Modeling And Optimization Of Solar Thermoeletric Devices For Land And Space Applications

Solar thermoelectric devices generate electric power based on Seebeck effect of semiconductor materials.Solar thermoelectric devices owe a lot of advantages,such as small size,light weight,noiseless,safe and long service life,which are ideal energy conversion devices.A method of obtaining large temperature difference is plate heat collection method,which owes simple structure and is more suitable for the space application with high radiation intensity.Another method to obtain large temperature difference is focusing the sun light by lens,which can increase the radiation intensity of the solar radiation exponentially on the ground,so that obtain a larger temperature difference between the ends of the heat unit.Firstly,the thermal analysis model of flat collector solar thermal device with Bi₂Te₃ and PbTe is constructed,and the temperature distribution of the device in AM1.5 radiation condition environment and the space environment is analyzed respectively.Based on the Seebeck effect,the effects of factors such as heat collection ratio,hot arm cross-sectional area and boom length on the open-circuit voltage,output power and conversion efficiency of the device are calculated with the temperature dependent physical parameters.Then,the thermal analysis model of concentrator solar collector based on GeSi is constructed,and the temperature distribution of the device in the AM1.5 radiation environment is obtained.The effects of factors such as collector ratio,heat unit length and thermal resistance on the output power and conversion efficiency of the device are calculated with the temperature dependent physical parameters.Finally,the main research contents and results are as follows: the conversion efficiency of flat type solar thermoelectric device based on Bi₂Te₃ material is 1.55% on the ground.The maximum conversion efficiency of Bi₂Te₃ solar thermoelectric devices operating on geosynchronous orbit is 5.5%,while the maximum conversion efficiency of PbTe solar thermoelectric devices on Venus and Mercury orbit is 4.75% and 5.84%,respectively.The maximum conversion efficiency of GeSi solar thermoelectric devices operating on the ground is 5.5%.