Research on Coupled Inductor Interleaved High Step-Up DC-DC Converter

This paper presents a high-voltage step-up DC-DC converter with an active flexible loop based on the Boost topology. By combining interleaved technology, magnetic integration technology, and voltage doubling capacitor technology, the voltage step-up of the converter is improved, and the duty range of the converter is extended by introducing an active flexible circuit composed of MOSFETs, diodes, and resistors. In addition, a coordinated control strategy of “open loop flexible compensation—closed loop linear compensation” is proposed, which effectively limits the starting inrush current of the converter and improves the dynamic performance. In this paper, the steady-state model of the converter in different duty ranges and the control idea of the coordinated control strategy are analyzed in detail, and a test prototype with a maximum output power of 100 W is built. In the hardware experiment, the steady state of the proposed converter working in different duty ranges and the dynamic start of the converter are tested, which proves the effectiveness of the proposed controller and control strategy.