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This article presents a high‐gain DC–DC converter consisting of a quadratic boost converter and a voltage multiplier, which helps to lift up the voltage gain. The gain will be further enhanced by increasing the turn's ratio of the coupled inductor. The key features include ultrahigh gain, low voltage stress across switching devices, low input current ripple, and hence, it is preferably suitable for renewable energy applications. A passive clamp lowers the voltage stress across MOSFET, so allowing switch with lower Rds(on) reduces the system cost. Besides this, input inductor makes current continuous and reduces input current ripple. The reverse recovery problem of diodes also gets diminished with the usage of leakage energy of the coupled inductor. The operating principle with different modes of operation is also explained. Zero current switching (ZCS) turn‐on is achieved for power switch, and ZCS turn‐off is achieved for diodes, which helps to reduce the switching losses. This improves the overall system efficiency. A 250‐W prototype is built up to validate the converter. [ABSTRACT FROM AUTHOR]

A new isolated current-fed zero-current switched (ZCS) front-end dc/dc converter based multilevel inverter is proposed for multi-input applications. The proposed front-end converter with only two controllable switches integrates two different renewable energy sources, resulting in an advantageous compact structure and low conduction losses. The ZCS turn-off is achieved in both the controllable switches with the proposed modulation scheme. The converter maintains ZCS turn-off under a wide load, as well as input voltage variations by employing frequency modulation along with a variable duty ratio technique. Simple structure, soft switching, high gain, and automatic load regulation make the converter structure novel for simultaneous power management in multi-input renewable energy applications. Converter operation and design guidelines have been outlined. A laboratory prototype of the proposed converter is developed and tested at 300-W power level. Simulations and experimental results demonstrate the robust performance of the converter under load, as well as input source voltage variations. [ABSTRACT FROM PUBLISHER]