Abstract

This paper investigates the optimization of SEPIC-Cuk DC-DC converters to enhance efficiency and compactness, addressing the increasing demands of modern power converters. Given the topological structure, a paralleling approach is crucial due to its potential to improve both size and performance. Utilizing a bipolar SEPIC-Cuk configuration, this research meticulously evaluates, refines, and validates an experimental prototype of a bipolar DC-DC converter. To achieve optimal outcomes, the investigation employs a multi-objective metaheuristic optimization technique, focusing on efficiency and size attributes to design a cost-effective converter. The selection of design parameters - including switching frequency, capacitance, inductance, and power electronic switches - is integral to the optimization process. The proposed converter features a single switch control mechanism to operate a single input and dual output structure, ensuring high efficiency while enhancing converter response and minimizing ripple. A laboratory prototype of a low-cost 300 W converter, designed for a bipolar DC microgrid as a photovoltaic optimizer, has been developed and tested, accommodating an input voltage range of 20 V to 60 V and supporting standard output voltages. Experimental results demonstrate an average efficiency of 97.5% and 98.35% for a 300 W load, validating the effectiveness of the proposed strategy. Additionally, a comprehensive comparison between theoretical predictions and experimental findings is presented, confirming the validity and applicability of the proposed methodology.

Key words: Keywords— DC-DC converter optimization; SEPIC-Cuk converter; Efficiency analysis; Volume analysis; Inductor design; Photovoltaics.