Low Input Ripple High Step-Up Extendable Hybrid DC-DC Converter

The widely utilization of renewable energy with low output voltage makes the high voltage ratio boosting converter more popular. This article introduces a non-isolated low input ripple high step-up extendable hybrid DC-DC converter. The proposed converter is based on a two-phase interleaved BOOST converter and switch-capacitor (SC) boost circuit. One of the BOOST channels charges the capacitors in the SC circuit, and the other BOOST channel is connected in series with the capacitors to supply power to the load. Benefiting from this structure, the converter achieves high voltage gain, reduced semiconductor voltage stress, and low input current ripple. Moreover, the converter can be extended by increasing the number of switch-capacitor boost units or the parallel BOOST channels to perform better in voltage gain, input current ripple, and power density. The principle of operation, theoretical analysis, expansion scheme, and comparison with similar topologies are introduced in detail. Finally, a 100W prototype is implemented to verify the validity of the theoretical analysis.