Parallel hybrid converter with wide zero-volatge switching range, less switches and low circulating current losses

Abstract

This paper presents a hybrid parallel DC/DC converter to have the advantages of wider zero-voltage switching range, less primary circulating current and higher circuit efficiency. The proposed converter incudes two parallel full-bridge circuits shared the same lagging-leg switches to reduce the switch counts and current stresses of passive components on the secondary side. Half-bridge circuit is connected to the lagging-leg switches in order to extend zero-voltage switching range so that all switches have wider zero-voltage switching range. Passive snubber is used on the secondary side of full-bridge converters to reduce the circulating current at the freewheeling state so that the primary conduction losses can be reduced. Finally, the effectiveness of the proposed converter are verified by experiments with a 1.92kW prototype circuit.