ICT2014 Abstracts

A thermocouple monomer is the minimum unit converting heat to electric, and a series connected thermocouple module is a minimum thermoelectric cell. When building a powerful thermoelectric system, the output characteristic of thermocouple array is one of the most important performances, and its output must not only meet maximum power and matching voltage, but also have enough electric source capacity and high conversion efficiency.

This paper analyses the electric circuit of thermocouples, presented the experiment results of volt-ampere characteristic from a series of thermocouple which made of BiTe and have different sizes. Then, some output characteristics of monomer unit can be analyzed, such as changing trend of the open voltage, short-circuit current, internal resistance, load resistance, stabilization and maximum output power. According these test parameters, an equivalent circuit model of thermocouple array can be made; in addition, a circuit optimal model is made too, its maximum objective function is ‘fill factor’. By numerical calculating, the optimal output characteristics of that array can be achieved. Study shows: because that series connection resistance, over half output power is consumed from thermocouple array; the high resistance is one of the most serious influencing factors affected to raise the efficiency. And that circuit optimization of thermocouple array can improve this problem.