Modelling and Analysis of Energy Harvesting in Internet of Things (IoT): Characterization of a Thermal Energy Harvesting Circuit for IoT based Applications with LTC3108

Syeda Adila Afghan,Husi Géza

doi:10.3390/en12203873

Abstract

This paper presents a simulation-based study for characterizing and analyzing the performance of a commercially available thermoelectric cooler (TEC) as a generator for harvesting heat energy along with a commercial-off-the-shelf (COTS) power management integrated circuit (PMIC); LTC3108. In this model, the transformation of heat was considered in terms of an electrical circuit simulation perspective, where temperature experienced by TEC on both cold and hot sides was incorporated with voltage supply as Vth and Vtc in the circuit. When it comes to modeling a system in a simulation program with an integrated circuit emphasis (SPICE) like environment, the selection of thermoelectric generator (TEG) and extraction methods are not straightforward as well as the lack of information from manufacturer’s datasheets can limit the grip over the analysis parameters of the module. Therefore, it is mandatory to create a prototype before implementing it over a physical system for energy harvesting circuit (EHC) optimization. The major goal was to establish the basis for devising the thermal energy scavenging based Internet of Things (IoT) system with two configurations of voltage settings for the same TEG model. This study measured the data in terms of current, voltage, series of resistive loads and various temperature gradients for generating the required power. These generated power levels from EHC prototype were able to sustain the available IoT component’s power requirement, hence it could be considered for the implementation of IoT based applications.

Highlights

Autonomous devices have expanded the way we connect, exchange, communicate and operate around the globe, from smartwatches to medical implant devices, from self-directed car parking to industrial smart machines, all of these comes under one revolutionary term i.e., Internet of Things (IoT) [1,2]
According to the available reported solutions, mostly TEC1-12706 has presented their results based on suitability and efficiency whereas, TEG2-126LDT which is prepared for lower temperature difference, proved to be an efficient solution for wearable devices. It depends on the end user when designing any thermal energy harvesting circuit (EHC) while considering the prerequisite of the application, selection of appropriate transducer, power management solutions and voltage ratings of the specific device. The goal of this simulation study was the experimental characterization of the performance of a commercially available thermoelectric cooler used as a generator for validating the usage in harvesting human body heat for wearable IoT applications
Two different setups were developed, and controlled measurements were carried out at different load configurations and varying temperature gradients. This enabled the study of the behavior and performance of complete thermoelectric generator (TEG)-based thermal

Summary

Introduction

Autonomous devices have expanded the way we connect, exchange, communicate and operate around the globe, from smartwatches to medical implant devices, from self-directed car parking to industrial smart machines, all of these comes under one revolutionary term i.e., Internet of Things (IoT) [1,2]. Despite battery support and various power management techniques that have been applied to reduce power consumption, this pervasive technology still faces the dead end. From this and energy crises due to limited fossil fuels [4] have emphasized the need to make a way out for alternative and green energy solutions.

Methods

Results

Conclusion