A Large-capacity DC-DC Converter with Input-Series-Input-Parallel Output-Series-Output-Parallel Connection

Abstract

In order to improve the capacity of DC-DC converter, a large-capacity DC-DC converter with input-series-input-parallel output-series-output-parallel (ISIPOSOP) connection is proposed in this paper.The converter consisting of multiple basic DC-DC modules has the ability to withstand the high voltage and large current at both sides.Firstly, the paper presents the structure of ISIPOSOP DC-DC converter.Its characteristic of withstanding high voltage and large current at both sides is concluded in theory.Secondly, for fulfilling the fast stability of the output voltage of the ISIPOSOP system, an output-voltage control strategy based on an approximate small signal model is proposed.The strategy distributes the load to establish an approximate small signal model.Then the controller designed by using this model helps to realize the fast stability of output voltage.Finally, simulation of an ISIPOSOP system is given.The results verify the fast output-voltage tracking effect of the strategy.