Modeling of a Three-Input Fourth-Order Integrated DC-DC Converter

A three-input integrated dc-dc converter is designed by integrating two boost converters and a buck-boost dc-dc converter. This converter processes power from three different voltage sources Vg1, Vg2, Vg3 and regulates the dc-bus voltage along with the two LVS currents ig1 and ig2. The proposed converter incorporates four energy storing elements which makes it efficient and cost effective. The integrated dc-dc converter is modelled using state-space analysis. The state-space analysis is used to model this integrated converter that operates in four modes of operation. Its formulation is based on the average conduction periods of switches and these are denoted using duty ratios of the converter switches (which are the control inputs). The transfer function matrix (TFM) is acquired from the small signal continuous time model. The detailed mathematical modelling and TFM of the proposed converter is presented in the paper.