A Modified Dual-Duty-Triple-Mode High Step-Up DC–DC Converter With Low Input Current Ripple and Common Ground

Transformerless high-gain dc–dc converters, such as dual-duty-triple-mode (DDTM) converters, are employed in various applications, including dc microgrids and renewable energy systems. The main feature of DDTM converters is their flexibility in achieving a high voltage gain through various duty cycle combinations. However, due to the utilization of an active switched inductor network, they exhibit significant input current ripple and lack a common ground. This article proposes a new quadratic-based DDTM dc–dc converter with a reduced number of switches, achieving high voltage gain and significantly reducing the voltage stress across the components. Furthermore, the proposed design achieves two notable features not found in other DDTMs, including an input–output common ground connection and low input current ripple. The operation principles, steady-state analysis, design guidelines, efficiency calculations, and small-signal modeling with controller design are described. To illustrate the superiority of the proposed converter, it is comprehensively compared with other relevant recently published converters, demonstrating that the proposed converter offers higher voltage gain, cconsiderably lower voltage stress across components, higher efficiency, and lower cost. A 500 W lab-based (20/400 V) prototype is implemented and subjected to thorough assessments, validating the theoretical analysis.