A modified SEPIC converter with high static gain for renewable applications

A high step-up DC-DC converter based on the modified SEPIC converter is presented in this paper. The proposed topology presents low switch voltage and high efficiency for low input voltage and high output voltage applications. Two alternatives with and without magnetic coupling are analyzed. The magnetic coupling allows to increase the static gain with a reduced switch voltage. The theoretical analysis and experimental results are presented. Two experimental prototypes were developed with an input voltage equal to 12 V and an output power equal to 100 W. The efficiency obtained with the prototype without magnetic coupling was equal to 91.2% with an output voltage equal to 120 V and nominal output power. Efficiency equal to 95% was obtained with the prototype with magnetic coupling operating with an output voltage equal to 240 V and nominal output power.