An interleaved non-isolated high gain soft switching DC–DC converter with small input current ripple

Abstract

This article suggests a non-isolated high step-up interleaved DC–DC topology for renewable energy applications. Two three-winding coupled-inductors along with two voltage multiplier cells are used to enhance the voltage gain significantly. One interesting aspect of this new topology is that high duty cycles are not required to achieve high voltage gains; this is done by adjusting the turn ratio of the coupled inductors. Moreover, the presented interleaved converter enjoys not only having less current stress due to the interleaving structure, but also showing 16% increase in voltage gain compared to the best similar boost topologies. Additional elements are designed for the purpose of soft switching and gain increase, which have little effect on the cost, weight and size of the proposed converter. Interestingly, the voltage stresses both on the switching devices and passive elements are much less than the output voltage. Furthermore, the coupled inductor's leakage inductance energy is recovered by employing a passive clamp circuit to minimize stresses across the semiconductors; therefore, efficiency is improved. The suggested converter is analyzed in the steady state, and a 400 W experimental setup was implemented; the outcomes verify the practicality of the proposed boost converter in accordance with the analysis.