A high step‐up interleaved boost‐Cuk converter with integrated magnetic coupled inductors

Abstract

This paper proposes a high step-up interleaved boost-Cuk converter with integrated magnetic coupled inductor that is suitable for photovoltaic systems. By connecting the boost converter and the Cuk converter in parallel at the input terminal and the output terminal in series and integrating a coupled inductor voltage multiplier cell, the proposed converter achieves a higher voltage gain while retaining the continuous input and output current characteristics of the Cuk converter. The passive clamping branch is used to absorb the leakage inductance energy, which effectively suppresses the voltage spike generated by the switch parasitic capacitance and leakage inductance resonance and reduces the maximum voltage stress of the switch. The operation principle of the converter is analysed and the magnetic integration equivalent model and design criteria of the two coupled inductors are given. An array magnetic integrated structure is designed, which effectively reduces the DC bias inside the magnetic core. Finally, a 380 W experimental prototype is built to verify the theoretical analysis.