Interleaved converter with ultra-high voltage gain for DC microgrid application

Abstract

ABSTRACT In this paper a new non-isolated converter with ultra-high voltage gain is presented. The proposed converter utilises coupled inductors, lift circuits and interleaved technique to convert low-level DC voltages to high-level DC voltages without high turn ratios or large duty cycles. Winding-cross-coupled inductors are employed to raise the voltage ratio. The voltage and current stress of semiconductors are reduced, which causes low conduction losses and improves the efficiency. The way the clamp circuit is used limits not only the spike voltages but also effect on the conversion ratio of the proposed converter and make it larger. The main features of this converter are high voltage gain, low voltage stress of semiconductors, low reverse recovery of diodes, low input current ripple, low conduction loss and high efficiency. A prototype of the proposed circuit is constructed in laboratory at 100 W converting 20 V to 450 V. The experimental results are compared with theoretical analysis which verifies them.