An Extendable Interleaved Quasi Z-Source High Step-Up DC–DC Converter
Arash Nafari, Reza Beiranvand
Abstract
A quasi z-source high step-up dc–dc converter is proposed here by integrating a coupled-inductor and a quadruple voltage rectifier technique. This converter can be used for high-voltage gain applications, without using extreme duty cycle and transformer high turns ratio values. Furthermore, low-voltage rating <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> s, which have small <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> -resistances, can be used to reduce conduction losses and improve the converter efficiency. Also, single-core coupled inductors with multiwindings are used to reduce the magnetic components count. Using the interleaved technique at the converter input stage reduces the current stresses of the power <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mosfet</small> s as well as the current stresses of the primary side windings of the coupled inductor. For high power applications, number of the input stage interleaved legs can be properly chosen to reduce the input current and output voltage ripples values, which reduce the input and output filters volumes. Leakage inductances energy recovery is another benefit of the given converter. To confirm performance of the proposed converter and its operating principles, as well as the given simulation results and mathematical analyses, a two-leg topology of the introduced converter has been implemented and tested by applying both interleaved and noninterleaved gate-drive signals at different conditions.