A Comprehensive Review of Galvanically Isolated DC-DC Converters for Wide Voltage Gain Range Applications

Wide voltage gain range dc-dc converters are vital in applications like photovoltaic and energy storage systems. Over the past decade, extensive research has focused on developing efficient converter topologies capable of accommodating a wide voltage gain range, including wide input or output voltage ranges. This paper systematically categorizes these converters into two main groups based on their approach to extending the voltage gain range (≥1:3). The first group includes topology morphing control (TMC) based dc-dc converters, which dynamically modify the converter topology through reconfiguration at either the input or output side, or by adjusting transformer turns ratio or resonant tank components. The second category comprises isolated buck-boost converters (IBBC), boost half-bridge converters (BHBC), resonant converters, and multi-phase converters. These converters achieve wide voltage gain ranges through structural modifications or control strategies. Additionally, each group is divided into subgroups that highlight their operating principles, features, and limitations. The paper also discusses challenges, including efficiency optimization and control complexity, in achieving wide voltage gain ranges. This paper serves as a valuable resource for researchers and engineers developing high-performance isolated dc-dc converters for applications requiring a wide voltage gain range. The findings provide insights into current challenges and future research opportunities, thereby supporting the development of innovative and efficient converter topologies for wide voltage gain applications.