A Semiquadratic Trans-Inverse High Step-Up DC–DC Converter for Renewable Energy Applications
Tohid Nouri, Sara Hasanpour, Sze Sing Lee
Abstract
A new high step-up dc–dc converter that is suitable for renewable energy systems is proposed in this article. By integrating a three-winding coupled-inductor (CI), a semiquadratic configuration is established for considerably enhancing voltage gain by the CI turns’ ratios, in addition to the converter duty cycle. Furthermore, a passive clamp circuit is integrated to recycle the leakage energy and prevent high spikes across the switch. This topology can be implemented using low-voltage <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small>s, which reduces losses. Furthermore, zero current switching is achieved for the power switch and input diodes, which substantially reduces the switching losses and reverse recovery problems. Low input current ripple is another benefit that is an essential characteristic for photovoltaic and fuel cell systems to extend their life span and to improve maximum power point tracking characteristics. The proposed topology is analyzed and thoroughly compared with the latest counterparts. To verify the performance of the proposed converter, a 200 W 25–400 V prototype is provided. The voltage stress of the power <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> of the sample prototype of the suggested converter is 120 V, which is about 30% of the high output voltage. Moreover, at the full-load condition, the input current ripple is 1.6 A and the measured full-load efficiency is 94.9%.