Investigation of Pulsed Thermoelectric Performance by Impedance Spectroscopy
Investigation of Pulsed Thermoelectric Performance by Impedance Spectroscopy
复制标题
阻抗谱研究脉冲热电性能
DOI：
10.1007/s11664-018-06922-9
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发表时间：
2019
影响因子：
2.1
通讯作者：
A. Miozzo
中科院分区：
文献类型：
--
作者：
S. Boldrini;A. Ferrario;A. Miozzo
热电技术的广泛应用通常与其有限的效率相冲突。努力克服这一限制面临的困难，从电导率去耦的热导率（由于Wiedeman-Franz定律），并同时获得高值的电导率和塞贝克系数（由于Pisarenko关系）。一些努力，以规避部分这些限制已面向非平衡的解决方案。这些已经被证明用于冷却，并且在过去的十年中已经被提出作为从随时间变化的热梯度增加功率转换的手段。已经探索的另一种可能性是通过周期性地调制施加到热电发电机的电子负载来获得热转换效率的提高。利用阻抗谱和脉冲负载施加到热电模块在绝热和非绝热测试条件下，我们探讨了几个实验参数的输出功率和转换效率的作用。我们讨论了热电脉冲负载应用的操作限制和现实前景。此外，我们研究了空气和真空阻抗测量的热电模块的品质因数的确定之间的差异，并讨论了可能使用的阻抗谱作为一种工具，通过在操作条件下的直接测量的接触热阻的研究。
A widespread use of thermoelectric technology usually collides with their limited efficiency. Efforts to overcome this limitation face difficulties in decoupling the thermal conductivity from the electrical conductivity (because of the Wiedeman–Franz law) and to obtain simultaneously high values of electrical conductivity and Seebeck coefficient (because of the Pisarenko relation). Some efforts to circumvent partially these limitations have been oriented to non-equilibrium solutions. These have been proved for cooling and in the last decade have been proposed as a means to increase power conversion from time varying thermal gradients. Another possibility that has been explored is the enhancement of thermal conversion efficiency obtained by periodically modulating the electronic load applied to a thermoelectric generator. Using impedance spectroscopy and pulsed loads applied to thermoelectric modules under adiabatic and non-adiabatic test conditions, we explored the role of several experimental parameters on the output power and conversion efficiency. We discuss operating limits and realistic perspectives of thermoelectric pulsed load application. Moreover, we examined the difference between air and vacuum impedance measurement for a thermoelectric module figure of merit determination and discussed the possible use of impedance spectroscopy as a tool for the study of thermal contact resistance by means of direct measurements under operating conditions.