A Buck-Boost Photovoltaic Energy Harvester Employing Adaptive Power-Scalable MPPT Control Achieving >98% MPPT Efficiency and >82% Power Conversion Efficiency Across a 100,000× Dynamic Range

Abstract

This paper presents a photovoltaic energy harvesting (PVEH) system achieving both high Maximum Power Point Tracking (MPPT) efficiency ($\eta_{\text {MPPT }}$) and power conversion efficiency ($\left.\eta_{\text {CONV }}\right)$ across a wide input power dynamic range (DR), employing a direct input power-to-digital converter (PDC) and an adaptive power-scalable MPPT scheme. The proposed PVEH achieves $>98 \%$ (with a peak of 99.9 %) $\eta_{\text {MPPT }}$ across a $100,000 \times$ DR $(10 \mu ~\mathrm{W}$ to 1 W), representing a $10 \times$ improvement over the state-of-the-art, as well as a competitive $\eta_{\text{CONV}}$ of $>82 \%$ (with a peak of $\mathbf{9 2 \%}$) across the same DR.