototype is constructed to verify the validity of the theoretical analysis. Experimental results show that highest efficiency of 95.3% can be achieved.