A novel common-ground phase-scalable qz-source-based interleaved DC–DC converter

High-gain non-isolated DC–DC converters play a crucial role in renewable energy systems. However, many existing converter topologies suffer from practical limitations such as poor modularity, the absence of a common ground, and high input current ripple, which restrict their applicability in real-world systems. In this study, a novel phase-scalable, interleaved high-gain DC–DC converter inspired by the quasi-Z-source (qZs) structure is proposed. In the proposed topology, qZs cells are connected in parallel at the input and in series at the output, enabling a common ground configuration while achieving high voltage gain with reduced voltage and current stresses on the power components. The proposed converter is analytically modeled, and its small-signal dynamics and control design are investigated in detail. A two-phase laboratory prototype rated at 200 W is designed and implemented to validate the theoretical analysis. Experimental results demonstrate that the converter operates stably over a wide input voltage range of 30–40 V and efficiently regulates the output voltage at 200 V. Moreover, a significant reduction in input current ripple and component stress is experimentally verified. Owing to its high voltage gain, low input current ripple, and inherent phase scalability, the proposed converter offers an effective and practical solution for modern renewable energy and distributed power conversion applications.