A new family of isolated two-stage converter

A new family isolated two-stage converter topologies are proposed in this paper. The front-stage is uncontrolled buck-type converter without output capacitor, more like a current source. The second-stage is a couple-buck converter. The whole converter size can be reduced due to removal of intermediate bus capacitor. Continuous intermediate bus current and output current can be achieved. Good stability of the cascaded two stages converter can also be achieved. A 1V/20A experimental prototype converter based on the proposed two-stage topology has been built up to verify the theoretical analysis. Experimental results meet the theoretical analysis very well.