Experimental verification of one-dimensional models of thermoelectric generators.

Abstract

In thermoelectric power generation circuits, one-dimensional models are commonly applied to analyze the energy conversion mechanism and calculate the relationship between various parameters. The two main conclusions derived from the one-dimensional models are as follows: (1) The maximum output power of the loop is achieved when the load is equal to the internal resistance of the thermoelectric element. (2) The source of output power is the Peltier heat flux. Since it is generally believed that the thermoelectric conversion theory is relatively mature, the current research work mainly focuses on finding high-performance thermoelectric materials to improve the thermoelectric conversion efficiency, while the experimental verification of thermoelectric conversion theory is less. In this paper, the two main conclusions in the one-dimensional models are verified by the thermal power generation loop composed of Bi_{2}Te_{3} and copper wires. Experiments show that the criterion for the maximum output power in the first conclusion should be modified to be that the load resistance is equal to the sum of the internal resistance of the thermoelectric component in the circuit, the resistance at the junction between the component and the wire, as well as the resistance of the wire itself. Additionally, we also discussed whether the Peltier heat serves as the source of the output power. Therefore, the one-dimensional models of the existing thermoelectric power generation circuit merit reconsideration.