A New Three-Winding Coupled Inductor Nonisolated Quasi-Z-Source High Step-Up DC–DC Converter

Abstract

This article presents a new three-winding coupled inductor high step-up quasi-Z-source dc–dc converter with single magnetic core and voltage multiplier techniques. Conventional quasi-Z-source-based dc–dc converters not only suffer limited voltage gain and high voltage stresses on semiconductors but also have utilized two or more magnetic cores in their structures. However, the suggested converter shares high voltage gain with continuous input current, low normalized voltage stresses on switch and diodes, low total voltage stresses on semiconductors, and common ground between input energy source and load. Also, this converter with single power switch and magnetic core has not limited the duty cycle. Furthermore, the proposed converter has good efficiency at high output voltage, and hence it is suitable for high voltage dc bus of three-phase inverters in renewable energy applications. The mathematical analysis, operating principle for the proposed converter, and comparison with other Z-source-based converters are provided. At last, a 400-W prototype is built in the laboratory, which has validated the accuracy of the proposed converter.