Performance Analyze And Experimental Study On Semiconductor Thermoelectric Module Which Works At Small Temperature Difference

The semiconductor thermoelectric generator is a device that can convert heat into electric power directly. It bases on the Seebeck effect. There are special advantages as a kind of energy conversion method. It is suitable for utilizing the heat which is at low temperature state specially.Exergy is analyzed during the working process of thermoelectric generator in this paper. Exergy efficiency is advanced. Exergy efficiency can be used to evaluate the performance of thermoelectric generator. The working performance of thermoelectric generator is analyzed mainly on the base of couple size, contact effect and Thomson effect. Because of the influence of the contact effect, the work efficiency of thermoelectric generator will fall with length decreasing of couple arm. The more remarkable of contact effect, the more quickly of the work efficiency will fall. The Thomson effect has influence on output power, but there are no influence on matching condition when obtain the maximize output power. The low temperature of cold junction is advantageous to reduce the influence of Thomson effect. The working model of two stages generator has been established on the base of single layer generator which works at internally and externally irreversible model, obtain the calculation formula of efficiency and output power, analyze the relation of the couple quantity between the first stage and the second stage, point that it is different from two-stage semiconductor thermoelectric cooler. From the point of entropy generation, entropy generation in thermoelectric generator is analyzed under three different conditions by entropy generation minimization method. After theory analyzing, the experiment is carried out. The test-bed is built about small temperature differential thermoelectric generator. The thermoelectric module is connected with parallel connection and in series respectively. The measure method of performance parameters is analyzed. The curves of output power vs. load resistance,work efficiency vs. load resistance and exergy efficiency vs. load resistance are obtain at different cases, and load resistance is constant, the curves of work efficiency vs.