Energy harvesting has become a promising and alternative solution to conventional\nenergy generation patterns to overcome the problem of supplying autonomous electrical systems.\nMore particularly, thermal energy harvesting technologies have drawn a major interest in both\nresearch and industry. Thermoelectric Generators (TEGs) can be used in two different operating\nconditions, under constant temperature gradient or constant heat flow. The commonly used TEG\nelectrical model, based on a voltage source in series with an electrical resistance, shows its limitations\nespecially under constant heat flow conditions. Here, the analytical electrical modeling, taking into\nconsideration the internal and contact thermal resistances of a TEG under constant temperature\ngradient and constant heat flow conditions, is first given. To give further insight into the electrical\nbehavior of a TEG module in different operating conditions, we propose a new and original way\nof emulating the above analytical expressions with usual electronics components (voltage source,\nresistors, diode), whose values are determined with the TEG�s parameters. Note that such a TEG\nemulation is particularly suited when designing the electronic circuitry commonly associated to\nthe TEG, to realize both Maximum Power Point Tracking and output voltage regulation. First, the\nproposed equivalent electrical circuits are validated through simulation with a SPICE environment in\nstatic operating conditions using only one value of either temperature gradient or heat flow. Then,\nthey are also analyzed in dynamic operating conditions where both temperature gradient and heat\nflow are considered as time-varying functions.
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