An Extensive Unified Thermo-Electric Module Characterization Method

Abstract

Thermo-Electric Modules (TEMs) are being increasingly used in power generation as a valid alternative to batteries, providing autonomy to sensor nodes or entire Wireless Sensor Networks, especially for energy harvesting applications. Often, manufacturers provide some essential parameters under determined conditions, like for example, maximum temperature difference between the surfaces of the TEM or for maximum heat absorption, but in many cases, a TEM-based system is operated under the best conditions only for a fraction of the time, thus, when dynamic working conditions occur, the performance estimation of TEMs is crucial to determine their actual efficiency. The focus of this work is on using a novel procedure to estimate the parameters of both the electrical and thermal equivalent model and investigate their relationship with the operating temperature and the temperature gradient. The novelty of the method consists in the use of a simple test configuration to stimulate the modules and simultaneously acquire electrical and thermal data to obtain all parameters in a single test. Two different current profiles are proposed as possible stimuli, which use depends on the available test instrumentation, and relative performance are compared both quantitatively and qualitatively, in terms of standard deviation and estimation uncertainty. Obtained results, besides agreeing with both technical literature and a further estimation method based on module specifications, also provides the designer a detailed description of the module behavior, useful to simulate its performance in different scenarios.

Comprehensive Review of Methods and Instruments for Photovoltaic–Thermoelectric Generator Hybrid System Characterization

“…Based on the same idea, Carducci et al [99] improved the unified method for TEM characterization through developing a novel measurement system, by replacing the temperature measurements using thermocouples with thermistors and their calibration, and also by reducing the number of used components. They showed, by comparing the results obtained through this new method with the ones based on thermocouples described in [100], that the uncertainty in the determination of the temperature-dependent parameters of the TEM decreased significantly. Thus, the uncertainty was reduced from 1.4 to 0.027 • C for temperature difference measurements.…”

Thermal Energy Harvesting on the Bodily Surfaces of Arms and Legs through a Wearable Thermo-Electric Generator

“…The ΔT value determines the magnitude of the TEG voltage (V TEG ) and the direction of the heat flow determines the voltage polarity. Furthermore, a ΔT change, across the TEG sides, causes a variation of the resistance value, R TEG [ 35 , 36 , 37 ]. Thus, in the application field of human heat energy harvesting, it is difficult obtain a stable value for R TEG , since the temperature across the two sides of TEG changes over time, as the result of modifications of the physiological state of the body, and from the external unpredictable environmental conditions.…”

Energy Neutral Wireless Bolt for Safety Critical Fastening

“…In terms of characterization of TEGs to find the maximum power, Gao et al [ 14 ] proposed an additional numerical analysis to improve the estimation of maximum power by measuring the open circuit voltage and short circuit current, in addition to the traditional approach as presented for example in [ 15 ]. A non-invasive thermal resistance estimation of TEGs is also presented in [ 16 , 17 ]. In a different approach [ 18 ], presents a model to predict the harvested energy using TEGs and photovoltaics based on parameters such as light intensity, temperature gradient, human activity.…”