Single-Switch High-Step-Up DC-DC Converter Employing Coupled Inductor and Voltage Multiplier Cell

This paper introduces a high-step-up dc-dc converter to provide voltage boosting in low-voltage applications. The circuit contains only a single active switch and is based on the boost-type converter using coupled inductor and voltage multiplier cell. The proposed topology exhibits high efficiency, reduced voltage stress on the semiconductors and requires a low component count. The circuit is intended for applications with rated power in the order of a few hundreds of Watts, which corresponds to the typical level of a single photovoltaic (PV) module. A detailed mathematical description of the circuit operation is carried out, providing the means for the adequate design of the converter. The dynamic analysis is also addressed in the paper, and proper closed-loop operation is demonstrated. A 400 W prototype operating at 90 kHz, with an input voltage range of 24-48 V and output voltage of 400 V was built and tested in laboratory. Experimental results validate the analyses carried out and measurements indicate efficiency levels up to 97.5%, which ratifies the proposed converter as a good solution for typical PV applications.