Design of a Switched Capacitor and Inductor-Based High Gain DC-DC Converter for DC Grid-Connected Solar PV Applications

This paper proposes a novel non-isolated switched-capacitor and switched-inductor high-gain (NI-SC-SI-HG)
converter for low-voltage (LV) solar photovoltaic (PV) module-fed direct-current (DC) microgrid systems. The
primary objective is to achieve a high output voltage at a lower duty ratio using the NI-SC-SI-HG topology. The
study investigates the voltage gain, device stresses, efficiency, and component count, with a detailed comparison
to existing high-gain converters. The theoretical operation of the proposed converter is presented
comprehensively, illustrating current paths under both continuous conduction mode (CCM) and discontinuous
conduction mode (DCM). Mathematical analyses of each operating state are provided to support the design and
performance evaluation. The proposed converter facilitates the integration of LV solar systems with DC
microgrids. Additionally, its implementation in solar PV-fed applications is examined under varying irradiance
conditions. Maximum power extraction is achieved using a simple perturb-and-observe (P&O) algorithm.
MATLAB 2024a simulation waveforms are provided to illustrate the converter’s dynamic performance. To
validate the theoretical and simulation results, a 220 W, 380 V prototype of the NI-SC-SI-HG converter was
developed and tested, confirming its effectiveness and practical applicability.