Modeling and analysis of the current source characteristics of a soft switched resonant converter

When driving constant voltage loads that call for the stabilization of the output current, rather than output voltage, the use of topologies that have an output current sourcing behavior could be advantageous. This study proposes and analyses a one-stage, zero current switched, high voltage gain current sourcing converter to drive such a load. The topology is based on the parallel resonant converter, but includes blocking diodes at the input bridge to assist the soft switching operation. The results of the theoretical analysis were used to develop large and small signal behavior models. The behavior of the proposed converter was tested experimentally on a 1.3kW prototype, which was fed from a low voltage source in the range of 20V to 32V. The circuit was controlled by dsPIC30F2020 (Microchip, USA). Good agreement was found between the theoretical predications and the experimental results.