基于直流瞬态Harman法测量热电器件优值系数原理,搭建热电器件综合性能表征实验系统,实现同时测量热电器件无量纲优值系数(ZT值)、Seebeck系数、电导率以及热导率,并通过Labview编程完成对实验系统的控制、数据采集、实时显示和处理。制作并改进具有夹层结构的热电器件,对此开展了性能测试评估。实验结果表明,室温下夹层结构热电器件ZT值小于常规Bi_2Te_3器件,但Seebeck系数比常规器件大;夹层结构器件电导率和热导率均大于常规器件值。
An integrated property characterization system of thermoelectric devices is established based on direct-current transient Harman method,by means of which dimensionless figure of merit (ZT),Seebeck coefficient,electrical and thermal conductivities are measured simultaneously.Through Labview graphic language programing,auto-control of experimental system,data acquisition,display and process are accomplished.Moreover,novel thermoelectric modules with sandwiched structures were fabricated,on which testing experiments were conducted.Experiment results reveal that,ZT value of novel modules is smaller than that of commercial Bi_2Te_3 modules,while Seebeck coefficient is unexpectedly larger.Meanwhile,both electrical and thermal conductivities are larger than traditional modules' value.