Research On Double-Input Current-Fed Full-bridge Converter With Single Primary Winding

Renewable energy has attracted more attentions for solving the energy crisis and environmentalpollution. Most renewable energy are intermittent and random not possible at all times because theyare strongly dependent on the climates and weather. But they are mutually complementary in thesense that they can be utilized simultaneously to maintain continuous delivery of power to the load,which can be named as hybrid renewable power system. In such systems, the use of a multiple-inputdc/dc converter (MIC) leads to simpler circuit and lower cost, compared to the conventional use ofseveral single-input converters. This paper focuses on the topologies and control strategies of singleprimary winding current-fed MICs.In the past, the synthesization of MIC topologies based on the concept of pulsating source cells,including pulsating voltage source cells (PVSCs) and pulsating current source cells (PCSCs), havebeen proposed. Among that, non-isolated MICs are generated by connecting the non-isolated pulsingsources in series or parallel with the relevant output filter circuit; isolated MICs are generated byconnecting the isolated pulsing sources in series or parallel with the relevant output filter circuit.Isolated MICs which achieves electrical isolation is using the transformer with multiple primarywinding. Primary winding and the required power devices are increased with more input sources. Itwill lead to control difficulties and costs increase.This paper proposed a family of single primary winding current-fed MICs by using the non-isolatedpulsing current sources in parallel to replaces the input sources of the single-input converter.Compared with the multiple-primary winding MICs, it has a simple structure and more flexiblecontrol, and it only require a primary winding, reduce the leakage inductance. The input source ofmulti-input converter by paralleling boost pulsing current source can transfer energy to the loadsimultaneously or independently.A novel double-input current-fed full-bridge converter with single primary winding is chosen as anexample to illustrate its operating principle and characteristics of the isolated MICs, verify itsaccuracy and feasibility of theoretical analysis. An800W prototype has been built and tested in thelab. The experimental results verify the theoretical analysis.