Interleaved high step‐up ZVS DC–DC converter with coupled inductor and built‐in transformer for renewable energy systems applications

Abstract

A zero voltage switching (ZVS) interleaved high step-up converter with coupled inductor and built-in transformer voltage multiplier cell is introduced in this study. A more flexible design is provided by increasing the voltage conversion ratio by utilising the turns ratios of the coupled inductor and built-in transformer. The ZVS operation of the metal-oxide-semiconductor field-effect transistors (MOSFETs) and absorption of the leakage current are realised through active clamp circuits. Furthermore, the voltage stress across the switching devices is minimised that give rises to implementation of low voltage rated MOSFETs and consequently low conduction losses. Meanwhile, the diode reverse current problem is alleviated by the leakage inductance of the coupled inductor and built-in transformer. All of the abovementioned advantages make the proposed converter as a high efficiency candidate for high current and high step-up applications. Finally, a 600 W, 48–700 V voltage conversion with the conversion efficiency of 97% is fabricated to probe the merits of the proposed converter.