Design and analysis of a charge-pump-assisted high-gain DC?DC converter for low-voltage hybrid PV?TEG energy harvesting applications

Low-voltage renewable energy harvesting applications, particularly hybrid photovoltaic?thermoelectric generator (PV?TEG) systems, require high-gain DC?DC converters capable of efficiently boosting low and fluctuating input voltages while maintaining high conversion stability. However, conventional converter topologies often suffer from limited voltage gain, increased semiconductor stress, and reduced performance under the variable operating conditions characteristic of hybrid PV?TEG energy harvesting. To address these challenges, this paper proposes a novel Charge-Pump-Assisted Voltage Booster (CPAVB) converter for low-voltage hybrid PV?TEG energy harvesting applications. The proposed topology integrates inductive and capacitive energy storage elements in a charge-pump-assisted series-stacking configuration to achieve a high static voltage gain at moderate duty cycles while reducing component stress and improving conversion stability. Comprehensive simulation studies were performed in MATLAB/Simulink under diverse operating conditions, including uniform irradiance and temperature, partial shading with thermal non-uniformity, and low-voltage scenarios. The proposed converter demonstrated stable operation, rapid dynamic response, and accurate maximum power extraction. Furthermore, its applicability to a single-phase grid-connected hybrid PV?TEG system was investigated through simulation, where it maintained a well-regulated DC-link voltage, enabled unity power factor operation, achieved a simulated grid-current total harmonic distortion (THD) of 0.08%, and injected active power closely matching the theoretical hybrid maximum. To validate the proposed converter, a hardware prototype was developed and experimentally evaluated. The experimental results confirmed the predicted voltage gain, stable low-voltage operation, and acceptable semiconductor voltage stresses, demonstrating the practicality of the proposed converter. Overall, the combined simulation and converter-level experimental results demonstrate that the proposed CPAVB converter is a promising high-gain power conversion solution for low-voltage renewable energy harvesting applications and provides a practical interface for future hybrid PV?TEG systems and microgrid integration.