A 78.3% Efficient Power Management System Using FOCV-Based MPPT for Thermoelectric-Powered IoT Applications

This paper presents an efficient power management system (PMS) that uses thermoelectric energy generators (TEGs) as the power source for internet of things (IoT) applications. The PMS consists of a dynamically configured controller circuit ($\mathrm{DC}^{3}$), a startup circuit (SC), and a maximum power point (MPPT) controller. The DC<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> utilizes six TEGs and a controller circuit to optimize the power from the TEGs, whether configured in series or parallel. The SC uses a transformer-based RLC oscillator and can start the overall system at the source voltage $V_{S}$ of 350 mV. The MPPT controller is based on a fractional open circuit voltage (FOCV) technique, and test results demonstrate that the tracking efficiency ($\eta_{\text {MPPT }}$) exceeds $\mathbf{9 0 \%}$ for $V_{S}=\mathbf{1 0 0} \mathbf{~ m V}$. The PMS achieves a conversion efficiency ($\eta_{\text {Conv. }}$) of $\mathbf{7 8 . 3 \%}$ for $V_{S}=100 \mathrm{mV}$, indicating the successful operation of the proposed PMS.